diff options
Diffstat (limited to 'docs/api-guide')
| -rwxr-xr-x[-rw-r--r--] | docs/api-guide/authentication.md | 307 | ||||
| -rw-r--r-- | docs/api-guide/content-negotiation.md | 35 | ||||
| -rw-r--r-- | docs/api-guide/exceptions.md | 68 | ||||
| -rw-r--r-- | docs/api-guide/fields.md | 293 | ||||
| -rw-r--r-- | docs/api-guide/filtering.md | 276 | ||||
| -rw-r--r-- | docs/api-guide/format-suffixes.md | 25 | ||||
| -rwxr-xr-x[-rw-r--r--] | docs/api-guide/generic-views.md | 319 | ||||
| -rw-r--r-- | docs/api-guide/pagination.md | 26 | ||||
| -rw-r--r-- | docs/api-guide/parsers.md | 82 | ||||
| -rw-r--r-- | docs/api-guide/permissions.md | 145 | ||||
| -rw-r--r-- | docs/api-guide/relations.md | 448 | ||||
| -rw-r--r-- | docs/api-guide/renderers.md | 199 | ||||
| -rw-r--r-- | docs/api-guide/requests.md | 6 | ||||
| -rw-r--r-- | docs/api-guide/responses.md | 15 | ||||
| -rw-r--r-- | docs/api-guide/reverse.md | 6 | ||||
| -rw-r--r-- | docs/api-guide/routers.md | 153 | ||||
| -rw-r--r-- | docs/api-guide/serializers.md | 438 | ||||
| -rw-r--r-- | docs/api-guide/settings.md | 252 | ||||
| -rw-r--r-- | docs/api-guide/status-codes.md | 7 | ||||
| -rw-r--r-- | docs/api-guide/testing.md | 272 | ||||
| -rw-r--r-- | docs/api-guide/throttling.md | 53 | ||||
| -rw-r--r-- | docs/api-guide/views.md | 26 | ||||
| -rw-r--r-- | docs/api-guide/viewsets.md | 237 |
23 files changed, 3146 insertions, 542 deletions
diff --git a/docs/api-guide/authentication.md b/docs/api-guide/authentication.md index 8ed6ef31..1a1c68b8 100644..100755 --- a/docs/api-guide/authentication.md +++ b/docs/api-guide/authentication.md @@ -8,25 +8,33 @@ Authentication is the mechanism of associating an incoming request with a set of identifying credentials, such as the user the request came from, or the token that it was signed with. The [permission] and [throttling] policies can then use those credentials to determine if the request should be permitted. -REST framework provides a number of authentication policies out of the box, and also allows you to implement custom policies. +REST framework provides a number of authentication schemes out of the box, and also allows you to implement custom schemes. -Authentication will run the first time either the `request.user` or `request.auth` properties are accessed, and determines how those properties are initialized. +Authentication is always run at the very start of the view, before the permission and throttling checks occur, and before any other code is allowed to proceed. The `request.user` property will typically be set to an instance of the `contrib.auth` package's `User` class. The `request.auth` property is used for any additional authentication information, for example, it may be used to represent an authentication token that the request was signed with. +--- + +**Note:** Don't forget that **authentication by itself won't allow or disallow an incoming request**, it simply identifies the credentials that the request was made with. + +For information on how to setup the permission polices for your API please see the [permissions documentation][permission]. + +--- + ## How authentication is determined -The authentication policy is always defined as a list of classes. REST framework will attempt to authenticate with each class in the list, and will set `request.user` and `request.auth` using the return value of the first class that successfully authenticates. +The authentication schemes are always defined as a list of classes. REST framework will attempt to authenticate with each class in the list, and will set `request.user` and `request.auth` using the return value of the first class that successfully authenticates. If no class authenticates, `request.user` will be set to an instance of `django.contrib.auth.models.AnonymousUser`, and `request.auth` will be set to `None`. The value of `request.user` and `request.auth` for unauthenticated requests can be modified using the `UNAUTHENTICATED_USER` and `UNAUTHENTICATED_TOKEN` settings. -## Setting the authentication policy +## Setting the authentication scheme -The default authentication policy may be set globally, using the `DEFAULT_AUTHENTICATION_CLASSES` setting. For example. +The default authentication schemes may be set globally, using the `DEFAULT_AUTHENTICATION` setting. For example. REST_FRAMEWORK = { 'DEFAULT_AUTHENTICATION_CLASSES': ( @@ -35,7 +43,13 @@ The default authentication policy may be set globally, using the `DEFAULT_AUTHEN ) } -You can also set the authentication policy on a per-view basis, using the `APIView` class based views. +You can also set the authentication scheme on a per-view or per-viewset basis, +using the `APIView` class based views. + + from rest_framework.authentication import SessionAuthentication, BasicAuthentication + from rest_framework.permissions import IsAuthenticated + from rest_framework.response import Response + from rest_framework.views import APIView class ExampleView(APIView): authentication_classes = (SessionAuthentication, BasicAuthentication) @@ -52,7 +66,7 @@ Or, if you're using the `@api_view` decorator with function based views. @api_view(['GET']) @authentication_classes((SessionAuthentication, BasicAuthentication)) - @permissions_classes((IsAuthenticated,)) + @permission_classes((IsAuthenticated,)) def example_view(request, format=None): content = { 'user': unicode(request.user), # `django.contrib.auth.User` instance. @@ -60,24 +74,59 @@ Or, if you're using the `@api_view` decorator with function based views. } return Response(content) +## Unauthorized and Forbidden responses + +When an unauthenticated request is denied permission there are two different error codes that may be appropriate. + +* [HTTP 401 Unauthorized][http401] +* [HTTP 403 Permission Denied][http403] + +HTTP 401 responses must always include a `WWW-Authenticate` header, that instructs the client how to authenticate. HTTP 403 responses do not include the `WWW-Authenticate` header. + +The kind of response that will be used depends on the authentication scheme. Although multiple authentication schemes may be in use, only one scheme may be used to determine the type of response. **The first authentication class set on the view is used when determining the type of response**. + +Note that when a request may successfully authenticate, but still be denied permission to perform the request, in which case a `403 Permission Denied` response will always be used, regardless of the authentication scheme. + +## Apache mod_wsgi specific configuration + +Note that if deploying to [Apache using mod_wsgi][mod_wsgi_official], the authorization header is not passed through to a WSGI application by default, as it is assumed that authentication will be handled by Apache, rather than at an application level. + +If you are deploying to Apache, and using any non-session based authentication, you will need to explicitly configure mod_wsgi to pass the required headers through to the application. This can be done by specifying the `WSGIPassAuthorization` directive in the appropriate context and setting it to `'On'`. + + # this can go in either server config, virtual host, directory or .htaccess + WSGIPassAuthorization On + +--- + # API Reference ## BasicAuthentication -This policy uses [HTTP Basic Authentication][basicauth], signed against a user's username and password. Basic authentication is generally only appropriate for testing. +This authentication scheme uses [HTTP Basic Authentication][basicauth], signed against a user's username and password. Basic authentication is generally only appropriate for testing. If successfully authenticated, `BasicAuthentication` provides the following credentials. * `request.user` will be a Django `User` instance. * `request.auth` will be `None`. -**Note:** If you use `BasicAuthentication` in production you must ensure that your API is only available over `https` only. You should also ensure that your API clients will always re-request the username and password at login, and will never store those details to persistent storage. +Unauthenticated responses that are denied permission will result in an `HTTP 401 Unauthorized` response with an appropriate WWW-Authenticate header. For example: + + WWW-Authenticate: Basic realm="api" + +**Note:** If you use `BasicAuthentication` in production you must ensure that your API is only available over `https`. You should also ensure that your API clients will always re-request the username and password at login, and will never store those details to persistent storage. ## TokenAuthentication -This policy uses a simple token-based HTTP Authentication scheme. Token authentication is appropriate for client-server setups, such as native desktop and mobile clients. +This authentication scheme uses a simple token-based HTTP Authentication scheme. Token authentication is appropriate for client-server setups, such as native desktop and mobile clients. -To use the `TokenAuthentication` policy, include `rest_framework.authtoken` in your `INSTALLED_APPS` setting. +To use the `TokenAuthentication` scheme, include `rest_framework.authtoken` in your `INSTALLED_APPS` setting: + + INSTALLED_APPS = ( + ... + 'rest_framework.authtoken' + ) + +Make sure to run `manage.py syncdb` after changing your settings. The `authtoken` database tables are managed by south (see [Schema migrations](#schema-migrations) below). You'll also need to create tokens for your users. @@ -93,17 +142,36 @@ For clients to authenticate, the token key should be included in the `Authorizat If successfully authenticated, `TokenAuthentication` provides the following credentials. * `request.user` will be a Django `User` instance. -* `request.auth` will be a `rest_framework.tokenauth.models.BasicToken` instance. +* `request.auth` will be a `rest_framework.authtoken.models.BasicToken` instance. + +Unauthenticated responses that are denied permission will result in an `HTTP 401 Unauthorized` response with an appropriate WWW-Authenticate header. For example: + + WWW-Authenticate: Token + +The `curl` command line tool may be useful for testing token authenticated APIs. For example: + + curl -X GET http://127.0.0.1:8000/api/example/ -H 'Authorization: Token 9944b09199c62bcf9418ad846dd0e4bbdfc6ee4b' + +--- + +**Note:** If you use `TokenAuthentication` in production you must ensure that your API is only available over `https`. + +--- -**Note:** If you use `TokenAuthentication` in production you must ensure that your API is only available over `https` only. +#### Generating Tokens If you want every user to have an automatically generated Token, you can simply catch the User's `post_save` signal. + from django.dispatch import receiver + from rest_framework.authtoken.models import Token + @receiver(post_save, sender=User) def create_auth_token(sender, instance=None, created=False, **kwargs): if created: Token.objects.create(user=instance) +Note that you'll want to ensure you place this code snippet in an installed `models.py` module, or some other location that will be imported by Django on startup. + If you've already created some users, you can generate tokens for all existing users like this: from django.contrib.auth.models import User @@ -112,11 +180,10 @@ If you've already created some users, you can generate tokens for all existing u for user in User.objects.all(): Token.objects.get_or_create(user=user) -When using `TokenAuthentication`, you may want to provide a mechanism for clients to obtain a token given the username and password. -REST framework provides a built-in view to provide this behavior. To use it, add the `obtain_auth_token` view to your URLconf: +When using `TokenAuthentication`, you may want to provide a mechanism for clients to obtain a token given the username and password. REST framework provides a built-in view to provide this behavior. To use it, add the `obtain_auth_token` view to your URLconf: urlpatterns += patterns('', - url(r'^api-token-auth/', 'rest_framework.authtoken.obtain_auth_token') + url(r'^api-token-auth/', 'rest_framework.authtoken.views.obtain_auth_token') ) Note that the URL part of the pattern can be whatever you want to use. @@ -125,32 +192,222 @@ The `obtain_auth_token` view will return a JSON response when valid `username` a { 'token' : '9944b09199c62bcf9418ad846dd0e4bbdfc6ee4b' } -<!-- -## OAuthAuthentication +Note that the default `obtain_auth_token` view explicitly uses JSON requests and responses, rather than using default renderer and parser classes in your settings. If you need a customized version of the `obtain_auth_token` view, you can do so by overriding the `ObtainAuthToken` view class, and using that in your url conf instead. -This policy uses the [OAuth 2.0][oauth] protocol to authenticate requests. OAuth is appropriate for server-server setups, such as when you want to allow a third-party service to access your API on a user's behalf. +#### Schema migrations -If successfully authenticated, `OAuthAuthentication` provides the following credentials. +The `rest_framework.authtoken` app includes a south migration that will create the authtoken table. -* `request.user` will be a Django `User` instance. -* `request.auth` will be a `rest_framework.models.OAuthToken` instance. ---> +If you're using a [custom user model][custom-user-model] you'll need to make sure that any initial migration that creates the user table runs before the authtoken table is created. + +You can do so by inserting a `needed_by` attribute in your user migration: + + class Migration: + + needed_by = ( + ('authtoken', '0001_initial'), + ) + + def forwards(self): + ... + +For more details, see the [south documentation on dependencies][south-dependencies]. + +Also note that if you're using a `post_save` signal to create tokens, then the first time you create the database tables, you'll need to ensure any migrations are run prior to creating any superusers. For example: + + python manage.py syncdb --noinput # Won't create a superuser just yet, due to `--noinput`. + python manage.py migrate + python manage.py createsuperuser ## SessionAuthentication -This policy uses Django's default session backend for authentication. Session authentication is appropriate for AJAX clients that are running in the same session context as your website. +This authentication scheme uses Django's default session backend for authentication. Session authentication is appropriate for AJAX clients that are running in the same session context as your website. If successfully authenticated, `SessionAuthentication` provides the following credentials. * `request.user` will be a Django `User` instance. * `request.auth` will be `None`. +Unauthenticated responses that are denied permission will result in an `HTTP 403 Forbidden` response. + +If you're using an AJAX style API with SessionAuthentication, you'll need to make sure you include a valid CSRF token for any "unsafe" HTTP method calls, such as `PUT`, `PATCH`, `POST` or `DELETE` requests. See the [Django CSRF documentation][csrf-ajax] for more details. + +## OAuthAuthentication + +This authentication uses [OAuth 1.0a][oauth-1.0a] authentication scheme. OAuth 1.0a provides signature validation which provides a reasonable level of security over plain non-HTTPS connections. However, it may also be considered more complicated than OAuth2, as it requires clients to sign their requests. + +This authentication class depends on the optional `django-oauth-plus` and `oauth2` packages. In order to make it work you must install these packages and add `oauth_provider` to your `INSTALLED_APPS`: + + INSTALLED_APPS = ( + ... + `oauth_provider`, + ) + +Don't forget to run `syncdb` once you've added the package. + + python manage.py syncdb + +#### Getting started with django-oauth-plus + +The OAuthAuthentication class only provides token verification and signature validation for requests. It doesn't provide authorization flow for your clients. You still need to implement your own views for accessing and authorizing tokens. + +The `django-oauth-plus` package provides simple foundation for classic 'three-legged' oauth flow. Please refer to [the documentation][django-oauth-plus] for more details. + +## OAuth2Authentication + +This authentication uses [OAuth 2.0][rfc6749] authentication scheme. OAuth2 is more simple to work with than OAuth1, and provides much better security than simple token authentication. It is an unauthenticated scheme, and requires you to use an HTTPS connection. + +This authentication class depends on the optional [django-oauth2-provider][django-oauth2-provider] project. In order to make it work you must install this package and add `provider` and `provider.oauth2` to your `INSTALLED_APPS`: + + INSTALLED_APPS = ( + ... + 'provider', + 'provider.oauth2', + ) + +Then add `OAuth2Authentication` to your global `DEFAULT_AUTHENTICATION` setting: + + 'DEFAULT_AUTHENTICATION_CLASSES': ( + 'rest_framework.authentication.OAuth2Authentication', + ), + +You must also include the following in your root `urls.py` module: + + url(r'^oauth2/', include('provider.oauth2.urls', namespace='oauth2')), + +Note that the `namespace='oauth2'` argument is required. + +Finally, sync your database. + + python manage.py syncdb + python manage.py migrate + +--- + +**Note:** If you use `OAuth2Authentication` in production you must ensure that your API is only available over `https`. + +--- + +#### Getting started with django-oauth2-provider + +The `OAuth2Authentication` class only provides token verification for requests. It doesn't provide authorization flow for your clients. + +The OAuth 2 authorization flow is taken care by the [django-oauth2-provider][django-oauth2-provider] dependency. A walkthrough is given here, but for more details you should refer to [the documentation][django-oauth2-provider-docs]. + +To get started: + +##### 1. Create a client + +You can create a client, either through the shell, or by using the Django admin. + +Go to the admin panel and create a new `Provider.Client` entry. It will create the `client_id` and `client_secret` properties for you. + +##### 2. Request an access token + +To request an access token, submit a `POST` request to the url `/oauth2/access_token` with the following fields: + +* `client_id` the client id you've just configured at the previous step. +* `client_secret` again configured at the previous step. +* `username` the username with which you want to log in. +* `password` well, that speaks for itself. + +You can use the command line to test that your local configuration is working: + + curl -X POST -d "client_id=YOUR_CLIENT_ID&client_secret=YOUR_CLIENT_SECRET&grant_type=password&username=YOUR_USERNAME&password=YOUR_PASSWORD" http://localhost:8000/oauth2/access_token/ + +You should get a response that looks something like this: + + {"access_token": "<your-access-token>", "scope": "read", "expires_in": 86399, "refresh_token": "<your-refresh-token>"} + +##### 3. Access the API + +The only thing needed to make the `OAuth2Authentication` class work is to insert the `access_token` you've received in the `Authorization` request header. + +The command line to test the authentication looks like: + + curl -H "Authorization: Bearer <your-access-token>" http://localhost:8000/api/ + +### Alternative OAuth 2 implementations + +Note that [Django OAuth Toolkit][django-oauth-toolkit] is an alternative external package that also includes OAuth 2.0 support for REST framework. + +--- + # Custom authentication -To implement a custom authentication policy, subclass `BaseAuthentication` and override the `.authenticate(self, request)` method. The method should return a two-tuple of `(user, auth)` if authentication succeeds, or `None` otherwise. +To implement a custom authentication scheme, subclass `BaseAuthentication` and override the `.authenticate(self, request)` method. The method should return a two-tuple of `(user, auth)` if authentication succeeds, or `None` otherwise. + +In some circumstances instead of returning `None`, you may want to raise an `AuthenticationFailed` exception from the `.authenticate()` method. + +Typically the approach you should take is: + +* If authentication is not attempted, return `None`. Any other authentication schemes also in use will still be checked. +* If authentication is attempted but fails, raise a `AuthenticationFailed` exception. An error response will be returned immediately, regardless of any permissions checks, and without checking any other authentication schemes. + +You *may* also override the `.authenticate_header(self, request)` method. If implemented, it should return a string that will be used as the value of the `WWW-Authenticate` header in a `HTTP 401 Unauthorized` response. + +If the `.authenticate_header()` method is not overridden, the authentication scheme will return `HTTP 403 Forbidden` responses when an unauthenticated request is denied access. + +## Example + +The following example will authenticate any incoming request as the user given by the username in a custom request header named 'X_USERNAME'. + + from django.contrib.auth.models import User + from rest_framework import authentication + from rest_framework import exceptions + + class ExampleAuthentication(authentication.BaseAuthentication): + def authenticate(self, request): + username = request.META.get('X_USERNAME') + if not username: + return None + + try: + user = User.objects.get(username=username) + except User.DoesNotExist: + raise exceptions.AuthenticationFailed('No such user') + + return (user, None) + +--- + +# Third party packages + +The following third party packages are also available. + +## Digest Authentication + +HTTP digest authentication is a widely implemented scheme that was intended to replace HTTP basic authentication, and which provides a simple encrypted authentication mechanism. [Juan Riaza][juanriaza] maintains the [djangorestframework-digestauth][djangorestframework-digestauth] package which provides HTTP digest authentication support for REST framework. + +## Django OAuth Toolkit + +The [Django OAuth Toolkit][django-oauth-toolkit] package provides OAuth 2.0 support, and works with Python 2.7 and Python 3.3+. The package is maintained by [Evonove][evonove] and uses the excelllent [OAuthLib][oauthlib]. The package is well documented, and comes as a recommended alternative for OAuth 2.0 support. + +## Django OAuth2 Consumer + +The [Django OAuth2 Consumer][doac] library from [Rediker Software][rediker] is another package that provides [OAuth 2.0 support for REST framework][doac-rest-framework]. The package includes token scoping permissions on tokens, which allows finer-grained access to your API. [cite]: http://jacobian.org/writing/rest-worst-practices/ +[http401]: http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.2 +[http403]: http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.4 [basicauth]: http://tools.ietf.org/html/rfc2617 [oauth]: http://oauth.net/2/ [permission]: permissions.md [throttling]: throttling.md +[csrf-ajax]: https://docs.djangoproject.com/en/dev/ref/contrib/csrf/#ajax +[mod_wsgi_official]: http://code.google.com/p/modwsgi/wiki/ConfigurationDirectives#WSGIPassAuthorization +[custom-user-model]: https://docs.djangoproject.com/en/dev/topics/auth/customizing/#specifying-a-custom-user-model +[south-dependencies]: http://south.readthedocs.org/en/latest/dependencies.html +[juanriaza]: https://github.com/juanriaza +[djangorestframework-digestauth]: https://github.com/juanriaza/django-rest-framework-digestauth +[oauth-1.0a]: http://oauth.net/core/1.0a +[django-oauth-plus]: http://code.larlet.fr/django-oauth-plus +[django-oauth2-provider]: https://github.com/caffeinehit/django-oauth2-provider +[django-oauth2-provider-docs]: https://django-oauth2-provider.readthedocs.org/en/latest/ +[rfc6749]: http://tools.ietf.org/html/rfc6749 +[django-oauth-toolkit]: https://github.com/evonove/django-oauth-toolkit +[evonove]: https://github.com/evonove/ +[oauthlib]: https://github.com/idan/oauthlib +[doac]: https://github.com/Rediker-Software/doac +[rediker]: https://github.com/Rediker-Software +[doac-rest-framework]: https://github.com/Rediker-Software/doac/blob/master/docs/integrations.md# diff --git a/docs/api-guide/content-negotiation.md b/docs/api-guide/content-negotiation.md index 10288c94..94dd59ca 100644 --- a/docs/api-guide/content-negotiation.md +++ b/docs/api-guide/content-negotiation.md @@ -43,13 +43,19 @@ This is a valid approach as the HTTP spec deliberately underspecifies how a serv It's unlikely that you'll want to provide a custom content negotiation scheme for REST framework, but you can do so if needed. To implement a custom content negotiation scheme override `BaseContentNegotiation`. -REST framework's content negotiation classes handle selection of both the appropriate parser for the request, and the appropriate renderer for the response, so you should implement both the `.select_parser(request, parsers)` and `.select_renderer(request, renderers, format_suffix)` methods. +REST framework's content negotiation classes handle selection of both the appropriate parser for the request, and the appropriate renderer for the response, so you should implement both the `.select_parser(request, parsers)` and `.select_renderer(request, renderers, format_suffix)` methods. + +The `select_parser()` method should return one of the parser instances from the list of available parsers, or `None` if none of the parsers can handle the incoming request. + +The `select_renderer()` method should return a two-tuple of (renderer instance, media type), or raise a `NotAcceptable` exception. ## Example The following is a custom content negotiation class which ignores the client request when selecting the appropriate parser or renderer. + from rest_framework.negotiation import BaseContentNegotiation + class IgnoreClientContentNegotiation(BaseContentNegotiation): def select_parser(self, request, parsers): """ @@ -61,6 +67,31 @@ request when selecting the appropriate parser or renderer. """ Select the first renderer in the `.renderer_classes` list. """ - return renderers[0] + return (renderers[0], renderers[0].media_type) + +## Setting the content negotiation + +The default content negotiation class may be set globally, using the `DEFAULT_CONTENT_NEGOTIATION_CLASS` setting. For example, the following settings would use our example `IgnoreClientContentNegotiation` class. + + REST_FRAMEWORK = { + 'DEFAULT_CONTENT_NEGOTIATION_CLASS': 'myapp.negotiation.IgnoreClientContentNegotiation', + } + +You can also set the content negotiation used for an individual view, or viewset, using the `APIView` class based views. + + from myapp.negotiation import IgnoreClientContentNegotiation + from rest_framework.response import Response + from rest_framework.views import APIView + + class NoNegotiationView(APIView): + """ + An example view that does not perform content negotiation. + """ + content_negotiation_class = IgnoreClientContentNegotiation + + def get(self, request, format=None): + return Response({ + 'accepted media type': request.accepted_renderer.media_type + }) [accept-header]: http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html diff --git a/docs/api-guide/exceptions.md b/docs/api-guide/exceptions.md index ba57fde8..c46d415e 100644 --- a/docs/api-guide/exceptions.md +++ b/docs/api-guide/exceptions.md @@ -28,18 +28,61 @@ For example, the following request: Might receive an error response indicating that the `DELETE` method is not allowed on that resource: HTTP/1.1 405 Method Not Allowed - Content-Type: application/json; charset=utf-8 + Content-Type: application/json Content-Length: 42 - + {"detail": "Method 'DELETE' not allowed."} +## Custom exception handling + +You can implement custom exception handling by creating a handler function that converts exceptions raised in your API views into response objects. This allows you to control the style of error responses used by your API. + +The function must take a single argument, which is the exception to be handled, and should either return a `Response` object, or return `None` if the exception cannot be handled. If the handler returns `None` then the exception will be re-raised and Django will return a standard HTTP 500 'server error' response. + +For example, you might want to ensure that all error responses include the HTTP status code in the body of the response, like so: + + HTTP/1.1 405 Method Not Allowed + Content-Type: application/json + Content-Length: 62 + + {"status_code": 405, "detail": "Method 'DELETE' not allowed."} + +In order to alter the style of the response, you could write the following custom exception handler: + + from rest_framework.views import exception_handler + + def custom_exception_handler(exc): + # Call REST framework's default exception handler first, + # to get the standard error response. + response = exception_handler(exc) + + # Now add the HTTP status code to the response. + if response is not None: + response.data['status_code'] = response.status_code + + return response + +The exception handler must also be configured in your settings, using the `EXCEPTION_HANDLER` setting key. For example: + + REST_FRAMEWORK = { + 'EXCEPTION_HANDLER': 'my_project.my_app.utils.custom_exception_handler' + } + +If not specified, the `'EXCEPTION_HANDLER'` setting defaults to the standard exception handler provided by REST framework: + + REST_FRAMEWORK = { + 'EXCEPTION_HANDLER': 'rest_framework.views.exception_handler' + } + +Note that the exception handler will only be called for responses generated by raised exceptions. It will not be used for any responses returned directly by the view, such as the `HTTP_400_BAD_REQUEST` responses that are returned by the generic views when serializer validation fails. + --- # API Reference ## APIException -**Signature:** `APIException(detail=None)` +**Signature:** `APIException()` The **base class** for all exceptions raised inside REST framework. @@ -53,11 +96,27 @@ Raised if the request contains malformed data when accessing `request.DATA` or ` By default this exception results in a response with the HTTP status code "400 Bad Request". +## AuthenticationFailed + +**Signature:** `AuthenticationFailed(detail=None)` + +Raised when an incoming request includes incorrect authentication. + +By default this exception results in a response with the HTTP status code "401 Unauthenticated", but it may also result in a "403 Forbidden" response, depending on the authentication scheme in use. See the [authentication documentation][authentication] for more details. + +## NotAuthenticated + +**Signature:** `NotAuthenticated(detail=None)` + +Raised when an unauthenticated request fails the permission checks. + +By default this exception results in a response with the HTTP status code "401 Unauthenticated", but it may also result in a "403 Forbidden" response, depending on the authentication scheme in use. See the [authentication documentation][authentication] for more details. + ## PermissionDenied **Signature:** `PermissionDenied(detail=None)` -Raised when an incoming request fails the permission checks. +Raised when an authenticated request fails the permission checks. By default this exception results in a response with the HTTP status code "403 Forbidden". @@ -86,3 +145,4 @@ Raised when an incoming request fails the throttling checks. By default this exception results in a response with the HTTP status code "429 Too Many Requests". [cite]: http://www.doughellmann.com/articles/how-tos/python-exception-handling/index.html +[authentication]: authentication.md diff --git a/docs/api-guide/fields.md b/docs/api-guide/fields.md index 914d0861..e05c0306 100644 --- a/docs/api-guide/fields.md +++ b/docs/api-guide/fields.md @@ -2,11 +2,11 @@ # Serializer fields -> Flat is better than nested. +> Each field in a Form class is responsible not only for validating data, but also for "cleaning" it — normalizing it to a consistent format. > -> — [The Zen of Python][cite] +> — [Django documentation][cite] -Serializer fields handle converting between primative values and internal datatypes. They also deal with validating input values, as well as retrieving and setting the values from their parent objects. +Serializer fields handle converting between primitive values and internal datatypes. They also deal with validating input values, as well as retrieving and setting the values from their parent objects. --- @@ -16,7 +16,7 @@ Serializer fields handle converting between primative values and internal dataty ## Core arguments -Each serializer field class constructor takes at least these arguments. Some Field classes take additional, field-specific arguments, but the following should always be accepted: +Each serializer field class constructor takes at least these arguments. Some Field classes take additional, field-specific arguments, but the following should always be accepted: ### `source` @@ -28,7 +28,7 @@ Defaults to the name of the field. ### `read_only` -Set this to `True` to ensure that the field is used when serializing a representation, but is not used when updating an instance dureing deserialization. +Set this to `True` to ensure that the field is used when serializing a representation, but is not used when updating an instance during deserialization. Defaults to `False` @@ -41,7 +41,9 @@ Defaults to `True`. ### `default` -If set, this gives the default value that will be used for the field if none is supplied. If not set the default behaviour is to not populate the attribute at all. +If set, this gives the default value that will be used for the field if no input value is supplied. If not set the default behavior is to not populate the attribute at all. + +May be set to a function or other callable, in which case the value will be evaluated each time it is used. ### `validators` @@ -56,6 +58,13 @@ A dictionary of error codes to error messages. Used only if rendering the field to HTML. This argument sets the widget that should be used to render the field. +### `label` + +A short text string that may be used as the name of the field in HTML form fields or other descriptive elements. + +### `help_text` + +A text string that may be used as a description of the field in HTML form fields or other descriptive elements. --- @@ -69,6 +78,9 @@ A generic, **read-only** field. You can use this field for any attribute that d For example, using the following model. + from django.db import models + from django.utils.timezone import now + class Account(models.Model): owner = models.ForeignKey('auth.user') name = models.CharField(max_length=100) @@ -76,13 +88,14 @@ For example, using the following model. payment_expiry = models.DateTimeField() def has_expired(self): - now = datetime.datetime.now() - return now > self.payment_expiry + return now() > self.payment_expiry A serializer definition that looked like this: + from rest_framework import serializers + class AccountSerializer(serializers.HyperlinkedModelSerializer): - expired = Field(source='has_expired') + expired = serializers.Field(source='has_expired') class Meta: fields = ('url', 'owner', 'name', 'expired') @@ -96,19 +109,38 @@ Would produce output similar to: 'expired': True } -By default, the `Field` class will perform a basic translation of the source value into primative datatypes, falling back to unicode representations of complex datatypes when necessary. +By default, the `Field` class will perform a basic translation of the source value into primitive datatypes, falling back to unicode representations of complex datatypes when necessary. -You can customize this behaviour by overriding the `.to_native(self, value)` method. +You can customize this behavior by overriding the `.to_native(self, value)` method. ## WritableField -A field that supports both read and write operations. By itself `WriteableField` does not perform any translation of input values into a given type. You won't typically use this field directly, but you may want to override it and implement the `.to_native(self, value)` and `.from_native(self, value)` methods. +A field that supports both read and write operations. By itself `WritableField` does not perform any translation of input values into a given type. You won't typically use this field directly, but you may want to override it and implement the `.to_native(self, value)` and `.from_native(self, value)` methods. ## ModelField A generic field that can be tied to any arbitrary model field. The `ModelField` class delegates the task of serialization/deserialization to it's associated model field. This field can be used to create serializer fields for custom model fields, without having to create a new custom serializer field. -**Signature:** `ModelField(model_field=<Django ModelField class>)` +The `ModelField` class is generally intended for internal use, but can be used by your API if needed. In order to properly instantiate a `ModelField`, it must be passed a field that is attached to an instantiated model. For example: `ModelField(model_field=MyModel()._meta.get_field('custom_field'))` + +**Signature:** `ModelField(model_field=<Django ModelField instance>)` + +## SerializerMethodField + +This is a read-only field. It gets its value by calling a method on the serializer class it is attached to. It can be used to add any sort of data to the serialized representation of your object. The field's constructor accepts a single argument, which is the name of the method on the serializer to be called. The method should accept a single argument (in addition to `self`), which is the object being serialized. It should return whatever you want to be included in the serialized representation of the object. For example: + + from django.contrib.auth.models import User + from django.utils.timezone import now + from rest_framework import serializers + + class UserSerializer(serializers.ModelSerializer): + days_since_joined = serializers.SerializerMethodField('get_days_since_joined') + + class Meta: + model = User + + def get_days_since_joined(self, obj): + return (now() - obj.date_joined).days --- @@ -133,7 +165,7 @@ or `django.db.models.fields.TextField`. ## URLField -Corresponds to `django.db.models.fields.URLField`. Uses Django's `django.core.validators.URLValidator` for validation. +Corresponds to `django.db.models.fields.URLField`. Uses Django's `django.core.validators.URLValidator` for validation. **Signature:** `CharField(max_length=200, min_length=None)` @@ -153,11 +185,15 @@ A text representation, validates the text to be a valid e-mail address. Corresponds to `django.db.models.fields.EmailField` -## DateField +## RegexField -A date representation. +A text representation, that validates the given value matches against a certain regular expression. -Corresponds to `django.db.models.fields.DateField` +Uses Django's `django.core.validators.RegexValidator` for validation. + +Corresponds to `django.forms.fields.RegexField` + +**Signature:** `RegexField(regex, max_length=None, min_length=None)` ## DateTimeField @@ -165,184 +201,147 @@ A date and time representation. Corresponds to `django.db.models.fields.DateTimeField` -## IntegerField - -An integer representation. - -Corresponds to `django.db.models.fields.IntegerField`, `django.db.models.fields.SmallIntegerField`, `django.db.models.fields.PositiveIntegerField` and `django.db.models.fields.PositiveSmallIntegerField` - -## FloatField - -A floating point representation. - -Corresponds to `django.db.models.fields.FloatField`. - -## FileField - -A file representation. Performs Django's standard FileField validation. - -Corresponds to `django.forms.fields.FileField`. - -**Signature:** `FileField(max_length=None, allow_empty_file=False)` - - - `max_length` designates the maximum length for the file name. - - - `allow_empty_file` designates if empty files are allowed. - -## ImageField +When using `ModelSerializer` or `HyperlinkedModelSerializer`, note that any model fields with `auto_now=True` or `auto_now_add=True` will use serializer fields that are `read_only=True` by default. -An image representation. +If you want to override this behavior, you'll need to declare the `DateTimeField` explicitly on the serializer. For example: -Corresponds to `django.forms.fields.ImageField`. + class CommentSerializer(serializers.ModelSerializer): + created = serializers.DateTimeField() -Requires the `PIL` package. + class Meta: + model = Comment -Signature and validation is the same as with `FileField`. +Note that by default, datetime representations are determined by the renderer in use, although this can be explicitly overridden as detailed below. ---- +In the case of JSON this means the default datetime representation uses the [ECMA 262 date time string specification][ecma262]. This is a subset of ISO 8601 which uses millisecond precision, and includes the 'Z' suffix for the UTC timezone, for example: `2013-01-29T12:34:56.123Z`. -**Note:** `FileFields` and `ImageFields` are only suitable for use with MultiPartParser, since eg json doesn't support file uploads. -Django's regular [FILE_UPLOAD_HANDLERS] are used for handling uploaded files. +**Signature:** `DateTimeField(format=None, input_formats=None)` ---- +* `format` - A string representing the output format. If not specified, this defaults to `None`, which indicates that Python `datetime` objects should be returned by `to_native`. In this case the datetime encoding will be determined by the renderer. +* `input_formats` - A list of strings representing the input formats which may be used to parse the date. If not specified, the `DATETIME_INPUT_FORMATS` setting will be used, which defaults to `['iso-8601']`. -# Relational Fields +DateTime format strings may either be [Python strftime formats][strftime] which explicitly specify the format, or the special string `'iso-8601'`, which indicates that [ISO 8601][iso8601] style datetimes should be used. (eg `'2013-01-29T12:34:56.000000Z'`) -Relational fields are used to represent model relationships. They can be applied to `ForeignKey`, `ManyToManyField` and `OneToOneField` relationships, as well as to reverse relationships, and custom relationships such as `GenericForeignKey`. +## DateField -## RelatedField +A date representation. -This field can be applied to any of the following: +Corresponds to `django.db.models.fields.DateField` -* A `ForeignKey` field. -* A `OneToOneField` field. -* A reverse OneToOne relationship -* Any other "to-one" relationship. +**Signature:** `DateField(format=None, input_formats=None)` -By default `RelatedField` will represent the target of the field using it's `__unicode__` method. +* `format` - A string representing the output format. If not specified, this defaults to `None`, which indicates that Python `date` objects should be returned by `to_native`. In this case the date encoding will be determined by the renderer. +* `input_formats` - A list of strings representing the input formats which may be used to parse the date. If not specified, the `DATE_INPUT_FORMATS` setting will be used, which defaults to `['iso-8601']`. -You can customise this behaviour by subclassing `ManyRelatedField`, and overriding the `.to_native(self, value)` method. +Date format strings may either be [Python strftime formats][strftime] which explicitly specify the format, or the special string `'iso-8601'`, which indicates that [ISO 8601][iso8601] style dates should be used. (eg `'2013-01-29'`) -## ManyRelatedField +## TimeField -This field can be applied to any of the following: - -* A `ManyToManyField` field. -* A reverse ManyToMany relationship. -* A reverse ForeignKey relationship -* Any other "to-many" relationship. +A time representation. -By default `ManyRelatedField` will represent the targets of the field using their `__unicode__` method. +Optionally takes `format` as parameter to replace the matching pattern. -For example, given the following models: +Corresponds to `django.db.models.fields.TimeField` - class TaggedItem(models.Model): - """ - Tags arbitrary model instances using a generic relation. - - See: https://docs.djangoproject.com/en/dev/ref/contrib/contenttypes/ - """ - tag = models.SlugField() - content_type = models.ForeignKey(ContentType) - object_id = models.PositiveIntegerField() - content_object = GenericForeignKey('content_type', 'object_id') - - def __unicode__(self): - return self.tag - - - class Bookmark(models.Model): - """ - A bookmark consists of a URL, and 0 or more descriptive tags. - """ - url = models.URLField() - tags = GenericRelation(TaggedItem) - -And a model serializer defined like this: +**Signature:** `TimeField(format=None, input_formats=None)` - class BookmarkSerializer(serializers.ModelSerializer): - tags = serializers.ManyRelatedField(source='tags') - - class Meta: - model = Bookmark - exclude = ('id',) +* `format` - A string representing the output format. If not specified, this defaults to `None`, which indicates that Python `time` objects should be returned by `to_native`. In this case the time encoding will be determined by the renderer. +* `input_formats` - A list of strings representing the input formats which may be used to parse the date. If not specified, the `TIME_INPUT_FORMATS` setting will be used, which defaults to `['iso-8601']`. -Then an example output format for a Bookmark instance would be: - - { - 'tags': [u'django', u'python'], - 'url': u'https://www.djangoproject.com/' - } +Time format strings may either be [Python strftime formats][strftime] which explicitly specify the format, or the special string `'iso-8601'`, which indicates that [ISO 8601][iso8601] style times should be used. (eg `'12:34:56.000000'`) -## PrimaryKeyRelatedField / ManyPrimaryKeyRelatedField +## IntegerField -`PrimaryKeyRelatedField` and `ManyPrimaryKeyRelatedField` will represent the target of the relationship using it's primary key. +An integer representation. -By default these fields are read-write, although you can change this behaviour using the `read_only` flag. +Corresponds to `django.db.models.fields.IntegerField`, `django.db.models.fields.SmallIntegerField`, `django.db.models.fields.PositiveIntegerField` and `django.db.models.fields.PositiveSmallIntegerField` -**Arguments**: +## FloatField -* `queryset` - By default `ModelSerializer` classes will use the default queryset for the relationship. `Serializer` classes must either set a queryset explicitly, or set `read_only=True`. +A floating point representation. -## SlugRelatedField / ManySlugRelatedField +Corresponds to `django.db.models.fields.FloatField`. -`SlugRelatedField` and `ManySlugRelatedField` will represent the target of the relationship using a unique slug. +## DecimalField -By default these fields read-write, although you can change this behaviour using the `read_only` flag. +A decimal representation. -**Arguments**: +Corresponds to `django.db.models.fields.DecimalField`. -* `slug_field` - The field on the target that should be used to represent it. This should be a field that uniquely identifies any given instance. For example, `username`. -* `queryset` - By default `ModelSerializer` classes will use the default queryset for the relationship. `Serializer` classes must either set a queryset explicitly, or set `read_only=True`. +## FileField -## HyperlinkedRelatedField / ManyHyperlinkedRelatedField +A file representation. Performs Django's standard FileField validation. -`HyperlinkedRelatedField` and `ManyHyperlinkedRelatedField` will represent the target of the relationship using a hyperlink. +Corresponds to `django.forms.fields.FileField`. -By default, `HyperlinkedRelatedField` is read-write, although you can change this behaviour using the `read_only` flag. +**Signature:** `FileField(max_length=None, allow_empty_file=False)` -**Arguments**: + - `max_length` designates the maximum length for the file name. + + - `allow_empty_file` designates if empty files are allowed. -* `view_name` - The view name that should be used as the target of the relationship. **required**. -* `format` - If using format suffixes, hyperlinked fields will use the same format suffix for the target unless overridden by using the `format` argument. -* `queryset` - By default `ModelSerializer` classes will use the default queryset for the relationship. `Serializer` classes must either set a queryset explicitly, or set `read_only=True`. -* `slug_field` - The field on the target that should be used for the lookup. Default is `'slug'`. -* `pk_url_kwarg` - The named url parameter for the pk field lookup. Default is `pk`. -* `slug_url_kwarg` - The named url parameter for the slug field lookup. Default is to use the same value as given for `slug_field`. +## ImageField -## HyperLinkedIdentityField +An image representation. -This field can be applied as an identity relationship, such as the `'url'` field on a HyperlinkedModelSerializer. +Corresponds to `django.forms.fields.ImageField`. -This field is always read-only. +Requires either the `Pillow` package or `PIL` package. The `Pillow` package is recommended, as `PIL` is no longer actively maintained. -**Arguments**: +Signature and validation is the same as with `FileField`. -* `view_name` - The view name that should be used as the target of the relationship. **required**. -* `format` - If using format suffixes, hyperlinked fields will use the same format suffix for the target unless overridden by using the `format` argument. -* `slug_field` - The field on the target that should be used for the lookup. Default is `'slug'`. -* `pk_url_kwarg` - The named url parameter for the pk field lookup. Default is `pk`. -* `slug_url_kwarg` - The named url parameter for the slug field lookup. Default is to use the same value as given for `slug_field`. +--- -# Other Fields +**Note:** `FileFields` and `ImageFields` are only suitable for use with MultiPartParser, since e.g. json doesn't support file uploads. +Django's regular [FILE_UPLOAD_HANDLERS] are used for handling uploaded files. -## SerializerMethodField +--- -This is a read-only field. It gets its value by calling a method on the serializer class it is attached to. It can be used to add any sort of data to the serialized representation of your object. The field's constructor accepts a single argument, which is the name of the method on the serializer to be called. The method should accept a single argument (in addition to `self`), which is the object being serialized. It should return whatever you want to be included in the serialized representation of the object. For example: +# Custom fields - from rest_framework import serializers - from django.contrib.auth.models import User - from django.utils.timezone import now +If you want to create a custom field, you'll probably want to override either one or both of the `.to_native()` and `.from_native()` methods. These two methods are used to convert between the initial datatype, and a primitive, serializable datatype. Primitive datatypes may be any of a number, string, date/time/datetime or None. They may also be any list or dictionary like object that only contains other primitive objects. - class UserSerializer(serializers.ModelSerializer): +The `.to_native()` method is called to convert the initial datatype into a primitive, serializable datatype. The `from_native()` method is called to restore a primitive datatype into it's initial representation. - days_since_joined = serializers.SerializerMethodField('get_days_since_joined') +## Examples - class Meta: - model = User +Let's look at an example of serializing a class that represents an RGB color value: - def get_days_since_joined(self, obj): - return (now() - obj.date_joined).days + class Color(object): + """ + A color represented in the RGB colorspace. + """ + def __init__(self, red, green, blue): + assert(red >= 0 and green >= 0 and blue >= 0) + assert(red < 256 and green < 256 and blue < 256) + self.red, self.green, self.blue = red, green, blue -[cite]: http://www.python.org/dev/peps/pep-0020/ + class ColourField(serializers.WritableField): + """ + Color objects are serialized into "rgb(#, #, #)" notation. + """ + def to_native(self, obj): + return "rgb(%d, %d, %d)" % (obj.red, obj.green, obj.blue) + + def from_native(self, data): + data = data.strip('rgb(').rstrip(')') + red, green, blue = [int(col) for col in data.split(',')] + return Color(red, green, blue) + + +By default field values are treated as mapping to an attribute on the object. If you need to customize how the field value is accessed and set you need to override `.field_to_native()` and/or `.field_from_native()`. + +As an example, let's create a field that can be used represent the class name of the object being serialized: + + class ClassNameField(serializers.Field): + def field_to_native(self, obj, field_name): + """ + Serialize the object's class name. + """ + return obj.__class__ + +[cite]: https://docs.djangoproject.com/en/dev/ref/forms/api/#django.forms.Form.cleaned_data [FILE_UPLOAD_HANDLERS]: https://docs.djangoproject.com/en/dev/ref/settings/#std:setting-FILE_UPLOAD_HANDLERS +[ecma262]: http://ecma-international.org/ecma-262/5.1/#sec-15.9.1.15 +[strftime]: http://docs.python.org/2/library/datetime.html#strftime-and-strptime-behavior +[iso8601]: http://www.w3.org/TR/NOTE-datetime diff --git a/docs/api-guide/filtering.md b/docs/api-guide/filtering.md index 53ea7cbc..a0132ffc 100644 --- a/docs/api-guide/filtering.md +++ b/docs/api-guide/filtering.md @@ -2,13 +2,13 @@ # Filtering -> The root QuerySet provided by the Manager describes all objects in the database table. Usually, though, you'll need to select only a subset of the complete set of objects. +> The root QuerySet provided by the Manager describes all objects in the database table. Usually, though, you'll need to select only a subset of the complete set of objects. > > — [Django documentation][cite] The default behavior of REST framework's generic list views is to return the entire queryset for a model manager. Often you will want your API to restrict the items that are returned by the queryset. -The simplest way to filter the queryset of any view that subclasses `MultipleObjectAPIView` is to override the `.get_queryset()` method. +The simplest way to filter the queryset of any view that subclasses `GenericAPIView` is to override the `.get_queryset()` method. Overriding this method allows you to customize the queryset returned by the view in a number of different ways. @@ -20,8 +20,11 @@ You can do so by filtering based on the value of `request.user`. For example: + from myapp.models import Purchase + from myapp.serializers import PurchaseSerializer + from rest_framework import generics + class PurchaseList(generics.ListAPIView) - model = Purchase serializer_class = PurchaseSerializer def get_queryset(self): @@ -44,7 +47,6 @@ For example if your URL config contained an entry like this: You could then write a view that returned a purchase queryset filtered by the username portion of the URL: class PurchaseList(generics.ListAPIView) - model = Purchase serializer_class = PurchaseSerializer def get_queryset(self): @@ -62,7 +64,6 @@ A final example of filtering the initial queryset would be to determine the init We can override `.get_queryset()` to deal with URLs such as `http://example.com/api/purchases?username=denvercoder9`, and filter the queryset only if the `username` parameter is included in the URL: class PurchaseList(generics.ListAPIView) - model = Purchase serializer_class = PurchaseSerializer def get_queryset(self): @@ -80,82 +81,262 @@ We can override `.get_queryset()` to deal with URLs such as `http://example.com/ # Generic Filtering -As well as being able to override the default queryset, REST framework also includes support for generic filtering backends that allow you to easily construct complex filters that can be specified by the client using query parameters. - -REST framework supports pluggable backends to implement filtering, and provides an implementation which uses the [django-filter] package. +As well as being able to override the default queryset, REST framework also includes support for generic filtering backends that allow you to easily construct complex searches and filters. -To use REST framework's filtering backend, first install `django-filter`. - - pip install django-filter +## Setting filter backends -You must also set the filter backend to `DjangoFilterBackend` in your settings: +The default filter backends may be set globally, using the `DEFAULT_FILTER_BACKENDS` setting. For example. REST_FRAMEWORK = { - 'FILTER_BACKEND': 'rest_framework.filters.DjangoFilterBackend' + 'DEFAULT_FILTER_BACKENDS': ('rest_framework.filters.DjangoFilterBackend',) } +You can also set the filter backends on a per-view, or per-viewset basis, +using the `GenericAPIView` class based views. -## Specifying filter fields + from django.contrib.auth.models import User + from myapp.serializers import UserSerializer + from rest_framework import filters + from rest_framework import generics -If all you need is simple equality-based filtering, you can set a `filter_fields` attribute on the view, listing the set of fields you wish to filter against. + class UserListView(generics.ListAPIView): + queryset = User.objects.all() + serializer = UserSerializer + filter_backends = (filters.DjangoFilterBackend,) - class ProductList(generics.ListAPIView): +## Filtering and object lookups + +Note that if a filter backend is configured for a view, then as well as being used to filter list views, it will also be used to filter the querysets used for returning a single object. + +For instance, given the previous example, and a product with an id of `4675`, the following URL would either return the corresponding object, or return a 404 response, depending on if the filtering conditions were met by the given product instance: + + http://example.com/api/products/4675/?category=clothing&max_price=10.00 + +## Overriding the initial queryset + +Note that you can use both an overridden `.get_queryset()` and generic filtering together, and everything will work as expected. For example, if `Product` had a many-to-many relationship with `User`, named `purchase`, you might want to write a view like this: + + class PurchasedProductsList(generics.ListAPIView): + """ + Return a list of all the products that the authenticated + user has ever purchased, with optional filtering. + """ model = Product serializer_class = ProductSerializer + filter_class = ProductFilter + + def get_queryset(self): + user = self.request.user + return user.purchase_set.all() + +--- + +# API Guide + +## DjangoFilterBackend + +The `DjangoFilterBackend` class supports highly customizable field filtering, using the [django-filter package][django-filter]. + +To use REST framework's `DjangoFilterBackend`, first install `django-filter`. + + pip install django-filter + + +#### Specifying filter fields + +If all you need is simple equality-based filtering, you can set a `filter_fields` attribute on the view, or viewset, listing the set of fields you wish to filter against. + + class ProductList(generics.ListAPIView): + queryset = Product.objects.all() + serializer_class = ProductSerializer filter_fields = ('category', 'in_stock') This will automatically create a `FilterSet` class for the given fields, and will allow you to make requests such as: http://example.com/api/products?category=clothing&in_stock=True -## Specifying a FilterSet +#### Specifying a FilterSet For more advanced filtering requirements you can specify a `FilterSet` class that should be used by the view. For example: + import django_filters + from myapp.models import Product + from myapp.serializers import ProductSerializer + from rest_framework import generics + class ProductFilter(django_filters.FilterSet): - min_price = django_filters.NumberFilter(lookup_type='gte') - max_price = django_filters.NumberFilter(lookup_type='lte') + min_price = django_filters.NumberFilter(name="price", lookup_type='gte') + max_price = django_filters.NumberFilter(name="price", lookup_type='lte') class Meta: model = Product fields = ['category', 'in_stock', 'min_price', 'max_price'] class ProductList(generics.ListAPIView): - model = Product + queryset = Product.objects.all() serializer_class = ProductSerializer filter_class = ProductFilter + Which will allow you to make requests such as: http://example.com/api/products?category=clothing&max_price=10.00 +You can also span relationships using `django-filter`, let's assume that each +product has foreign key to `Manufacturer` model, so we create filter that +filters using `Manufacturer` name. For example: + + import django_filters + from myapp.models import Product + from myapp.serializers import ProductSerializer + from rest_framework import generics + + class ProductFilter(django_filters.FilterSet): + class Meta: + model = Product + fields = ['category', 'in_stock', 'manufacturer__name`] + +This enables us to make queries like: + + http://example.com/api/products?manufacturer__name=foo + +This is nice, but it shows underlying model structure in REST API, which may +be undesired, but you can use: + + import django_filters + from myapp.models import Product + from myapp.serializers import ProductSerializer + from rest_framework import generics + + class ProductFilter(django_filters.FilterSet): + + manufacturer = django_filters.CharFilter(name="manufacturer__name") + + class Meta: + model = Product + fields = ['category', 'in_stock', 'manufacturer`] + +And now you can execute: + + http://example.com/api/products?manufacturer=foo + For more details on using filter sets see the [django-filter documentation][django-filter-docs]. --- **Hints & Tips** -* By default filtering is not enabled. If you want to use `DjangoFilterBackend` remember to make sure it is installed by using the `'FILTER_BACKEND'` setting. +* By default filtering is not enabled. If you want to use `DjangoFilterBackend` remember to make sure it is installed by using the `'DEFAULT_FILTER_BACKENDS'` setting. * When using boolean fields, you should use the values `True` and `False` in the URL query parameters, rather than `0`, `1`, `true` or `false`. (The allowed boolean values are currently hardwired in Django's [NullBooleanSelect implementation][nullbooleanselect].) * `django-filter` supports filtering across relationships, using Django's double-underscore syntax. +* For Django 1.3 support, make sure to install `django-filter` version 0.5.4, as later versions drop support for 1.3. --- -## Overriding the initial queryset - -Note that you can use both an overridden `.get_queryset()` and generic filtering together, and everything will work as expected. For example, if `Product` had a many-to-many relationship with `User`, named `purchase`, you might want to write a view like this: +## SearchFilter + +The `SearchFilter` class supports simple single query parameter based searching, and is based on the [Django admin's search functionality][search-django-admin]. + +The `SearchFilter` class will only be applied if the view has a `search_fields` attribute set. The `search_fields` attribute should be a list of names of text type fields on the model, such as `CharField` or `TextField`. + + class UserListView(generics.ListAPIView): + queryset = User.objects.all() + serializer = UserSerializer + filter_backends = (filters.SearchFilter,) + search_fields = ('username', 'email') + +This will allow the client to filter the items in the list by making queries such as: + + http://example.com/api/users?search=russell + +You can also perform a related lookup on a ForeignKey or ManyToManyField with the lookup API double-underscore notation: + + search_fields = ('username', 'email', 'profile__profession') + +By default, searches will use case-insensitive partial matches. The search parameter may contain multiple search terms, which should be whitespace and/or comma separated. If multiple search terms are used then objects will be returned in the list only if all the provided terms are matched. + +The search behavior may be restricted by prepending various characters to the `search_fields`. + +* '^' Starts-with search. +* '=' Exact matches. +* '@' Full-text search. (Currently only supported Django's MySQL backend.) + +For example: + + search_fields = ('=username', '=email') + +For more details, see the [Django documentation][search-django-admin]. + +--- + +## OrderingFilter + +The `OrderingFilter` class supports simple query parameter controlled ordering of results. To specify the result order, set a query parameter named `'ordering'` to the required field name. For example: + + http://example.com/api/users?ordering=username + +The client may also specify reverse orderings by prefixing the field name with '-', like so: + + http://example.com/api/users?ordering=-username + +Multiple orderings may also be specified: + + http://example.com/api/users?ordering=account,username + +If an `ordering` attribute is set on the view, this will be used as the default ordering. + +Typically you'd instead control this by setting `order_by` on the initial queryset, but using the `ordering` parameter on the view allows you to specify the ordering in a way that it can then be passed automatically as context to a rendered template. This makes it possible to automatically render column headers differently if they are being used to order the results. + + class UserListView(generics.ListAPIView): + queryset = User.objects.all() + serializer = UserSerializer + filter_backends = (filters.OrderingFilter,) + ordering = ('username',) + +The `ordering` attribute may be either a string or a list/tuple of strings. + +--- + +## DjangoObjectPermissionsFilter + +The `DjangoObjectPermissionsFilter` is intended to be used together with the [`django-guardian`][guardian] package, with custom `'view'` permissions added. The filter will ensure that querysets only returns objects for which the user has the appropriate view permission. + +This filter class must be used with views that provide either a `queryset` or a `model` attribute. + +If you're using `DjangoObjectPermissionsFilter`, you'll probably also want to add an appropriate object permissions class, to ensure that users can only operate on instances if they have the appropriate object permissions. The easiest way to do this is to subclass `DjangoObjectPermissions` and add `'view'` permissions to the `perms_map` attribute. + +A complete example using both `DjangoObjectPermissionsFilter` and `DjangoObjectPermissions` might look something like this. + +**permissions.py**: + + class CustomObjectPermissions(permissions.DjangoObjectPermissions): + """ + Similar to `DjangoObjectPermissions`, but adding 'view' permissions. + """ + perms_map = { + 'GET': ['%(app_label)s.view_%(model_name)s'], + 'OPTIONS': ['%(app_label)s.view_%(model_name)s'], + 'HEAD': ['%(app_label)s.view_%(model_name)s'], + 'POST': ['%(app_label)s.add_%(model_name)s'], + 'PUT': ['%(app_label)s.change_%(model_name)s'], + 'PATCH': ['%(app_label)s.change_%(model_name)s'], + 'DELETE': ['%(app_label)s.delete_%(model_name)s'], + } + +**views.py**: + + class EventViewSet(viewsets.ModelViewSet): + """ + Viewset that only lists events if user has 'view' permissions, and only + allows operations on individual events if user has appropriate 'view', 'add', + 'change' or 'delete' permissions. + """ + queryset = Event.objects.all() + serializer = EventSerializer + filter_backends = (filters.DjangoObjectPermissionsFilter,) + permission_classes = (myapp.permissions.CustomObjectPermissions,) + +For more information on adding `'view'` permissions for models, see the [relevant section][view-permissions] of the `django-guardian` documentation, and [this blogpost][view-permissions-blogpost]. - class PurchasedProductsList(generics.ListAPIView): - """ - Return a list of all the products that the authenticated - user has ever purchased, with optional filtering. - """ - model = Product - serializer_class = ProductSerializer - filter_class = ProductFilter - - def get_queryset(self): - user = self.request.user - return user.purchase_set.all() --- # Custom generic filtering @@ -164,15 +345,26 @@ You can also provide your own generic filtering backend, or write an installable To do so override `BaseFilterBackend`, and override the `.filter_queryset(self, request, queryset, view)` method. The method should return a new, filtered queryset. -To install the filter backend, set the `'FILTER_BACKEND'` key in your `'REST_FRAMEWORK'` setting, using the dotted import path of the filter backend class. +As well as allowing clients to perform searches and filtering, generic filter backends can be useful for restricting which objects should be visible to any given request or user. -For example: +## Example - REST_FRAMEWORK = { - 'FILTER_BACKEND': 'custom_filters.CustomFilterBackend' - } +For example, you might need to restrict users to only being able to see objects they created. + + class IsOwnerFilterBackend(filters.BaseFilterBackend): + """ + Filter that only allows users to see their own objects. + """ + def filter_queryset(self, request, queryset, view): + return queryset.filter(owner=request.user) + +We could achieve the same behavior by overriding `get_queryset()` on the views, but using a filter backend allows you to more easily add this restriction to multiple views, or to apply it across the entire API. [cite]: https://docs.djangoproject.com/en/dev/topics/db/queries/#retrieving-specific-objects-with-filters [django-filter]: https://github.com/alex/django-filter [django-filter-docs]: https://django-filter.readthedocs.org/en/latest/index.html -[nullbooleanselect]: https://github.com/django/django/blob/master/django/forms/widgets.py
\ No newline at end of file +[guardian]: http://pythonhosted.org/django-guardian/ +[view-permissions]: http://pythonhosted.org/django-guardian/userguide/assign.html +[view-permissions-blogpost]: http://blog.nyaruka.com/adding-a-view-permission-to-django-models +[nullbooleanselect]: https://github.com/django/django/blob/master/django/forms/widgets.py +[search-django-admin]: https://docs.djangoproject.com/en/dev/ref/contrib/admin/#django.contrib.admin.ModelAdmin.search_fields diff --git a/docs/api-guide/format-suffixes.md b/docs/api-guide/format-suffixes.md index 6d5feba4..529738e3 100644 --- a/docs/api-guide/format-suffixes.md +++ b/docs/api-guide/format-suffixes.md @@ -29,18 +29,27 @@ Example: urlpatterns = patterns('blog.views', url(r'^/$', 'api_root'), - url(r'^comment/$', 'comment_root'), - url(r'^comment/(?P<pk>[0-9]+)/$', 'comment_instance') + url(r'^comments/$', 'comment_list'), + url(r'^comments/(?P<pk>[0-9]+)/$', 'comment_detail') ) urlpatterns = format_suffix_patterns(urlpatterns, allowed=['json', 'html']) -When using `format_suffix_patterns`, you must make sure to add the `'format'` keyword argument to the corresponding views. For example. +When using `format_suffix_patterns`, you must make sure to add the `'format'` keyword argument to the corresponding views. For example: - @api_view(('GET',)) - def api_root(request, format=None): + @api_view(('GET', 'POST')) + def comment_list(request, format=None): # do stuff... +Or with class based views: + + class CommentList(APIView): + def get(self, request, format=None): + # do stuff... + + def post(self, request, format=None): + # do stuff... + The name of the kwarg used may be modified by using the `FORMAT_SUFFIX_KWARG` setting. Also note that `format_suffix_patterns` does not support descending into `include` URL patterns. @@ -49,13 +58,13 @@ Also note that `format_suffix_patterns` does not support descending into `includ ## Accept headers vs. format suffixes -There seems to be a view among some of the Web community that filename extensions are not a RESTful pattern, and that `HTTP Accept` headers should always be used instead. +There seems to be a view among some of the Web community that filename extensions are not a RESTful pattern, and that `HTTP Accept` headers should always be used instead. It is actually a misconception. For example, take the following quote from Roy Fielding discussing the relative merits of query parameter media-type indicators vs. file extension media-type indicators: -“That's why I always prefer extensions. Neither choice has anything to do with REST.” — Roy Fielding, [REST discuss mailing list][cite2] +“That's why I always prefer extensions. Neither choice has anything to do with REST.” — Roy Fielding, [REST discuss mailing list][cite2] The quote does not mention Accept headers, but it does make it clear that format suffixes should be considered an acceptable pattern. [cite]: http://tech.groups.yahoo.com/group/rest-discuss/message/5857 -[cite2]: http://tech.groups.yahoo.com/group/rest-discuss/message/14844
\ No newline at end of file +[cite2]: http://tech.groups.yahoo.com/group/rest-discuss/message/14844 diff --git a/docs/api-guide/generic-views.md b/docs/api-guide/generic-views.md index 428323b8..83c3e45f 100644..100755 --- a/docs/api-guide/generic-views.md +++ b/docs/api-guide/generic-views.md @@ -7,18 +7,23 @@ > > — [Django Documentation][cite] -One of the key benefits of class based views is the way they allow you to compose bits of reusable behaviour. REST framework takes advantage of this by providing a number of pre-built views that provide for commonly used patterns. +One of the key benefits of class based views is the way they allow you to compose bits of reusable behaviour. REST framework takes advantage of this by providing a number of pre-built views that provide for commonly used patterns. The generic views provided by REST framework allow you to quickly build API views that map closely to your database models. -If the generic views don't suit the needs of your API, you can drop down to using the regular `APIView` class, or reuse the mixins and base classes used by the generic views to compose your own set of reusable generic views. +If the generic views don't suit the needs of your API, you can drop down to using the regular `APIView` class, or reuse the mixins and base classes used by the generic views to compose your own set of reusable generic views. ## Examples Typically when using the generic views, you'll override the view, and set several class attributes. + from django.contrib.auth.models import User + from myapp.serializers import UserSerializer + from rest_framework import generics + from rest_framework.permissions import IsAdminUser + class UserList(generics.ListCreateAPIView): - model = User + queryset = User.objects.all() serializer_class = UserSerializer permission_classes = (IsAdminUser,) paginate_by = 100 @@ -26,138 +31,172 @@ Typically when using the generic views, you'll override the view, and set severa For more complex cases you might also want to override various methods on the view class. For example. class UserList(generics.ListCreateAPIView): - model = User + queryset = User.objects.all() serializer_class = UserSerializer permission_classes = (IsAdminUser,) - - def get_paginate_by(self, queryset): + + def get_paginate_by(self): """ Use smaller pagination for HTML representations. """ - page_size_param = self.request.QUERY_PARAMS.get('page_size') - if page_size_param: - return int(page_size_param) + if self.request.accepted_renderer.format == 'html': + return 20 return 100 For very simple cases you might want to pass through any class attributes using the `.as_view()` method. For example, your URLconf might include something the following entry. - url(r'^/users/', ListCreateAPIView.as_view(model=User) name='user-list') + url(r'^/users/', ListCreateAPIView.as_view(model=User), name='user-list') --- # API Reference -The following classes are the concrete generic views. If you're using generic views this is normally the level you'll be working at unless you need heavily customized behavior. +## GenericAPIView -## CreateAPIView +This class extends REST framework's `APIView` class, adding commonly required behavior for standard list and detail views. -Used for **create-only** endpoints. +Each of the concrete generic views provided is built by combining `GenericAPIView`, with one or more mixin classes. -Provides `post` method handlers. +### Attributes -Extends: [GenericAPIView], [CreateModelMixin] +**Basic settings**: -## ListAPIView +The following attributes control the basic view behavior. -Used for **read-only** endpoints to represent a **collection of model instances**. +* `queryset` - The queryset that should be used for returning objects from this view. Typically, you must either set this attribute, or override the `get_queryset()` method. +* `serializer_class` - The serializer class that should be used for validating and deserializing input, and for serializing output. Typically, you must either set this attribute, or override the `get_serializer_class()` method. +* `lookup_field` - The model field that should be used to for performing object lookup of individual model instances. Defaults to `'pk'`. Note that when using hyperlinked APIs you'll need to ensure that *both* the API views *and* the serializer classes set the lookup fields if you need to use a custom value. +* `lookup_url_kwarg` - The URL keyword argument that should be used for object lookup. The URL conf should include a keyword argument corresponding to this value. If unset this defaults to using the same value as `lookup_field`. -Provides a `get` method handler. +**Shortcuts**: -Extends: [MultipleObjectAPIView], [ListModelMixin] +* `model` - This shortcut may be used instead of setting either (or both) of the `queryset`/`serializer_class` attributes, although using the explicit style is generally preferred. If used instead of `serializer_class`, then then `DEFAULT_MODEL_SERIALIZER_CLASS` setting will determine the base serializer class. Note that `model` is only ever used for generating a default queryset or serializer class - the `queryset` and `serializer_class` attributes are always preferred if provided. -## RetrieveAPIView +**Pagination**: -Used for **read-only** endpoints to represent a **single model instance**. +The following attributes are used to control pagination when used with list views. -Provides a `get` method handler. +* `paginate_by` - The size of pages to use with paginated data. If set to `None` then pagination is turned off. If unset this uses the same value as the `PAGINATE_BY` setting, which defaults to `None`. +* `paginate_by_param` - The name of a query parameter, which can be used by the client to override the default page size to use for pagination. If unset this uses the same value as the `PAGINATE_BY_PARAM` setting, which defaults to `None`. +* `pagination_serializer_class` - The pagination serializer class to use when determining the style of paginated responses. Defaults to the same value as the `DEFAULT_PAGINATION_SERIALIZER_CLASS` setting. +* `page_kwarg` - The name of a URL kwarg or URL query parameter which can be used by the client to control which page is requested. Defaults to `'page'`. -Extends: [SingleObjectAPIView], [RetrieveModelMixin] +**Filtering**: -## DestroyAPIView +* `filter_backends` - A list of filter backend classes that should be used for filtering the queryset. Defaults to the same value as the `DEFAULT_FILTER_BACKENDS` setting. -Used for **delete-only** endpoints for a **single model instance**. +### Methods -Provides a `delete` method handler. +**Base methods**: -Extends: [SingleObjectAPIView], [DestroyModelMixin] +#### `get_queryset(self)` -## UpdateAPIView +Returns the queryset that should be used for list views, and that should be used as the base for lookups in detail views. Defaults to returning the queryset specified by the `queryset` attribute, or the default queryset for the model if the `model` shortcut is being used. -Used for **update-only** endpoints for a **single model instance**. +May be overridden to provide dynamic behavior such as returning a queryset that is specific to the user making the request. -Provides a `put` method handler. +For example: -Extends: [SingleObjectAPIView], [UpdateModelMixin] + def get_queryset(self): + user = self.request.user + return user.accounts.all() -## ListCreateAPIView +#### `get_object(self)` -Used for **read-write** endpoints to represent a **collection of model instances**. +Returns an object instance that should be used for detail views. Defaults to using the `lookup_field` parameter to filter the base queryset. -Provides `get` and `post` method handlers. +May be overridden to provide more complex behavior such as object lookups based on more than one URL kwarg. -Extends: [MultipleObjectAPIView], [ListModelMixin], [CreateModelMixin] +For example: -## RetrieveDestroyAPIView + def get_object(self): + queryset = self.get_queryset() + filter = {} + for field in self.multiple_lookup_fields: + filter[field] = self.kwargs[field] -Used for **read or delete** endpoints to represent a **single model instance**. + obj = get_object_or_404(queryset, **filter) + self.check_object_permissions(self.request, obj) + return obj -Provides `get` and `delete` method handlers. +Note that if your API doesn't include any object level permissions, you may optionally exclude the ``self.check_object_permissions, and simply return the object from the `get_object_or_404` lookup. -Extends: [SingleObjectAPIView], [RetrieveModelMixin], [DestroyModelMixin] +#### `get_filter_backends(self)` -## RetrieveUpdateDestroyAPIView +Returns the classes that should be used to filter the queryset. Defaults to returning the `filter_backends` attribute. -Used for **read-write-delete** endpoints to represent a **single model instance**. +May be override to provide more complex behavior with filters, as using different (or even exlusive) lists of filter_backends depending on different criteria. -Provides `get`, `put` and `delete` method handlers. +For example: -Extends: [SingleObjectAPIView], [RetrieveModelMixin], [UpdateModelMixin], [DestroyModelMixin] + def get_filter_backends(self): + if "geo_route" in self.request.QUERY_PARAMS: + return (GeoRouteFilter, CategoryFilter) + elif "geo_point" in self.request.QUERY_PARAMS: + return (GeoPointFilter, CategoryFilter) ---- + return (CategoryFilter,) -# Base views +#### `get_serializer_class(self)` -Each of the generic views provided is built by combining one of the base views below, with one or more mixin classes. +Returns the class that should be used for the serializer. Defaults to returning the `serializer_class` attribute, or dynamically generating a serializer class if the `model` shortcut is being used. -## GenericAPIView +May be override to provide dynamic behavior such as using different serializers for read and write operations, or providing different serializers to different types of users. -Extends REST framework's `APIView` class, adding support for serialization of model instances and model querysets. +For example: -**Attributes**: + def get_serializer_class(self): + if self.request.user.is_staff: + return FullAccountSerializer + return BasicAccountSerializer -* `model` - The model that should be used for this view. Used as a fallback for determining the serializer if `serializer_class` is not set, and as a fallback for determining the queryset if `queryset` is not set. Otherwise not required. -* `serializer_class` - The serializer class that should be used for validating and deserializing input, and for serializing output. If unset, this defaults to creating a serializer class using `self.model`, with the `DEFAULT_MODEL_SERIALIZER_CLASS` setting as the base serializer class. +#### `get_paginate_by(self)` -## MultipleObjectAPIView +Returns the page size to use with pagination. By default this uses the `paginate_by` attribute, and may be overridden by the client if the `paginate_by_param` attribute is set. -Provides a base view for acting on a single object, by combining REST framework's `APIView`, and Django's [MultipleObjectMixin]. +You may want to override this method to provide more complex behavior such as modifying page sizes based on the media type of the response. -**See also:** ccbv.co.uk documentation for [MultipleObjectMixin][multiple-object-mixin-classy]. +For example: -**Attributes**: + def get_paginate_by(self): + if self.request.accepted_renderer.format == 'html': + return 20 + return 100 -* `queryset` - The queryset that should be used for returning objects from this view. If unset, defaults to the default queryset manager for `self.model`. -* `paginate_by` - The size of pages to use with paginated data. If set to `None` then pagination is turned off. If unset this uses the same value as the `PAGINATE_BY` setting, which defaults to `None`. -* `paginate_by_param` - The name of a query parameter, which can be used by the client to overide the default page size to use for pagination. If unset this uses the same value as the `PAGINATE_BY_PARAM` setting, which defaults to `None`. +**Save / deletion hooks**: + +The following methods are provided as placeholder interfaces. They contain empty implementations and are not called directly by `GenericAPIView`, but they are overridden and used by some of the mixin classes. + +* `pre_save(self, obj)` - A hook that is called before saving an object. +* `post_save(self, obj, created=False)` - A hook that is called after saving an object. +* `pre_delete(self, obj)` - A hook that is called before deleting an object. +* `post_delete(self, obj)` - A hook that is called after deleting an object. + +The `pre_save` method in particular is a useful hook for setting attributes that are implicit in the request, but are not part of the request data. For instance, you might set an attribute on the object based on the request user, or based on a URL keyword argument. -## SingleObjectAPIView + def pre_save(self, obj): + """ + Set the object's owner, based on the incoming request. + """ + obj.owner = self.request.user -Provides a base view for acting on a single object, by combining REST framework's `APIView`, and Django's [SingleObjectMixin]. +Remember that the `pre_save()` method is not called by `GenericAPIView` itself, but it is called by `create()` and `update()` methods on the `CreateModelMixin` and `UpdateModelMixin` classes. -**See also:** ccbv.co.uk documentation for [SingleObjectMixin][single-object-mixin-classy]. +**Other methods**: -**Attributes**: +You won't typically need to override the following methods, although you might need to call into them if you're writing custom views using `GenericAPIView`. -* `queryset` - The queryset that should be used when retrieving an object from this view. If unset, defaults to the default queryset manager for `self.model`. -* `pk_kwarg` - The URL kwarg that should be used to look up objects by primary key. Defaults to `'pk'`. [Can only be set to non-default on Django 1.4+] -* `slug_kwarg` - The URL kwarg that should be used to look up objects by a slug. Defaults to `'slug'`. [Can only be set to non-default on Django 1.4+] -* `slug_field` - The field on the model that should be used to look up objects by a slug. If used, this should typically be set to a field with `unique=True`. Defaults to `'slug'`. +* `get_serializer_context(self)` - Returns a dictionary containing any extra context that should be supplied to the serializer. Defaults to including `'request'`, `'view'` and `'format'` keys. +* `get_serializer(self, instance=None, data=None, files=None, many=False, partial=False)` - Returns a serializer instance. +* `get_pagination_serializer(self, page)` - Returns a serializer instance to use with paginated data. +* `paginate_queryset(self, queryset)` - Paginate a queryset if required, either returning a page object, or `None` if pagination is not configured for this view. +* `filter_queryset(self, queryset)` - Given a queryset, filter it with whichever filter backends are in use, returning a new queryset. --- # Mixins -The mixin classes provide the actions that are used to provide the basic view behaviour. Note that the mixin classes provide action methods rather than defining the handler methods such as `.get()` and `.post()` directly. This allows for more flexible composition of behaviour. +The mixin classes provide the actions that are used to provide the basic view behavior. Note that the mixin classes provide action methods rather than defining the handler methods such as `.get()` and `.post()` directly. This allows for more flexible composition of behavior. ## ListModelMixin @@ -165,9 +204,7 @@ Provides a `.list(request, *args, **kwargs)` method, that implements listing a q If the queryset is populated, this returns a `200 OK` response, with a serialized representation of the queryset as the body of the response. The response data may optionally be paginated. -If the queryset is empty this returns a `200 OK` reponse, unless the `.allow_empty` attribute on the view is set to `False`, in which case it will return a `404 Not Found`. - -Should be mixed in with [MultipleObjectAPIView]. +If the queryset is empty this returns a `200 OK` response, unless the `.allow_empty` attribute on the view is set to `False`, in which case it will return a `404 Not Found`. ## CreateModelMixin @@ -177,47 +214,159 @@ If an object is created this returns a `201 Created` response, with a serialized If the request data provided for creating the object was invalid, a `400 Bad Request` response will be returned, with the error details as the body of the response. -Should be mixed in with any [GenericAPIView]. - ## RetrieveModelMixin Provides a `.retrieve(request, *args, **kwargs)` method, that implements returning an existing model instance in a response. -If an object can be retrieve this returns a `200 OK` response, with a serialized representation of the object as the body of the response. Otherwise it will return a `404 Not Found`. - -Should be mixed in with [SingleObjectAPIView]. +If an object can be retrieved this returns a `200 OK` response, with a serialized representation of the object as the body of the response. Otherwise it will return a `404 Not Found`. ## UpdateModelMixin Provides a `.update(request, *args, **kwargs)` method, that implements updating and saving an existing model instance. +Also provides a `.partial_update(request, *args, **kwargs)` method, which is similar to the `update` method, except that all fields for the update will be optional. This allows support for HTTP `PATCH` requests. + If an object is updated this returns a `200 OK` response, with a serialized representation of the object as the body of the response. If an object is created, for example when making a `DELETE` request followed by a `PUT` request to the same URL, this returns a `201 Created` response, with a serialized representation of the object as the body of the response. If the request data provided for updating the object was invalid, a `400 Bad Request` response will be returned, with the error details as the body of the response. -Should be mixed in with [SingleObjectAPIView]. - ## DestroyModelMixin Provides a `.destroy(request, *args, **kwargs)` method, that implements deletion of an existing model instance. If an object is deleted this returns a `204 No Content` response, otherwise it will return a `404 Not Found`. -Should be mixed in with [SingleObjectAPIView]. +--- + +# Concrete View Classes + +The following classes are the concrete generic views. If you're using generic views this is normally the level you'll be working at unless you need heavily customized behavior. + +## CreateAPIView + +Used for **create-only** endpoints. + +Provides a `post` method handler. + +Extends: [GenericAPIView], [CreateModelMixin] + +## ListAPIView + +Used for **read-only** endpoints to represent a **collection of model instances**. + +Provides a `get` method handler. + +Extends: [GenericAPIView], [ListModelMixin] + +## RetrieveAPIView + +Used for **read-only** endpoints to represent a **single model instance**. + +Provides a `get` method handler. + +Extends: [GenericAPIView], [RetrieveModelMixin] + +## DestroyAPIView + +Used for **delete-only** endpoints for a **single model instance**. + +Provides a `delete` method handler. + +Extends: [GenericAPIView], [DestroyModelMixin] + +## UpdateAPIView + +Used for **update-only** endpoints for a **single model instance**. + +Provides `put` and `patch` method handlers. + +Extends: [GenericAPIView], [UpdateModelMixin] + +## ListCreateAPIView + +Used for **read-write** endpoints to represent a **collection of model instances**. + +Provides `get` and `post` method handlers. + +Extends: [GenericAPIView], [ListModelMixin], [CreateModelMixin] + +## RetrieveUpdateAPIView + +Used for **read or update** endpoints to represent a **single model instance**. + +Provides `get`, `put` and `patch` method handlers. + +Extends: [GenericAPIView], [RetrieveModelMixin], [UpdateModelMixin] + +## RetrieveDestroyAPIView + +Used for **read or delete** endpoints to represent a **single model instance**. + +Provides `get` and `delete` method handlers. + +Extends: [GenericAPIView], [RetrieveModelMixin], [DestroyModelMixin] + +## RetrieveUpdateDestroyAPIView + +Used for **read-write-delete** endpoints to represent a **single model instance**. + +Provides `get`, `put`, `patch` and `delete` method handlers. + +Extends: [GenericAPIView], [RetrieveModelMixin], [UpdateModelMixin], [DestroyModelMixin] + +--- + +# Customizing the generic views + +Often you'll want to use the existing generic views, but use some slightly customized behavior. If you find yourself reusing some bit of customized behavior in multiple places, you might want to refactor the behavior into a common class that you can then just apply to any view or viewset as needed. + +## Creating custom mixins + +For example, if you need to lookup objects based on multiple fields in the URL conf, you could create a mixin class like the following: + + class MultipleFieldLookupMixin(object): + """ + Apply this mixin to any view or viewset to get multiple field filtering + based on a `lookup_fields` attribute, instead of the default single field filtering. + """ + def get_object(self): + queryset = self.get_queryset() # Get the base queryset + queryset = self.filter_queryset(queryset) # Apply any filter backends + filter = {} + for field in self.lookup_fields: + filter[field] = self.kwargs[field] + return get_object_or_404(queryset, **filter) # Lookup the object + +You can then simply apply this mixin to a view or viewset anytime you need to apply the custom behavior. + + class RetrieveUserView(MultipleFieldLookupMixin, generics.RetrieveAPIView): + queryset = User.objects.all() + serializer_class = UserSerializer + lookup_fields = ('account', 'username') + +Using custom mixins is a good option if you have custom behavior that needs to be used + +## Creating custom base classes + +If you are using a mixin across multiple views, you can take this a step further and create your own set of base views that can then be used throughout your project. For example: + + class BaseRetrieveView(MultipleFieldLookupMixin, + generics.RetrieveAPIView): + pass + + class BaseRetrieveUpdateDestroyView(MultipleFieldLookupMixin, + generics.RetrieveUpdateDestroyAPIView): + pass + +Using custom base classes is a good option if you have custom behavior that consistently needs to be repeated across a large number of views throughout your project. [cite]: https://docs.djangoproject.com/en/dev/ref/class-based-views/#base-vs-generic-views -[MultipleObjectMixin]: https://docs.djangoproject.com/en/dev/ref/class-based-views/mixins-multiple-object/ -[SingleObjectMixin]: https://docs.djangoproject.com/en/dev/ref/class-based-views/mixins-single-object/ -[multiple-object-mixin-classy]: http://ccbv.co.uk/projects/Django/1.4/django.views.generic.list/MultipleObjectMixin/ -[single-object-mixin-classy]: http://ccbv.co.uk/projects/Django/1.4/django.views.generic.detail/SingleObjectMixin/ [GenericAPIView]: #genericapiview -[SingleObjectAPIView]: #singleobjectapiview -[MultipleObjectAPIView]: #multipleobjectapiview [ListModelMixin]: #listmodelmixin [CreateModelMixin]: #createmodelmixin [RetrieveModelMixin]: #retrievemodelmixin [UpdateModelMixin]: #updatemodelmixin -[DestroyModelMixin]: #destroymodelmixin
\ No newline at end of file +[DestroyModelMixin]: #destroymodelmixin diff --git a/docs/api-guide/pagination.md b/docs/api-guide/pagination.md index ab335e6e..0829589f 100644 --- a/docs/api-guide/pagination.md +++ b/docs/api-guide/pagination.md @@ -13,6 +13,7 @@ REST framework includes a `PaginationSerializer` class that makes it easy to ret Let's start by taking a look at an example from the Django documentation. from django.core.paginator import Paginator + objects = ['john', 'paul', 'george', 'ringo'] paginator = Paginator(objects, 2) page = paginator.page(1) @@ -22,6 +23,7 @@ Let's start by taking a look at an example from the Django documentation. At this point we've got a page object. If we wanted to return this page object as a JSON response, we'd need to provide the client with context such as next and previous links, so that it would be able to page through the remaining results. from rest_framework.pagination import PaginationSerializer + serializer = PaginationSerializer(instance=page) serializer.data # {'count': 4, 'next': '?page=2', 'previous': None, 'results': [u'john', u'paul']} @@ -37,7 +39,7 @@ We could now return that data in a `Response` object, and it would be rendered i ## Paginating QuerySets -Our first example worked because we were using primative objects. If we wanted to paginate a queryset or other complex data, we'd need to specify a serializer to use to serialize the result set itself with. +Our first example worked because we were using primitive objects. If we wanted to paginate a queryset or other complex data, we'd need to specify a serializer to use to serialize the result set itself. We can do this using the `object_serializer_class` attribute on the inner `Meta` class of the pagination serializer. For example. @@ -83,19 +85,24 @@ We could now use our pagination serializer in a view like this. The generic class based views `ListAPIView` and `ListCreateAPIView` provide pagination of the returned querysets by default. You can customise this behaviour by altering the pagination style, by modifying the default number of results, by allowing clients to override the page size using a query parameter, or by turning pagination off completely. -The default pagination style may be set globally, using the `DEFAULT_PAGINATION_SERIALIZER_CLASS`, `PAGINATE_BY` and `PAGINATE_BY_PARAM` settings. For example. +The default pagination style may be set globally, using the `DEFAULT_PAGINATION_SERIALIZER_CLASS`, `PAGINATE_BY`, `PAGINATE_BY_PARAM`, and `MAX_PAGINATE_BY` settings. For example. REST_FRAMEWORK = { - 'PAGINATE_BY': 10, - 'PAGINATE_BY_PARAM': 'page_size' + 'PAGINATE_BY': 10, # Default to 10 + 'PAGINATE_BY_PARAM': 'page_size', # Allow client to override, using `?page_size=xxx`. + 'MAX_PAGINATE_BY': 100 # Maximum limit allowed when using `?page_size=xxx`. } You can also set the pagination style on a per-view basis, using the `ListAPIView` generic class-based view. class PaginatedListView(ListAPIView): - model = ExampleModel + queryset = ExampleModel.objects.all() + serializer_class = ExampleModelSerializer paginate_by = 10 paginate_by_param = 'page_size' + max_paginate_by = 100 + +Note that using a `paginate_by` value of `None` will turn off pagination for the view. For more complex requirements such as serialization that differs depending on the requested media type you can override the `.get_paginate_by()` and `.get_pagination_serializer_class()` methods. @@ -111,9 +118,12 @@ You can also override the name used for the object list field, by setting the `r For example, to nest a pair of links labelled 'prev' and 'next', and set the name for the results field to 'objects', you might use something like this. + from rest_framework import pagination + from rest_framework import serializers + class LinksSerializer(serializers.Serializer): - next = pagination.NextURLField(source='*') - prev = pagination.PreviousURLField(source='*') + next = pagination.NextPageField(source='*') + prev = pagination.PreviousPageField(source='*') class CustomPaginationSerializer(pagination.BasePaginationSerializer): links = LinksSerializer(source='*') # Takes the page object as the source @@ -132,7 +142,7 @@ To have your custom pagination serializer be used by default, use the `DEFAULT_P Alternatively, to set your custom pagination serializer on a per-view basis, use the `pagination_serializer_class` attribute on a generic class based view: - class PaginatedListView(ListAPIView): + class PaginatedListView(generics.ListAPIView): model = ExampleModel pagination_serializer_class = CustomPaginationSerializer paginate_by = 10 diff --git a/docs/api-guide/parsers.md b/docs/api-guide/parsers.md index 185b616c..1030fcb6 100644 --- a/docs/api-guide/parsers.md +++ b/docs/api-guide/parsers.md @@ -14,6 +14,16 @@ REST framework includes a number of built in Parser classes, that allow you to a The set of valid parsers for a view is always defined as a list of classes. When either `request.DATA` or `request.FILES` is accessed, REST framework will examine the `Content-Type` header on the incoming request, and determine which parser to use to parse the request content. +--- + +**Note**: When developing client applications always remember to make sure you're setting the `Content-Type` header when sending data in an HTTP request. + +If you don't set the content type, most clients will default to using `'application/x-www-form-urlencoded'`, which may not be what you wanted. + +As an example, if you are sending `json` encoded data using jQuery with the [.ajax() method][jquery-ajax], you should make sure to include the `contentType: 'application/json'` setting. + +--- + ## Setting the parsers The default set of parsers may be set globally, using the `DEFAULT_PARSER_CLASSES` setting. For example, the following settings would allow requests with `YAML` content. @@ -24,7 +34,12 @@ The default set of parsers may be set globally, using the `DEFAULT_PARSER_CLASSE ) } -You can also set the renderers used for an individual view, using the `APIView` class based views. +You can also set the parsers used for an individual view, or viewset, +using the `APIView` class based views. + + from rest_framework.parsers import YAMLParser + from rest_framework.response import Response + from rest_framework.views import APIView class ExampleView(APIView): """ @@ -59,6 +74,8 @@ Parses `JSON` request content. Parses `YAML` request content. +Requires the `pyyaml` package to be installed. + **.media_type**: `application/yaml` ## XMLParser @@ -69,6 +86,8 @@ Note that the `XML` markup language is typically used as the base language for m If you are considering using `XML` for your API, you may want to consider implementing a custom renderer and parser for your specific requirements, and using an existing domain-specific media-type, or creating your own custom XML-based media-type. +Requires the `defusedxml` package to be installed. + **.media_type**: `application/xml` ## FormParser @@ -87,6 +106,33 @@ You will typically want to use both `FormParser` and `MultiPartParser` together **.media_type**: `multipart/form-data` +## FileUploadParser + +Parses raw file upload content. The `request.DATA` property will be an empty `QueryDict`, and `request.FILES` will be a dictionary with a single key `'file'` containing the uploaded file. + +If the view used with `FileUploadParser` is called with a `filename` URL keyword argument, then that argument will be used as the filename. If it is called without a `filename` URL keyword argument, then the client must set the filename in the `Content-Disposition` HTTP header. For example `Content-Disposition: attachment; filename=upload.jpg`. + +**.media_type**: `*/*` + +##### Notes: + +* The `FileUploadParser` is for usage with native clients that can upload the file as a raw data request. For web-based uploads, or for native clients with multipart upload support, you should use the `MultiPartParser` parser instead. +* Since this parser's `media_type` matches any content type, `FileUploadParser` should generally be the only parser set on an API view. +* `FileUploadParser` respects Django's standard `FILE_UPLOAD_HANDLERS` setting, and the `request.upload_handlers` attribute. See the [Django documentation][upload-handlers] for more details. + +##### Basic usage example: + + class FileUploadView(views.APIView): + parser_classes = (FileUploadParser,) + + def put(self, request, filename, format=None): + file_obj = request.FILES['file'] + # ... + # do some staff with uploaded file + # ... + return Response(status=204) + + --- # Custom parsers @@ -130,33 +176,19 @@ The following is an example plaintext parser that will populate the `request.DAT """ return stream.read() -## Uploading file content - -If your custom parser needs to support file uploads, you may return a `DataAndFiles` object from the `.parse()` method. `DataAndFiles` should be instantiated with two arguments. The first argument will be used to populate the `request.DATA` property, and the second argument will be used to populate the `request.FILES` property. - -For example: +--- - class SimpleFileUploadParser(BaseParser): - """ - A naive raw file upload parser. - """ - media_type = '*/*' # Accept anything +# Third party packages - def parse(self, stream, media_type=None, parser_context=None): - content = stream.read() - name = 'example.dat' - content_type = 'application/octet-stream' - size = len(content) - charset = 'utf-8' +The following third party packages are also available. - # Write a temporary file based on the request content - temp = tempfile.NamedTemporaryFile(delete=False) - temp.write(content) - uploaded = UploadedFile(temp, name, content_type, size, charset) +## MessagePack - # Return the uploaded file - data = {} - files = {name: uploaded} - return DataAndFiles(data, files) +[MessagePack][messagepack] is a fast, efficient binary serialization format. [Juan Riaza][juanriaza] maintains the [djangorestframework-msgpack][djangorestframework-msgpack] package which provides MessagePack renderer and parser support for REST framework. +[jquery-ajax]: http://api.jquery.com/jQuery.ajax/ [cite]: https://groups.google.com/d/topic/django-developers/dxI4qVzrBY4/discussion +[upload-handlers]: https://docs.djangoproject.com/en/dev/topics/http/file-uploads/#upload-handlers +[messagepack]: https://github.com/juanriaza/django-rest-framework-msgpack +[juanriaza]: https://github.com/juanriaza +[djangorestframework-msgpack]: https://github.com/juanriaza/django-rest-framework-msgpack diff --git a/docs/api-guide/permissions.md b/docs/api-guide/permissions.md index 1a746fb6..871de84e 100644 --- a/docs/api-guide/permissions.md +++ b/docs/api-guide/permissions.md @@ -2,7 +2,7 @@ # Permissions -> Authentication or identification by itself is not usually sufficient to gain access to information or code. For that, the entity requesting access must have authorization. +> Authentication or identification by itself is not usually sufficient to gain access to information or code. For that, the entity requesting access must have authorization. > > — [Apple Developer Documentation][cite] @@ -21,7 +21,20 @@ If any permission check fails an `exceptions.PermissionDenied` exception will be REST framework permissions also support object-level permissioning. Object level permissions are used to determine if a user should be allowed to act on a particular object, which will typically be a model instance. -Object level permissions are run by REST framework's generic views when `.get_object()` is called. As with view level permissions, an `exceptions.PermissionDenied` exception will be raised if the user is not allowed to act on the given object. +Object level permissions are run by REST framework's generic views when `.get_object()` is called. +As with view level permissions, an `exceptions.PermissionDenied` exception will be raised if the user is not allowed to act on the given object. + +If you're writing your own views and want to enforce object level permissions, +or if you override the `get_object` method on a generic view, then you'll need to explicitly call the `.check_object_permissions(request, obj)` method on the view at the point at which you've retrieved the object. + +This will either raise a `PermissionDenied` or `NotAuthenticated` exception, or simply return if the view has the appropriate permissions. + +For example: + + def get_object(self): + obj = get_object_or_404(self.get_queryset()) + self.check_object_permissions(self.request, obj) + return obj ## Setting the permission policy @@ -39,7 +52,12 @@ If not specified, this setting defaults to allowing unrestricted access: 'rest_framework.permissions.AllowAny', ) -You can also set the authentication policy on a per-view basis, using the `APIView` class based views. +You can also set the authentication policy on a per-view, or per-viewset basis, +using the `APIView` class based views. + + from rest_framework.permissions import IsAuthenticated + from rest_framework.responses import Response + from rest_framework.views import APIView class ExampleView(APIView): permission_classes = (IsAuthenticated,) @@ -53,7 +71,7 @@ You can also set the authentication policy on a per-view basis, using the `APIVi Or, if you're using the `@api_view` decorator with function based views. @api_view('GET') - @permission_classes(IsAuthenticated) + @permission_classes((IsAuthenticated, )) def example_view(request, format=None): content = { 'status': 'request was permitted' @@ -90,29 +108,138 @@ This permission is suitable if you want to your API to allow read permissions to ## DjangoModelPermissions -This permission class ties into Django's standard `django.contrib.auth` [model permissions][contribauth]. When applied to a view that has a `.model` property, authorization will only be granted if the user has the relevant model permissions assigned. +This permission class ties into Django's standard `django.contrib.auth` [model permissions][contribauth]. When applied to a view that has a `.model` property, authorization will only be granted if the user *is authenticated* and has the *relevant model permissions* assigned. * `POST` requests require the user to have the `add` permission on the model. * `PUT` and `PATCH` requests require the user to have the `change` permission on the model. * `DELETE` requests require the user to have the `delete` permission on the model. - + The default behaviour can also be overridden to support custom model permissions. For example, you might want to include a `view` model permission for `GET` requests. To use custom model permissions, override `DjangoModelPermissions` and set the `.perms_map` property. Refer to the source code for details. -The `DjangoModelPermissions` class also supports object-level permissions. Third-party authorization backends such as [django-guardian][guardian] that provide object-level permissions should work just fine with `DjangoModelPermissions` without any custom configuration required. +## DjangoModelPermissionsOrAnonReadOnly + +Similar to `DjangoModelPermissions`, but also allows unauthenticated users to have read-only access to the API. + +## DjangoObjectPermissions + +This permission class ties into Django's standard [object permissions framework][objectpermissions] that allows per-object permissions on models. In order to use this permission class, you'll also need to add a permission backend that supports object-level permissions, such as [django-guardian][guardian]. + +When applied to a view that has a `.model` property, authorization will only be granted if the user *is authenticated* and has the *relevant per-object permissions* and *relevant model permissions* assigned. + +* `POST` requests require the user to have the `add` permission on the model instance. +* `PUT` and `PATCH` requests require the user to have the `change` permission on the model instance. +* `DELETE` requests require the user to have the `delete` permission on the model instance. + +Note that `DjangoObjectPermissions` **does not** require the `django-guardian` package, and should support other object-level backends equally well. + +As with `DjangoModelPermissions` you can use custom model permissions by overriding `DjangoModelPermissions` and setting the `.perms_map` property. Refer to the source code for details. Note that if you add a custom `view` permission for `GET`, `HEAD` and `OPTIONS` requests, you'll probably also want to consider adding the `DjangoObjectPermissionsFilter` class to ensure that list endpoints only return results including objects for which the user has appropriate view permissions. + +## TokenHasReadWriteScope + +This permission class is intended for use with either of the `OAuthAuthentication` and `OAuth2Authentication` classes, and ties into the scoping that their backends provide. + +Requests with a safe methods of `GET`, `OPTIONS` or `HEAD` will be allowed if the authenticated token has read permission. + +Requests for `POST`, `PUT`, `PATCH` and `DELETE` will be allowed if the authenticated token has write permission. + +This permission class relies on the implementations of the [django-oauth-plus][django-oauth-plus] and [django-oauth2-provider][django-oauth2-provider] libraries, which both provide limited support for controlling the scope of access tokens: + +* `django-oauth-plus`: Tokens are associated with a `Resource` class which has a `name`, `url` and `is_readonly` properties. +* `django-oauth2-provider`: Tokens are associated with a bitwise `scope` attribute, that defaults to providing bitwise values for `read` and/or `write`. + +If you require more advanced scoping for your API, such as restricting tokens to accessing a subset of functionality of your API then you will need to provide a custom permission class. See the source of the `django-oauth-plus` or `django-oauth2-provider` package for more details on scoping token access. --- # Custom permissions -To implement a custom permission, override `BasePermission` and implement the `.has_permission(self, request, view, obj=None)` method. +To implement a custom permission, override `BasePermission` and implement either, or both, of the following methods: + +* `.has_permission(self, request, view)` +* `.has_object_permission(self, request, view, obj)` + +The methods should return `True` if the request should be granted access, and `False` otherwise. + +If you need to test if a request is a read operation or a write operation, you should check the request method against the constant `SAFE_METHODS`, which is a tuple containing `'GET'`, `'OPTIONS'` and `'HEAD'`. For example: + + if request.method in permissions.SAFE_METHODS: + # Check permissions for read-only request + else: + # Check permissions for write request + +--- + +**Note**: In versions 2.0 and 2.1, the signature for the permission checks always included an optional `obj` parameter, like so: `.has_permission(self, request, view, obj=None)`. The method would be called twice, first for the global permission checks, with no object supplied, and second for the object-level check when required. + +As of version 2.2 this signature has now been replaced with two separate method calls, which is more explicit and obvious. The old style signature continues to work, but its use will result in a `PendingDeprecationWarning`, which is silent by default. In 2.3 this will be escalated to a `DeprecationWarning`, and in 2.4 the old-style signature will be removed. + +For more details see the [2.2 release announcement][2.2-announcement]. + +--- + +## Examples + +The following is an example of a permission class that checks the incoming request's IP address against a blacklist, and denies the request if the IP has been blacklisted. + + from rest_framework import permissions + + class BlacklistPermission(permissions.BasePermission): + """ + Global permission check for blacklisted IPs. + """ + + def has_permission(self, request, view): + ip_addr = request.META['REMOTE_ADDR'] + blacklisted = Blacklist.objects.filter(ip_addr=ip_addr).exists() + return not blacklisted + +As well as global permissions, that are run against all incoming requests, you can also create object-level permissions, that are only run against operations that affect a particular object instance. For example: + + class IsOwnerOrReadOnly(permissions.BasePermission): + """ + Object-level permission to only allow owners of an object to edit it. + Assumes the model instance has an `owner` attribute. + """ + + def has_object_permission(self, request, view, obj): + # Read permissions are allowed to any request, + # so we'll always allow GET, HEAD or OPTIONS requests. + if request.method in permissions.SAFE_METHODS: + return True + + # Instance must have an attribute named `owner`. + return obj.owner == request.user + +Note that the generic views will check the appropriate object level permissions, but if you're writing your own custom views, you'll need to make sure you check the object level permission checks yourself. You can do so by calling `self.check_object_permissions(request, obj)` from the view once you have the object instance. This call will raise an appropriate `APIException` if any object-level permission checks fail, and will otherwise simply return. + +Also note that the generic views will only check the object-level permissions for views that retrieve a single model instance. If you require object-level filtering of list views, you'll need to filter the queryset separately. See the [filtering documentation][filtering] for more details. + +--- + +# Third party packages + +The following third party packages are also available. + +## DRF Any Permissions + +The [DRF Any Permissions][drf-any-permissions] packages provides a different permission behavior in contrast to REST framework. Instead of all specified permissions being required, only one of the given permissions has to be true in order to get access to the view. -The method should return `True` if the request should be granted access, and `False` otherwise. +## Composed Permissions +The [Composed Permissions][composed-permissions] package provides a simple way to define complex and multi-depth (with logic operators) permission objects, using small and reusable components. [cite]: https://developer.apple.com/library/mac/#documentation/security/Conceptual/AuthenticationAndAuthorizationGuide/Authorization/Authorization.html [authentication]: authentication.md [throttling]: throttling.md [contribauth]: https://docs.djangoproject.com/en/1.0/topics/auth/#permissions +[objectpermissions]: https://docs.djangoproject.com/en/dev/topics/auth/customizing/#handling-object-permissions [guardian]: https://github.com/lukaszb/django-guardian +[get_objects_for_user]: http://pythonhosted.org/django-guardian/api/guardian.shortcuts.html#get-objects-for-user +[django-oauth-plus]: http://code.larlet.fr/django-oauth-plus +[django-oauth2-provider]: https://github.com/caffeinehit/django-oauth2-provider +[2.2-announcement]: ../topics/2.2-announcement.md +[filtering]: filtering.md +[drf-any-permissions]: https://github.com/kevin-brown/drf-any-permissions +[composed-permissions]: https://github.com/niwibe/djangorestframework-composed-permissions diff --git a/docs/api-guide/relations.md b/docs/api-guide/relations.md new file mode 100644 index 00000000..b9d96b5e --- /dev/null +++ b/docs/api-guide/relations.md @@ -0,0 +1,448 @@ +<a class="github" href="relations.py"></a> + +# Serializer relations + +> Bad programmers worry about the code. +> Good programmers worry about data structures and their relationships. +> +> — [Linus Torvalds][cite] + + +Relational fields are used to represent model relationships. They can be applied to `ForeignKey`, `ManyToManyField` and `OneToOneField` relationships, as well as to reverse relationships, and custom relationships such as `GenericForeignKey`. + +--- + +**Note:** The relational fields are declared in `relations.py`, but by convention you should import them from the `serializers` module, using `from rest_framework import serializers` and refer to fields as `serializers.<FieldName>`. + +--- + +# API Reference + +In order to explain the various types of relational fields, we'll use a couple of simple models for our examples. Our models will be for music albums, and the tracks listed on each album. + + class Album(models.Model): + album_name = models.CharField(max_length=100) + artist = models.CharField(max_length=100) + + class Track(models.Model): + album = models.ForeignKey(Album, related_name='tracks') + order = models.IntegerField() + title = models.CharField(max_length=100) + duration = models.IntegerField() + + class Meta: + unique_together = ('album', 'order') + order_by = 'order' + + def __unicode__(self): + return '%d: %s' % (self.order, self.title) + +## RelatedField + +`RelatedField` may be used to represent the target of the relationship using its `__unicode__` method. + +For example, the following serializer. + + class AlbumSerializer(serializers.ModelSerializer): + tracks = RelatedField(many=True) + + class Meta: + model = Album + fields = ('album_name', 'artist', 'tracks') + +Would serialize to the following representation. + + { + 'album_name': 'Things We Lost In The Fire', + 'artist': 'Low', + 'tracks': [ + '1: Sunflower', + '2: Whitetail', + '3: Dinosaur Act', + ... + ] + } + +This field is read only. + +**Arguments**: + +* `many` - If applied to a to-many relationship, you should set this argument to `True`. + +## PrimaryKeyRelatedField + +`PrimaryKeyRelatedField` may be used to represent the target of the relationship using its primary key. + +For example, the following serializer: + + class AlbumSerializer(serializers.ModelSerializer): + tracks = serializers.PrimaryKeyRelatedField(many=True, read_only=True) + + class Meta: + model = Album + fields = ('album_name', 'artist', 'tracks') + +Would serialize to a representation like this: + + { + 'album_name': 'The Roots', + 'artist': 'Undun', + 'tracks': [ + 89, + 90, + 91, + ... + ] + } + +By default this field is read-write, although you can change this behavior using the `read_only` flag. + +**Arguments**: + +* `many` - If applied to a to-many relationship, you should set this argument to `True`. +* `required` - If set to `False`, the field will accept values of `None` or the empty-string for nullable relationships. +* `queryset` - By default `ModelSerializer` classes will use the default queryset for the relationship. `Serializer` classes must either set a queryset explicitly, or set `read_only=True`. + +## HyperlinkedRelatedField + +`HyperlinkedRelatedField` may be used to represent the target of the relationship using a hyperlink. + +For example, the following serializer: + + class AlbumSerializer(serializers.ModelSerializer): + tracks = serializers.HyperlinkedRelatedField(many=True, read_only=True, + view_name='track-detail') + + class Meta: + model = Album + fields = ('album_name', 'artist', 'tracks') + +Would serialize to a representation like this: + + { + 'album_name': 'Graceland', + 'artist': 'Paul Simon', + 'tracks': [ + 'http://www.example.com/api/tracks/45/', + 'http://www.example.com/api/tracks/46/', + 'http://www.example.com/api/tracks/47/', + ... + ] + } + +By default this field is read-write, although you can change this behavior using the `read_only` flag. + +**Arguments**: + +* `view_name` - The view name that should be used as the target of the relationship. **required**. +* `many` - If applied to a to-many relationship, you should set this argument to `True`. +* `required` - If set to `False`, the field will accept values of `None` or the empty-string for nullable relationships. +* `queryset` - By default `ModelSerializer` classes will use the default queryset for the relationship. `Serializer` classes must either set a queryset explicitly, or set `read_only=True`. +* `lookup_field` - The field on the target that should be used for the lookup. Should correspond to a URL keyword argument on the referenced view. Default is `'pk'`. +* `format` - If using format suffixes, hyperlinked fields will use the same format suffix for the target unless overridden by using the `format` argument. + +## SlugRelatedField + +`SlugRelatedField` may be used to represent the target of the relationship using a field on the target. + +For example, the following serializer: + + class AlbumSerializer(serializers.ModelSerializer): + tracks = serializers.SlugRelatedField(many=True, read_only=True, + slug_field='title') + + class Meta: + model = Album + fields = ('album_name', 'artist', 'tracks') + +Would serialize to a representation like this: + + { + 'album_name': 'Dear John', + 'artist': 'Loney Dear', + 'tracks': [ + 'Airport Surroundings', + 'Everything Turns to You', + 'I Was Only Going Out', + ... + ] + } + +By default this field is read-write, although you can change this behavior using the `read_only` flag. + +When using `SlugRelatedField` as a read-write field, you will normally want to ensure that the slug field corresponds to a model field with `unique=True`. + +**Arguments**: + +* `slug_field` - The field on the target that should be used to represent it. This should be a field that uniquely identifies any given instance. For example, `username`. **required** +* `many` - If applied to a to-many relationship, you should set this argument to `True`. +* `required` - If set to `False`, the field will accept values of `None` or the empty-string for nullable relationships. +* `queryset` - By default `ModelSerializer` classes will use the default queryset for the relationship. `Serializer` classes must either set a queryset explicitly, or set `read_only=True`. + +## HyperlinkedIdentityField + +This field can be applied as an identity relationship, such as the `'url'` field on a HyperlinkedModelSerializer. It can also be used for an attribute on the object. For example, the following serializer: + + class AlbumSerializer(serializers.HyperlinkedModelSerializer): + track_listing = serializers.HyperlinkedIdentityField(view_name='track-list') + + class Meta: + model = Album + fields = ('album_name', 'artist', 'track_listing') + +Would serialize to a representation like this: + + { + 'album_name': 'The Eraser', + 'artist': 'Thom Yorke', + 'track_listing': 'http://www.example.com/api/track_list/12/', + } + +This field is always read-only. + +**Arguments**: + +* `view_name` - The view name that should be used as the target of the relationship. **required**. +* `lookup_field` - The field on the target that should be used for the lookup. Should correspond to a URL keyword argument on the referenced view. Default is `'pk'`. +* `format` - If using format suffixes, hyperlinked fields will use the same format suffix for the target unless overridden by using the `format` argument. + +--- + +# Nested relationships + +Nested relationships can be expressed by using serializers as fields. + +If the field is used to represent a to-many relationship, you should add the `many=True` flag to the serializer field. + +## Example + +For example, the following serializer: + + class TrackSerializer(serializers.ModelSerializer): + class Meta: + model = Track + fields = ('order', 'title') + + class AlbumSerializer(serializers.ModelSerializer): + tracks = TrackSerializer(many=True) + + class Meta: + model = Album + fields = ('album_name', 'artist', 'tracks') + +Would serialize to a nested representation like this: + + { + 'album_name': 'The Grey Album', + 'artist': 'Danger Mouse', + 'tracks': [ + {'order': 1, 'title': 'Public Service Announcement'}, + {'order': 2, 'title': 'What More Can I Say'}, + {'order': 3, 'title': 'Encore'}, + ... + ], + } + +# Custom relational fields + +To implement a custom relational field, you should override `RelatedField`, and implement the `.to_native(self, value)` method. This method takes the target of the field as the `value` argument, and should return the representation that should be used to serialize the target. + +If you want to implement a read-write relational field, you must also implement the `.from_native(self, data)` method, and add `read_only = False` to the class definition. + +## Example + +For, example, we could define a relational field, to serialize a track to a custom string representation, using its ordering, title, and duration. + + import time + + class TrackListingField(serializers.RelatedField): + def to_native(self, value): + duration = time.strftime('%M:%S', time.gmtime(value.duration)) + return 'Track %d: %s (%s)' % (value.order, value.name, duration) + + class AlbumSerializer(serializers.ModelSerializer): + tracks = TrackListingField(many=True) + + class Meta: + model = Album + fields = ('album_name', 'artist', 'tracks') + +This custom field would then serialize to the following representation. + + { + 'album_name': 'Sometimes I Wish We Were an Eagle', + 'artist': 'Bill Callahan', + 'tracks': [ + 'Track 1: Jim Cain (04:39)', + 'Track 2: Eid Ma Clack Shaw (04:19)', + 'Track 3: The Wind and the Dove (04:34)', + ... + ] + } + +--- + +# Further notes + +## Reverse relations + +Note that reverse relationships are not automatically included by the `ModelSerializer` and `HyperlinkedModelSerializer` classes. To include a reverse relationship, you must explicitly add it to the fields list. For example: + + class AlbumSerializer(serializers.ModelSerializer): + class Meta: + fields = ('tracks', ...) + +You'll normally want to ensure that you've set an appropriate `related_name` argument on the relationship, that you can use as the field name. For example: + + class Track(models.Model): + album = models.ForeignKey(Album, related_name='tracks') + ... + +If you have not set a related name for the reverse relationship, you'll need to use the automatically generated related name in the `fields` argument. For example: + + class AlbumSerializer(serializers.ModelSerializer): + class Meta: + fields = ('track_set', ...) + +See the Django documentation on [reverse relationships][reverse-relationships] for more details. + +## Generic relationships + +If you want to serialize a generic foreign key, you need to define a custom field, to determine explicitly how you want serialize the targets of the relationship. + +For example, given the following model for a tag, which has a generic relationship with other arbitrary models: + + class TaggedItem(models.Model): + """ + Tags arbitrary model instances using a generic relation. + + See: https://docs.djangoproject.com/en/dev/ref/contrib/contenttypes/ + """ + tag_name = models.SlugField() + content_type = models.ForeignKey(ContentType) + object_id = models.PositiveIntegerField() + tagged_object = GenericForeignKey('content_type', 'object_id') + + def __unicode__(self): + return self.tag + +And the following two models, which may be have associated tags: + + class Bookmark(models.Model): + """ + A bookmark consists of a URL, and 0 or more descriptive tags. + """ + url = models.URLField() + tags = GenericRelation(TaggedItem) + + + class Note(models.Model): + """ + A note consists of some text, and 0 or more descriptive tags. + """ + text = models.CharField(max_length=1000) + tags = GenericRelation(TaggedItem) + +We could define a custom field that could be used to serialize tagged instances, using the type of each instance to determine how it should be serialized. + + class TaggedObjectRelatedField(serializers.RelatedField): + """ + A custom field to use for the `tagged_object` generic relationship. + """ + + def to_native(self, value): + """ + Serialize tagged objects to a simple textual representation. + """ + if isinstance(value, Bookmark): + return 'Bookmark: ' + value.url + elif isinstance(value, Note): + return 'Note: ' + value.text + raise Exception('Unexpected type of tagged object') + +If you need the target of the relationship to have a nested representation, you can use the required serializers inside the `.to_native()` method: + + def to_native(self, value): + """ + Serialize bookmark instances using a bookmark serializer, + and note instances using a note serializer. + """ + if isinstance(value, Bookmark): + serializer = BookmarkSerializer(value) + elif isinstance(value, Note): + serializer = NoteSerializer(value) + else: + raise Exception('Unexpected type of tagged object') + + return serializer.data + +Note that reverse generic keys, expressed using the `GenericRelation` field, can be serialized using the regular relational field types, since the type of the target in the relationship is always known. + +For more information see [the Django documentation on generic relations][generic-relations]. + +## ManyToManyFields with a Through Model + +By default, relational fields that target a ``ManyToManyField`` with a +``through`` model specified are set to read-only. + +If you explicitly specify a relational field pointing to a +``ManyToManyField`` with a through model, be sure to set ``read_only`` +to ``True``. + +## Advanced Hyperlinked fields + +If you have very specific requirements for the style of your hyperlinked relationships you can override `HyperlinkedRelatedField`. + +There are two methods you'll need to override. + +#### get_url(self, obj, view_name, request, format) + +This method should return the URL that corresponds to the given object. + +May raise a `NoReverseMatch` if the `view_name` and `lookup_field` +attributes are not configured to correctly match the URL conf. + +#### get_object(self, queryset, view_name, view_args, view_kwargs) + + +This method should the object that corresponds to the matched URL conf arguments. + +May raise an `ObjectDoesNotExist` exception. + +### Example + +For example, if all your object URLs used both a account and a slug in the the URL to reference the object, you might create a custom field like this: + + class CustomHyperlinkedField(serializers.HyperlinkedRelatedField): + def get_url(self, obj, view_name, request, format): + kwargs = {'account': obj.account, 'slug': obj.slug} + return reverse(view_name, kwargs=kwargs, request=request, format=format) + + def get_object(self, queryset, view_name, view_args, view_kwargs): + account = view_kwargs['account'] + slug = view_kwargs['slug'] + return queryset.get(account=account, slug=slug) + +--- + +## Deprecated APIs + +The following classes have been deprecated, in favor of the `many=<bool>` syntax. +They continue to function, but their usage will raise a `PendingDeprecationWarning`, which is silent by default. + +* `ManyRelatedField` +* `ManyPrimaryKeyRelatedField` +* `ManyHyperlinkedRelatedField` +* `ManySlugRelatedField` + +The `null=<bool>` flag has been deprecated in favor of the `required=<bool>` flag. It will continue to function, but will raise a `PendingDeprecationWarning`. + +In the 2.3 release, these warnings will be escalated to a `DeprecationWarning`, which is loud by default. +In the 2.4 release, these parts of the API will be removed entirely. + +For more details see the [2.2 release announcement][2.2-announcement]. + +[cite]: http://lwn.net/Articles/193245/ +[reverse-relationships]: https://docs.djangoproject.com/en/dev/topics/db/queries/#following-relationships-backward +[generic-relations]: https://docs.djangoproject.com/en/dev/ref/contrib/contenttypes/#id1 +[2.2-announcement]: ../topics/2.2-announcement.md diff --git a/docs/api-guide/renderers.md b/docs/api-guide/renderers.md index 374ff0ab..cf200569 100644 --- a/docs/api-guide/renderers.md +++ b/docs/api-guide/renderers.md @@ -14,7 +14,7 @@ The set of valid renderers for a view is always defined as a list of classes. W The basic process of content negotiation involves examining the request's `Accept` header, to determine which media types it expects in the response. Optionally, format suffixes on the URL may be used to explicitly request a particular representation. For example the URL `http://example.com/api/users_count.json` might be an endpoint that always returns JSON data. -For more information see the documentation on [content negotation][conneg]. +For more information see the documentation on [content negotiation][conneg]. ## Setting the renderers @@ -27,13 +27,19 @@ The default set of renderers may be set globally, using the `DEFAULT_RENDERER_CL ) } -You can also set the renderers used for an individual view, using the `APIView` class based views. +You can also set the renderers used for an individual view, or viewset, +using the `APIView` class based views. + + from django.contrib.auth.models import User + from rest_framework.renderers import JSONRenderer, YAMLRenderer + from rest_framework.response import Response + from rest_framework.views import APIView class UserCountView(APIView): """ - A view that returns the count of active users, in JSON or JSONp. + A view that returns the count of active users, in JSON or YAML. """ - renderer_classes = (JSONRenderer, JSONPRenderer) + renderer_classes = (JSONRenderer, YAMLRenderer) def get(self, request, format=None): user_count = User.objects.filter(active=True).count() @@ -56,7 +62,7 @@ Or, if you're using the `@api_view` decorator with function based views. It's important when specifying the renderer classes for your API to think about what priority you want to assign to each media type. If a client underspecifies the representations it can accept, such as sending an `Accept: */*` header, or not including an `Accept` header at all, then REST framework will select the first renderer in the list to use for the response. -For example if your API serves JSON responses and the HTML browseable API, you might want to make `JSONRenderer` your default renderer, in order to send `JSON` responses to clients that do not specify an `Accept` header. +For example if your API serves JSON responses and the HTML browsable API, you might want to make `JSONRenderer` your default renderer, in order to send `JSON` responses to clients that do not specify an `Accept` header. If your API includes views that can serve both regular webpages and API responses depending on the request, then you might consider making `TemplateHTMLRenderer` your default renderer, in order to play nicely with older browsers that send [broken accept headers][browser-accept-headers]. @@ -66,34 +72,78 @@ If your API includes views that can serve both regular webpages and API response ## JSONRenderer -Renders the request data into `JSON`. +Renders the request data into `JSON`, using utf-8 encoding. + +Note that non-ascii characters will be rendered using JSON's `\uXXXX` character escape. For example: + + {"unicode black star": "\u2605"} + +The client may additionally include an `'indent'` media type parameter, in which case the returned `JSON` will be indented. For example `Accept: application/json; indent=4`. + + { + "unicode black star": "\u2605" + } + +**.media_type**: `application/json` + +**.format**: `'.json'` + +**.charset**: `None` + +## UnicodeJSONRenderer + +Renders the request data into `JSON`, using utf-8 encoding. + +Note that non-ascii characters will not be character escaped. For example: + + {"unicode black star": "★"} The client may additionally include an `'indent'` media type parameter, in which case the returned `JSON` will be indented. For example `Accept: application/json; indent=4`. + { + "unicode black star": "★" + } + +Both the `JSONRenderer` and `UnicodeJSONRenderer` styles conform to [RFC 4627][rfc4627], and are syntactically valid JSON. + **.media_type**: `application/json` **.format**: `'.json'` +**.charset**: `None` + ## JSONPRenderer Renders the request data into `JSONP`. The `JSONP` media type provides a mechanism of allowing cross-domain AJAX requests, by wrapping a `JSON` response in a javascript callback. The javascript callback function must be set by the client including a `callback` URL query parameter. For example `http://example.com/api/users?callback=jsonpCallback`. If the callback function is not explicitly set by the client it will default to `'callback'`. -**Note**: If you require cross-domain AJAX requests, you may also want to consider using [CORS] as an alternative to `JSONP`. +--- + +**Warning**: If you require cross-domain AJAX requests, you should almost certainly be using the more modern approach of [CORS][cors] as an alternative to `JSONP`. See the [CORS documentation][cors-docs] for more details. + +The `jsonp` approach is essentially a browser hack, and is [only appropriate for globally readable API endpoints][jsonp-security], where `GET` requests are unauthenticated and do not require any user permissions. + +--- **.media_type**: `application/javascript` **.format**: `'.jsonp'` +**.charset**: `utf-8` + ## YAMLRenderer Renders the request data into `YAML`. +Requires the `pyyaml` package to be installed. + **.media_type**: `application/yaml` **.format**: `'.yaml'` +**.charset**: `utf-8` + ## XMLRenderer Renders REST framework's default style of `XML` response content. @@ -106,6 +156,8 @@ If you are considering using `XML` for your API, you may want to consider implem **.format**: `'.xml'` +**.charset**: `utf-8` + ## TemplateHTMLRenderer Renders data to HTML, using Django's standard template rendering. @@ -115,20 +167,20 @@ The TemplateHTMLRenderer will create a `RequestContext`, using the `response.dat The template name is determined by (in order of preference): -1. An explicit `.template_name` attribute set on the response. +1. An explicit `template_name` argument passed to the response. 2. An explicit `.template_name` attribute set on this class. 3. The return result of calling `view.get_template_names()`. An example of a view that uses `TemplateHTMLRenderer`: - class UserInstance(generics.RetrieveUserAPIView): + class UserDetail(generics.RetrieveAPIView): """ A view that returns a templated HTML representations of a given user. """ - model = Users + queryset = User.objects.all() renderer_classes = (TemplateHTMLRenderer,) - def get(self, request, *args, **kwargs) + def get(self, request, *args, **kwargs): self.object = self.get_object() return Response({'user': self.object}, template_name='user_detail.html') @@ -140,6 +192,8 @@ If you're building websites that use `TemplateHTMLRenderer` along with other ren **.format**: `'.html'` +**.charset**: `utf-8` + See also: `StaticHTMLRenderer` ## StaticHTMLRenderer @@ -160,22 +214,62 @@ You can use `TemplateHTMLRenderer` either to return regular HTML pages using RES **.format**: `'.html'` +**.charset**: `utf-8` + See also: `TemplateHTMLRenderer` +## HTMLFormRenderer + +Renders data returned by a serializer into an HTML form. The output of this renderer does not include the enclosing `<form>` tags or an submit actions, as you'll probably need those to include the desired method and URL. Also note that the `HTMLFormRenderer` does not yet support including field error messages. + +Note that the template used by the `HTMLFormRenderer` class, and the context submitted to it **may be subject to change**. If you need to use this renderer class it is advised that you either make a local copy of the class and templates, or follow the release note on REST framework upgrades closely. + +**.media_type**: `text/html` + +**.format**: `'.form'` + +**.charset**: `utf-8` + +**.template**: `'rest_framework/form.html'` + ## BrowsableAPIRenderer -Renders data into HTML for the Browseable API. This renderer will determine which other renderer would have been given highest priority, and use that to display an API style response within the HTML page. +Renders data into HTML for the Browsable API. This renderer will determine which other renderer would have been given highest priority, and use that to display an API style response within the HTML page. **.media_type**: `text/html` **.format**: `'.api'` +**.charset**: `utf-8` + +**.template**: `'rest_framework/api.html'` + +#### Customizing BrowsableAPIRenderer + +By default the response content will be rendered with the highest priority renderer apart from `BrowseableAPIRenderer`. If you need to customize this behavior, for example to use HTML as the default return format, but use JSON in the browsable API, you can do so by overriding the `get_default_renderer()` method. For example: + + class CustomBrowsableAPIRenderer(BrowsableAPIRenderer): + def get_default_renderer(self, view): + return JSONRenderer() + +## MultiPartRenderer + +This renderer is used for rendering HTML multipart form data. **It is not suitable as a response renderer**, but is instead used for creating test requests, using REST framework's [test client and test request factory][testing]. + +**.media_type**: `multipart/form-data; boundary=BoUnDaRyStRiNg` + +**.format**: `'.multipart'` + +**.charset**: `utf-8` + --- # Custom renderers To implement a custom renderer, you should override `BaseRenderer`, set the `.media_type` and `.format` properties, and implement the `.render(self, data, media_type=None, renderer_context=None)` method. +The method should return a bytestring, which will be used as the body of the HTTP response. + The arguments passed to the `.render()` method are: ### `data` @@ -184,13 +278,13 @@ The request data, as set by the `Response()` instantiation. ### `media_type=None` -Optional. If provided, this is the accepted media type, as determined by the content negotiation stage. +Optional. If provided, this is the accepted media type, as determined by the content negotiation stage. Depending on the client's `Accept:` header, this may be more specific than the renderer's `media_type` attribute, and may include media type parameters. For example `"application/json; nested=true"`. ### `renderer_context=None` -Optional. If provided, this is a dictionary of contextual information provided by the view. +Optional. If provided, this is a dictionary of contextual information provided by the view. By default this will include the following keys: `view`, `request`, `response`, `args`, `kwargs`. @@ -202,14 +296,39 @@ The following is an example plaintext renderer that will return a response with from rest_framework import renderers - class PlainText(renderers.BaseRenderer): + class PlainTextRenderer(renderers.BaseRenderer): media_type = 'text/plain' format = 'txt' def render(self, data, media_type=None, renderer_context=None): - if isinstance(data, basestring): - return data - return smart_unicode(data) + return data.encode(self.charset) + +## Setting the character set + +By default renderer classes are assumed to be using the `UTF-8` encoding. To use a different encoding, set the `charset` attribute on the renderer. + + class PlainTextRenderer(renderers.BaseRenderer): + media_type = 'text/plain' + format = 'txt' + charset = 'iso-8859-1' + + def render(self, data, media_type=None, renderer_context=None): + return data.encode(self.charset) + +Note that if a renderer class returns a unicode string, then the response content will be coerced into a bytestring by the `Response` class, with the `charset` attribute set on the renderer used to determine the encoding. + +If the renderer returns a bytestring representing raw binary content, you should set a charset value of `None`, which will ensure the `Content-Type` header of the response will not have a `charset` value set. + +In some cases you may also want to set the `render_style` attribute to `'binary'`. Doing so will also ensure that the browsable API will not attempt to display the binary content as a string. + + class JPEGRenderer(renderers.BaseRenderer): + media_type = 'image/jpeg' + format = 'jpg' + charset = None + render_style = 'binary' + + def render(self, data, media_type=None, renderer_context=None): + return data --- @@ -249,6 +368,15 @@ For example: data = serializer.data return Response(data) +## Underspecifying the media type + +In some cases you might want a renderer to serve a range of media types. +In this case you can underspecify the media types it should respond to, by using a `media_type` value such as `image/*`, or `*/*`. + +If you underspecify the renderer's media type, you should make sure to specify the media type explicitly when you return the response, using the `content_type` attribute. For example: + + return Response(data, content_type='image/png') + ## Designing your media types For the purposes of many Web APIs, simple `JSON` responses with hyperlinked relations may be sufficient. If you want to fully embrace RESTful design and [HATEOAS] you'll need to consider the design and usage of your media types in more detail. @@ -271,13 +399,44 @@ Exceptions raised and handled by an HTML renderer will attempt to render using o Templates will render with a `RequestContext` which includes the `status_code` and `details` keys. +**Note**: If `DEBUG=True`, Django's standard traceback error page will be displayed instead of rendering the HTTP status code and text. + +--- + +# Third party packages + +The following third party packages are also available. + +## MessagePack + +[MessagePack][messagepack] is a fast, efficient binary serialization format. [Juan Riaza][juanriaza] maintains the [djangorestframework-msgpack][djangorestframework-msgpack] package which provides MessagePack renderer and parser support for REST framework. + +## CSV + +Comma-separated values are a plain-text tabular data format, that can be easily imported into spreadsheet applications. [Mjumbe Poe][mjumbewu] maintains the [djangorestframework-csv][djangorestframework-csv] package which provides CSV renderer support for REST framework. + +## UltraJSON + +[UltraJSON][ultrajson] is an optimized C JSON encoder which can give significantly faster JSON rendering. [Jacob Haslehurst][hzy] maintains the [drf-ujson-renderer][drf-ujson-renderer] package which implements JSON rendering using the UJSON package. [cite]: https://docs.djangoproject.com/en/dev/ref/template-response/#the-rendering-process [conneg]: content-negotiation.md [browser-accept-headers]: http://www.gethifi.com/blog/browser-rest-http-accept-headers -[CORS]: http://en.wikipedia.org/wiki/Cross-origin_resource_sharing +[rfc4627]: http://www.ietf.org/rfc/rfc4627.txt +[cors]: http://www.w3.org/TR/cors/ +[cors-docs]: ../topics/ajax-csrf-cors.md +[jsonp-security]: http://stackoverflow.com/questions/613962/is-jsonp-safe-to-use +[testing]: testing.md [HATEOAS]: http://timelessrepo.com/haters-gonna-hateoas [quote]: http://roy.gbiv.com/untangled/2008/rest-apis-must-be-hypertext-driven [application/vnd.github+json]: http://developer.github.com/v3/media/ [application/vnd.collection+json]: http://www.amundsen.com/media-types/collection/ -[django-error-views]: https://docs.djangoproject.com/en/dev/topics/http/views/#customizing-error-views
\ No newline at end of file +[django-error-views]: https://docs.djangoproject.com/en/dev/topics/http/views/#customizing-error-views +[messagepack]: http://msgpack.org/ +[juanriaza]: https://github.com/juanriaza +[mjumbewu]: https://github.com/mjumbewu +[djangorestframework-msgpack]: https://github.com/juanriaza/django-rest-framework-msgpack +[djangorestframework-csv]: https://github.com/mjumbewu/django-rest-framework-csv +[ultrajson]: https://github.com/esnme/ultrajson +[hzy]: https://github.com/hzy +[drf-ujson-renderer]: https://github.com/gizmag/drf-ujson-renderer diff --git a/docs/api-guide/requests.md b/docs/api-guide/requests.md index 72932f5d..0696fedf 100644 --- a/docs/api-guide/requests.md +++ b/docs/api-guide/requests.md @@ -83,13 +83,13 @@ You won't typically need to access this property. # Browser enhancements -REST framework supports a few browser enhancements such as browser-based `PUT` and `DELETE` forms. +REST framework supports a few browser enhancements such as browser-based `PUT`, `PATCH` and `DELETE` forms. ## .method `request.method` returns the **uppercased** string representation of the request's HTTP method. -Browser-based `PUT` and `DELETE` forms are transparently supported. +Browser-based `PUT`, `PATCH` and `DELETE` forms are transparently supported. For more information see the [browser enhancements documentation]. @@ -117,7 +117,7 @@ For more information see the [browser enhancements documentation]. # Standard HttpRequest attributes -As REST framework's `Request` extends Django's `HttpRequest`, all the other standard attributes and methods are also available. For example the `request.META` dictionary is available as normal. +As REST framework's `Request` extends Django's `HttpRequest`, all the other standard attributes and methods are also available. For example the `request.META` and `request.session` dictionaries are available as normal. Note that due to implementation reasons the `Request` class does not inherit from `HttpRequest` class, but instead extends the class using composition. diff --git a/docs/api-guide/responses.md b/docs/api-guide/responses.md index 794f9377..5a42aa92 100644 --- a/docs/api-guide/responses.md +++ b/docs/api-guide/responses.md @@ -2,15 +2,15 @@ # Responses -> Unlike basic HttpResponse objects, TemplateResponse objects retain the details of the context that was provided by the view to compute the response. The final output of the response is not computed until it is needed, later in the response process. +> Unlike basic HttpResponse objects, TemplateResponse objects retain the details of the context that was provided by the view to compute the response. The final output of the response is not computed until it is needed, later in the response process. > > — [Django documentation][cite] REST framework supports HTTP content negotiation by providing a `Response` class which allows you to return content that can be rendered into multiple content types, depending on the client request. -The `Response` class subclasses Django's `SimpleTemplateResponse`. `Response` objects are initialised with data, which should consist of native python primatives. REST framework then uses standard HTTP content negotiation to determine how it should render the final response content. +The `Response` class subclasses Django's `SimpleTemplateResponse`. `Response` objects are initialised with data, which should consist of native Python primitives. REST framework then uses standard HTTP content negotiation to determine how it should render the final response content. -There's no requirement for you to use the `Response` class, you can also return regular `HttpResponse` objects from your views if you want, but it provides a nicer interface for returning Web API responses. +There's no requirement for you to use the `Response` class, you can also return regular `HttpResponse` or `StreamingHttpResponse` objects from your views if required. Using the `Response` class simply provides a nicer interface for returning content-negotiated Web API responses, that can be rendered to multiple formats. Unless you want to heavily customize REST framework for some reason, you should always use an `APIView` class or `@api_view` function for views that return `Response` objects. Doing so ensures that the view can perform content negotiation and select the appropriate renderer for the response, before it is returned from the view. @@ -20,11 +20,11 @@ Unless you want to heavily customize REST framework for some reason, you should ## Response() -**Signature:** `Response(data, status=None, template_name=None, headers=None)` +**Signature:** `Response(data, status=None, template_name=None, headers=None, content_type=None)` -Unlike regular `HttpResponse` objects, you do not instantiate `Response` objects with rendered content. Instead you pass in unrendered data, which may consist of any python primatives. +Unlike regular `HttpResponse` objects, you do not instantiate `Response` objects with rendered content. Instead you pass in unrendered data, which may consist of any Python primitives. -The renderers used by the `Response` class cannot natively handle complex datatypes such as Django model instances, so you need to serialize the data into primative datatypes before creating the `Response` object. +The renderers used by the `Response` class cannot natively handle complex datatypes such as Django model instances, so you need to serialize the data into primitive datatypes before creating the `Response` object. You can use REST framework's `Serializer` classes to perform this data serialization, or use your own custom serialization. @@ -34,6 +34,7 @@ Arguments: * `status`: A status code for the response. Defaults to 200. See also [status codes][statuscodes]. * `template_name`: A template name to use if `HTMLRenderer` is selected. * `headers`: A dictionary of HTTP headers to use in the response. +* `content_type`: The content type of the response. Typically, this will be set automatically by the renderer as determined by content negotiation, but there may be some cases where you need to specify the content type explicitly. --- @@ -53,7 +54,7 @@ The rendered content of the response. The `.render()` method must have been cal ## .template_name -The `template_name`, if supplied. Only required if `HTMLRenderer` or some other custom template renderer is the accepted renderer for the reponse. +The `template_name`, if supplied. Only required if `HTMLRenderer` or some other custom template renderer is the accepted renderer for the response. ## .accepted_renderer diff --git a/docs/api-guide/reverse.md b/docs/api-guide/reverse.md index 19930dc3..383eca4c 100644 --- a/docs/api-guide/reverse.md +++ b/docs/api-guide/reverse.md @@ -17,7 +17,7 @@ The advantages of doing so are: REST framework provides two utility functions to make it more simple to return absolute URIs from your Web API. -There's no requirement for you to use them, but if you do then the self-describing API will be able to automatically hyperlink it's output for you, which makes browsing the API much easier. +There's no requirement for you to use them, but if you do then the self-describing API will be able to automatically hyperlink its output for you, which makes browsing the API much easier. ## reverse @@ -27,13 +27,13 @@ Has the same behavior as [`django.core.urlresolvers.reverse`][reverse], except t You should **include the request as a keyword argument** to the function, for example: - import datetime from rest_framework.reverse import reverse from rest_framework.views import APIView + from django.utils.timezone import now class APIRootView(APIView): def get(self, request): - year = datetime.datetime.now().year + year = now().year data = { ... 'year-summary-url': reverse('year-summary', args=[year], request=request) diff --git a/docs/api-guide/routers.md b/docs/api-guide/routers.md new file mode 100644 index 00000000..fb48197e --- /dev/null +++ b/docs/api-guide/routers.md @@ -0,0 +1,153 @@ +<a class="github" href="routers.py"></a> + +# Routers + +> Resource routing allows you to quickly declare all of the common routes for a given resourceful controller. Instead of declaring separate routes for your index... a resourceful route declares them in a single line of code. +> +> — [Ruby on Rails Documentation][cite] + +Some Web frameworks such as Rails provide functionality for automatically determining how the URLs for an application should be mapped to the logic that deals with handling incoming requests. + +REST framework adds support for automatic URL routing to Django, and provides you with a simple, quick and consistent way of wiring your view logic to a set of URLs. + +## Usage + +Here's an example of a simple URL conf, that uses `DefaultRouter`. + + from rest_framework import routers + + router = routers.SimpleRouter() + router.register(r'users', UserViewSet) + router.register(r'accounts', AccountViewSet) + urlpatterns = router.urls + +There are two mandatory arguments to the `register()` method: + +* `prefix` - The URL prefix to use for this set of routes. +* `viewset` - The viewset class. + +Optionally, you may also specify an additional argument: + +* `base_name` - The base to use for the URL names that are created. If unset the basename will be automatically generated based on the `model` or `queryset` attribute on the viewset, if it has one. Note that if the viewset does not include a `model` or `queryset` attribute then you must set `base_name` when registering the viewset. + +The example above would generate the following URL patterns: + +* URL pattern: `^users/$` Name: `'user-list'` +* URL pattern: `^users/{pk}/$` Name: `'user-detail'` +* URL pattern: `^accounts/$` Name: `'account-list'` +* URL pattern: `^accounts/{pk}/$` Name: `'account-detail'` + +### Extra link and actions + +Any methods on the viewset decorated with `@link` or `@action` will also be routed. +For example, given a method like this on the `UserViewSet` class: + + from myapp.permissions import IsAdminOrIsSelf + from rest_framework.decorators import action + + @action(permission_classes=[IsAdminOrIsSelf]) + def set_password(self, request, pk=None): + ... + +The following URL pattern would additionally be generated: + +* URL pattern: `^users/{pk}/set_password/$` Name: `'user-set-password'` + +# API Guide + +## SimpleRouter + +This router includes routes for the standard set of `list`, `create`, `retrieve`, `update`, `partial_update` and `destroy` actions. The viewset can also mark additional methods to be routed, using the `@link` or `@action` decorators. + +<table border=1> + <tr><th>URL Style</th><th>HTTP Method</th><th>Action</th><th>URL Name</th></tr> + <tr><td rowspan=2>{prefix}/</td><td>GET</td><td>list</td><td rowspan=2>{basename}-list</td></tr></tr> + <tr><td>POST</td><td>create</td></tr> + <tr><td rowspan=4>{prefix}/{lookup}/</td><td>GET</td><td>retrieve</td><td rowspan=4>{basename}-detail</td></tr></tr> + <tr><td>PUT</td><td>update</td></tr> + <tr><td>PATCH</td><td>partial_update</td></tr> + <tr><td>DELETE</td><td>destroy</td></tr> + <tr><td rowspan=2>{prefix}/{lookup}/{methodname}/</td><td>GET</td><td>@link decorated method</td><td rowspan=2>{basename}-{methodname}</td></tr> + <tr><td>POST</td><td>@action decorated method</td></tr> +</table> + +By default the URLs created by `SimpleRouter` are appended with a trailing slash. +This behavior can be modified by setting the `trailing_slash` argument to `False` when instantiating the router. For example: + + router = SimpleRouter(trailing_slash=False) + +Trailing slashes are conventional in Django, but are not used by default in some other frameworks such as Rails. Which style you choose to use is largely a matter of preference, although some javascript frameworks may expect a particular routing style. + +## DefaultRouter + +This router is similar to `SimpleRouter` as above, but additionally includes a default API root view, that returns a response containing hyperlinks to all the list views. It also generates routes for optional `.json` style format suffixes. + +<table border=1> + <tr><th>URL Style</th><th>HTTP Method</th><th>Action</th><th>URL Name</th></tr> + <tr><td>[.format]</td><td>GET</td><td>automatically generated root view</td><td>api-root</td></tr></tr> + <tr><td rowspan=2>{prefix}/[.format]</td><td>GET</td><td>list</td><td rowspan=2>{basename}-list</td></tr></tr> + <tr><td>POST</td><td>create</td></tr> + <tr><td rowspan=4>{prefix}/{lookup}/[.format]</td><td>GET</td><td>retrieve</td><td rowspan=4>{basename}-detail</td></tr></tr> + <tr><td>PUT</td><td>update</td></tr> + <tr><td>PATCH</td><td>partial_update</td></tr> + <tr><td>DELETE</td><td>destroy</td></tr> + <tr><td rowspan=2>{prefix}/{lookup}/{methodname}/[.format]</td><td>GET</td><td>@link decorated method</td><td rowspan=2>{basename}-{methodname}</td></tr> + <tr><td>POST</td><td>@action decorated method</td></tr> +</table> + +As with `SimpleRouter` the trailing slashes on the URL routes can be removed by setting the `trailing_slash` argument to `False` when instantiating the router. + + router = DefaultRouter(trailing_slash=False) + +# Custom Routers + +Implementing a custom router isn't something you'd need to do very often, but it can be useful if you have specific requirements about how the your URLs for your API are structured. Doing so allows you to encapsulate the URL structure in a reusable way that ensures you don't have to write your URL patterns explicitly for each new view. + +The simplest way to implement a custom router is to subclass one of the existing router classes. The `.routes` attribute is used to template the URL patterns that will be mapped to each viewset. The `.routes` attribute is a list of `Route` named tuples. + +The arguments to the `Route` named tuple are: + +**url**: A string representing the URL to be routed. May include the following format strings: + +* `{prefix}` - The URL prefix to use for this set of routes. +* `{lookup}` - The lookup field used to match against a single instance. +* `{trailing_slash}` - Either a '/' or an empty string, depending on the `trailing_slash` argument. + +**mapping**: A mapping of HTTP method names to the view methods + +**name**: The name of the URL as used in `reverse` calls. May include the following format string: + +* `{basename}` - The base to use for the URL names that are created. + +**initkwargs**: A dictionary of any additional arguments that should be passed when instantiating the view. Note that the `suffix` argument is reserved for identifying the viewset type, used when generating the view name and breadcrumb links. + +## Example + +The following example will only route to the `list` and `retrieve` actions, and does not use the trailing slash convention. + + from rest_framework.routers import Route, SimpleRouter + + class ReadOnlyRouter(SimpleRouter): + """ + A router for read-only APIs, which doesn't use trailing slashes. + """ + routes = [ + Route(url=r'^{prefix}$', + mapping={'get': 'list'}, + name='{basename}-list', + initkwargs={'suffix': 'List'}), + Route(url=r'^{prefix}/{lookup}$', + mapping={'get': 'retrieve'}, + name='{basename}-detail', + initkwargs={'suffix': 'Detail'}) + ] + +The `SimpleRouter` class provides another example of setting the `.routes` attribute. + +## Advanced custom routers + +If you want to provide totally custom behavior, you can override `BaseRouter` and override the `get_urls(self)` method. The method should inspect the registered viewsets and return a list of URL patterns. The registered prefix, viewset and basename tuples may be inspected by accessing the `self.registry` attribute. + +You may also want to override the `get_default_base_name(self, viewset)` method, or else always explicitly set the `base_name` argument when registering your viewsets with the router. + +[cite]: http://guides.rubyonrails.org/routing.html diff --git a/docs/api-guide/serializers.md b/docs/api-guide/serializers.md index a9589144..4c3fb9d3 100644 --- a/docs/api-guide/serializers.md +++ b/docs/api-guide/serializers.md @@ -3,13 +3,12 @@ # Serializers > Expanding the usefulness of the serializers is something that we would -like to address. However, it's not a trivial problem, and it -will take some serious design work. Any offers to help out in this -area would be gratefully accepted. +like to address. However, it's not a trivial problem, and it +will take some serious design work. > > — Russell Keith-Magee, [Django users group][cite] -Serializers allow complex data such as querysets and model instances to be converted to native python datatypes that can then be easily rendered into `JSON`, `XML` or other content types. Serializers also provide deserialization, allowing parsed data to be converted back into complex types, after first validating the incoming data. +Serializers allow complex data such as querysets and model instances to be converted to native Python datatypes that can then be easily rendered into `JSON`, `XML` or other content types. Serializers also provide deserialization, allowing parsed data to be converted back into complex types, after first validating the incoming data. REST framework's serializers work very similarly to Django's `Form` and `ModelForm` classes. It provides a `Serializer` class which gives you a powerful, generic way to control the output of your responses, as well as a `ModelSerializer` class which provides a useful shortcut for creating serializers that deal with model instances and querysets. @@ -26,22 +25,31 @@ Let's start by creating a simple object we can use for example purposes: comment = Comment(email='leila@example.com', content='foo bar') We'll declare a serializer that we can use to serialize and deserialize `Comment` objects. + Declaring a serializer looks very similar to declaring a form: + from rest_framework import serializers + class CommentSerializer(serializers.Serializer): email = serializers.EmailField() content = serializers.CharField(max_length=200) created = serializers.DateTimeField() def restore_object(self, attrs, instance=None): - if instance: - instance.title = attrs['title'] - instance.content = attrs['content'] - instance.created = attrs['created'] + """ + Given a dictionary of deserialized field values, either update + an existing model instance, or create a new model instance. + """ + if instance is not None: + instance.email = attrs.get('email', instance.email) + instance.content = attrs.get('content', instance.content) + instance.created = attrs.get('created', instance.created) return instance return Comment(**attrs) -The first part of serializer class defines the fields that get serialized/deserialized. The `restore_object` method defines how fully fledged instances get created when deserializing data. The `restore_object` method is optional, and is only required if we want our serializer to support deserialization. +The first part of serializer class defines the fields that get serialized/deserialized. The `restore_object` method defines how fully fledged instances get created when deserializing data. + +The `restore_object` method is optional, and is only required if we want our serializer to support deserialization into fully fledged object instances. If we don't define this method, then deserializing data will simply return a dictionary of items. ## Serializing objects @@ -51,16 +59,37 @@ We can now use `CommentSerializer` to serialize a comment, or list of comments. serializer.data # {'email': u'leila@example.com', 'content': u'foo bar', 'created': datetime.datetime(2012, 8, 22, 16, 20, 9, 822774)} -At this point we've translated the model instance into python native datatypes. To finalise the serialization process we render the data into `json`. +At this point we've translated the model instance into Python native datatypes. To finalise the serialization process we render the data into `json`. + + from rest_framework.renderers import JSONRenderer - stream = JSONRenderer().render(data) - stream + json = JSONRenderer().render(serializer.data) + json # '{"email": "leila@example.com", "content": "foo bar", "created": "2012-08-22T16:20:09.822"}' +### Customizing field representation + +Sometimes when serializing objects, you may not want to represent everything exactly the way it is in your model. + +If you need to customize the serialized value of a particular field, you can do this by creating a `transform_<fieldname>` method. For example if you needed to render some markdown from a text field: + + description = serializers.TextField() + description_html = serializers.TextField(source='description', read_only=True) + + def transform_description_html(self, obj, value): + from django.contrib.markup.templatetags.markup import markdown + return markdown(value) + +These methods are essentially the reverse of `validate_<fieldname>` (see *Validation* below.) + ## Deserializing objects -Deserialization is similar. First we parse a stream into python native datatypes... +Deserialization is similar. First we parse a stream into Python native datatypes... + from StringIO import StringIO + from rest_framework.parsers import JSONParser + + stream = StringIO(json) data = JSONParser().parse(stream) ...then we restore those native datatypes into a fully populated object instance. @@ -70,24 +99,37 @@ Deserialization is similar. First we parse a stream into python native datatype # True serializer.object # <Comment object at 0x10633b2d0> - >>> serializer.deserialize('json', stream) When deserializing data, we can either create a new instance, or update an existing instance. serializer = CommentSerializer(data=data) # Create new instance serializer = CommentSerializer(comment, data=data) # Update `instance` +By default, serializers must be passed values for all required fields or they will throw validation errors. You can use the `partial` argument in order to allow partial updates. + + serializer = CommentSerializer(comment, data={'content': u'foo bar'}, partial=True) # Update `instance` with partial data + ## Validation -When deserializing data, you always need to call `is_valid()` before attempting to access the deserialized object. If any validation errors occur, the `.errors` and `.non_field_errors` properties will contain the resulting error messages. +When deserializing data, you always need to call `is_valid()` before attempting to access the deserialized object. If any validation errors occur, the `.errors` property will contain a dictionary representing the resulting error messages. For example: + + serializer = CommentSerializer(data={'email': 'foobar', 'content': 'baz'}) + serializer.is_valid() + # False + serializer.errors + # {'email': [u'Enter a valid e-mail address.'], 'created': [u'This field is required.']} + +Each key in the dictionary will be the field name, and the values will be lists of strings of any error messages corresponding to that field. The `non_field_errors` key may also be present, and will list any general validation errors. -### Field-level validation +When deserializing a list of items, errors will be returned as a list of dictionaries representing each of the deserialized items. -You can specify custom field-level validation by adding `.validate_<fieldname>` methods to your `Serializer` subclass. These are analagous to `.clean_<fieldname>` methods on Django forms, but accept slightly different arguments. +#### Field-level validation + +You can specify custom field-level validation by adding `.validate_<fieldname>` methods to your `Serializer` subclass. These are analogous to `.clean_<fieldname>` methods on Django forms, but accept slightly different arguments. They take a dictionary of deserialized attributes as a first argument, and the field name in that dictionary as a second argument (which will be either the name of the field or the value of the `source` argument to the field, if one was provided). -Your `validate_<fieldname>` methods should either just return the `attrs` dictionary or raise a `ValidationError`. For example: +Your `validate_<fieldname>` methods should either just return the `attrs` dictionary or raise a `ValidationError`. For example: from rest_framework import serializers @@ -104,90 +146,178 @@ Your `validate_<fieldname>` methods should either just return the `attrs` dictio raise serializers.ValidationError("Blog post is not about Django") return attrs -### Object-level validation +#### Object-level validation + +To do any other validation that requires access to multiple fields, add a method called `.validate()` to your `Serializer` subclass. This method takes a single argument, which is the `attrs` dictionary. It should raise a `ValidationError` if necessary, or just return `attrs`. For example: -To do any other validation that requires access to multiple fields, add a method called `.validate()` to your `Serializer` subclass. This method takes a single argument, which is the `attrs` dictionary. It should raise a `ValidationError` if necessary, or just return `attrs`. + from rest_framework import serializers + + class EventSerializer(serializers.Serializer): + description = serializers.CharField(max_length=100) + start = serializers.DateTimeField() + finish = serializers.DateTimeField() + + def validate(self, attrs): + """ + Check that the start is before the stop. + """ + if attrs['start'] < attrs['finish']: + raise serializers.ValidationError("finish must occur after start") + return attrs ## Saving object state -Serializers also include a `.save()` method that you can override if you want to provide a method of persisting the state of a deserialized object. The default behavior of the method is to simply call `.save()` on the deserialized object instance. +To save the deserialized objects created by a serializer, call the `.save()` method: + + if serializer.is_valid(): + serializer.save() + +The default behavior of the method is to simply call `.save()` on the deserialized object instance. You can override the default save behaviour by overriding the `.save_object(obj)` method on the serializer class. The generic views provided by REST framework call the `.save()` method when updating or creating entities. ## Dealing with nested objects -The previous example is fine for dealing with objects that only have simple datatypes, but sometimes we also need to be able to represent more complex objects, -where some of the attributes of an object might not be simple datatypes such as strings, dates or integers. +The previous examples are fine for dealing with objects that only have simple datatypes, but sometimes we also need to be able to represent more complex objects, where some of the attributes of an object might not be simple datatypes such as strings, dates or integers. The `Serializer` class is itself a type of `Field`, and can be used to represent relationships where one object type is nested inside another. class UserSerializer(serializers.Serializer): - email = serializers.Field() - username = serializers.Field() + email = serializers.EmailField() + username = serializers.CharField(max_length=100) class CommentSerializer(serializers.Serializer): user = UserSerializer() - title = serializers.Field() - content = serializers.Field() - created = serializers.Field() + content = serializers.CharField(max_length=200) + created = serializers.DateTimeField() ---- +If a nested representation may optionally accept the `None` value you should pass the `required=False` flag to the nested serializer. -**Note**: Nested serializers are only suitable for read-only representations, as there are cases where they would have ambiguous or non-obvious behavior if used when updating instances. For read-write representations you should always use a flat representation, by using one of the `RelatedField` subclasses. + class CommentSerializer(serializers.Serializer): + user = UserSerializer(required=False) # May be an anonymous user. + content = serializers.CharField(max_length=200) + created = serializers.DateTimeField() ---- +Similarly if a nested representation should be a list of items, you should pass the `many=True` flag to the nested serialized. + class CommentSerializer(serializers.Serializer): + user = UserSerializer(required=False) + edits = EditItemSerializer(many=True) # A nested list of 'edit' items. + content = serializers.CharField(max_length=200) + created = serializers.DateTimeField() -## Creating custom fields +Validation of nested objects will work the same as before. Errors with nested objects will be nested under the field name of the nested object. -If you want to create a custom field, you'll probably want to override either one or both of the `.to_native()` and `.from_native()` methods. These two methods are used to convert between the intial datatype, and a primative, serializable datatype. Primative datatypes may be any of a number, string, date/time/datetime or None. They may also be any list or dictionary like object that only contains other primative objects. + serializer = CommentSerializer(comment, data={'user': {'email': 'foobar', 'username': 'doe'}, 'content': 'baz'}) + serializer.is_valid() + # False + serializer.errors + # {'user': {'email': [u'Enter a valid e-mail address.']}, 'created': [u'This field is required.']} -The `.to_native()` method is called to convert the initial datatype into a primative, serializable datatype. The `from_native()` method is called to restore a primative datatype into it's initial representation. +## Dealing with multiple objects -Let's look at an example of serializing a class that represents an RGB color value: +The `Serializer` class can also handle serializing or deserializing lists of objects. - class Color(object): - """ - A color represented in the RGB colorspace. - """ - def __init__(self, red, green, blue): - assert(red >= 0 and green >= 0 and blue >= 0) - assert(red < 256 and green < 256 and blue < 256) - self.red, self.green, self.blue = red, green, blue +#### Serializing multiple objects - class ColourField(serializers.WritableField): - """ - Color objects are serialized into "rgb(#, #, #)" notation. - """ - def to_native(self, obj): - return "rgb(%d, %d, %d)" % (obj.red, obj.green, obj.blue) - - def from_native(self, data): - data = data.strip('rgb(').rstrip(')') - red, green, blue = [int(col) for col in data.split(',')] - return Color(red, green, blue) - +To serialize a queryset or list of objects instead of a single object instance, you should pass the `many=True` flag when instantiating the serializer. You can then pass a queryset or list of objects to be serialized. -By default field values are treated as mapping to an attribute on the object. If you need to customize how the field value is accessed and set you need to override `.field_to_native()` and/or `.field_from_native()`. + queryset = Book.objects.all() + serializer = BookSerializer(queryset, many=True) + serializer.data + # [ + # {'id': 0, 'title': 'The electric kool-aid acid test', 'author': 'Tom Wolfe'}, + # {'id': 1, 'title': 'If this is a man', 'author': 'Primo Levi'}, + # {'id': 2, 'title': 'The wind-up bird chronicle', 'author': 'Haruki Murakami'} + # ] -As an example, let's create a field that can be used represent the class name of the object being serialized: +#### Deserializing multiple objects for creation - class ClassNameField(serializers.WritableField): - def field_to_native(self, obj, field_name): - """ - Serialize the object's class name, not an attribute of the object. - """ - return obj.__class__.__name__ +To deserialize a list of object data, and create multiple object instances in a single pass, you should also set the `many=True` flag, and pass a list of data to be deserialized. + +This allows you to write views that create multiple items when a `POST` request is made. + +For example: + + data = [ + {'title': 'The bell jar', 'author': 'Sylvia Plath'}, + {'title': 'For whom the bell tolls', 'author': 'Ernest Hemingway'} + ] + serializer = BookSerializer(data=data, many=True) + serializer.is_valid() + # True + serializer.save() # `.save()` will be called on each deserialized instance - def field_from_native(self, data, field_name, into): +#### Deserializing multiple objects for update + +You can also deserialize a list of objects as part of a bulk update of multiple existing items. +In this case you need to supply both an existing list or queryset of items, as well as a list of data to update those items with. + +This allows you to write views that update or create multiple items when a `PUT` request is made. + + # Capitalizing the titles of the books + queryset = Book.objects.all() + data = [ + {'id': 3, 'title': 'The Bell Jar', 'author': 'Sylvia Plath'}, + {'id': 4, 'title': 'For Whom the Bell Tolls', 'author': 'Ernest Hemingway'} + ] + serializer = BookSerializer(queryset, data=data, many=True) + serializer.is_valid() + # True + serializer.save() # `.save()` will be called on each updated or newly created instance. + +By default bulk updates will be limited to updating instances that already exist in the provided queryset. + +When performing a bulk update you may want to allow new items to be created, and missing items to be deleted. To do so, pass `allow_add_remove=True` to the serializer. + + serializer = BookSerializer(queryset, data=data, many=True, allow_add_remove=True) + serializer.is_valid() + # True + serializer.save() # `.save()` will be called on updated or newly created instances. + # `.delete()` will be called on any other items in the `queryset`. + +Passing `allow_add_remove=True` ensures that any update operations will completely overwrite the existing queryset, rather than simply updating existing objects. + +#### How identity is determined when performing bulk updates + +Performing a bulk update is slightly more complicated than performing a bulk creation, because the serializer needs a way to determine how the items in the incoming data should be matched against the existing object instances. + +By default the serializer class will use the `id` key on the incoming data to determine the canonical identity of an object. If you need to change this behavior you should override the `get_identity` method on the `Serializer` class. For example: + + class AccountSerializer(serializers.Serializer): + slug = serializers.CharField(max_length=100) + created = serializers.DateTimeField() + ... # Various other fields + + def get_identity(self, data): """ - We don't want to set anything when we revert this field. + This hook is required for bulk update. + We need to override the default, to use the slug as the identity. + + Note that the data has not yet been validated at this point, + so we need to deal gracefully with incorrect datatypes. """ - pass + try: + return data.get('slug', None) + except AttributeError: + return None ---- +To map the incoming data items to their corresponding object instances, the `.get_identity()` method will be called both against the incoming data, and against the serialized representation of the existing objects. + +## Including extra context + +There are some cases where you need to provide extra context to the serializer in addition to the object being serialized. One common case is if you're using a serializer that includes hyperlinked relations, which requires the serializer to have access to the current request so that it can properly generate fully qualified URLs. + +You can provide arbitrary additional context by passing a `context` argument when instantiating the serializer. For example: + + serializer = AccountSerializer(account, context={'request': request}) + serializer.data + # {'id': 6, 'owner': u'denvercoder9', 'created': datetime.datetime(2013, 2, 12, 09, 44, 56, 678870), 'details': 'http://example.com/accounts/6/details'} + +The context dictionary can be used within any serializer field logic, such as a custom `.to_native()` method, by accessing the `self.context` attribute. -# ModelSerializers +- +# ModelSerializer Often you'll want serializer classes that map closely to model definitions. The `ModelSerializer` class lets you automatically create a Serializer class with fields that correspond to the Model fields. @@ -196,15 +326,60 @@ The `ModelSerializer` class lets you automatically create a Serializer class wit class Meta: model = Account -**[TODO: Explain model field to serializer field mapping in more detail]** +By default, all the model fields on the class will be mapped to corresponding serializer fields. + +Any relationships such as foreign keys on the model will be mapped to `PrimaryKeyRelatedField`. Other models fields will be mapped to a corresponding serializer field. + +--- + +**Note**: When validation is applied to a `ModelSerializer`, both the serializer fields, and their corresponding model fields must correctly validate. If you have optional fields on your model, make sure to correctly set `blank=True` on the model field, as well as setting `required=False` on the serializer field. + +--- + +## Specifying which fields should be included + +If you only want a subset of the default fields to be used in a model serializer, you can do so using `fields` or `exclude` options, just as you would with a `ModelForm`. + +For example: + + class AccountSerializer(serializers.ModelSerializer): + class Meta: + model = Account + fields = ('id', 'account_name', 'users', 'created') + +## Specifying nested serialization + +The default `ModelSerializer` uses primary keys for relationships, but you can also easily generate nested representations using the `depth` option: + + class AccountSerializer(serializers.ModelSerializer): + class Meta: + model = Account + fields = ('id', 'account_name', 'users', 'created') + depth = 1 + +The `depth` option should be set to an integer value that indicates the depth of relationships that should be traversed before reverting to a flat representation. + +If you want to customize the way the serialization is done (e.g. using `allow_add_remove`) you'll need to define the field yourself. + +## Specifying which fields should be read-only + +You may wish to specify multiple fields as read-only. Instead of adding each field explicitly with the `read_only=True` attribute, you may use the `read_only_fields` Meta option, like so: + + class AccountSerializer(serializers.ModelSerializer): + class Meta: + model = Account + fields = ('id', 'account_name', 'users', 'created') + read_only_fields = ('account_name',) + +Model fields which have `editable=False` set, and `AutoField` fields will be set to read-only by default, and do not need to be added to the `read_only_fields` option. ## Specifying fields explicitly You can add extra fields to a `ModelSerializer` or override the default fields by declaring fields on the class, just as you would for a `Serializer` class. class AccountSerializer(serializers.ModelSerializer): - url = CharField(source='get_absolute_url', read_only=True) - group = NaturalKeyField() + url = serializers.CharField(source='get_absolute_url', read_only=True) + groups = serializers.PrimaryKeyRelatedField(many=True) class Meta: model = Account @@ -213,55 +388,119 @@ Extra fields can correspond to any property or callable on the model. ## Relational fields -When serializing model instances, there are a number of different ways you might choose to represent relationships. The default representation is to use the primary keys of the related instances. +When serializing model instances, there are a number of different ways you might choose to represent relationships. The default representation for `ModelSerializer` is to use the primary keys of the related instances. -Alternative representations include serializing using natural keys, serializing complete nested representations, or serializing using a custom representation, such as a URL that uniquely identifies the model instances. +Alternative representations include serializing using hyperlinks, serializing complete nested representations, or serializing with a custom representation. -The `PrimaryKeyRelatedField` and `HyperlinkedRelatedField` fields provide alternative flat representations. +For full details see the [serializer relations][relations] documentation. -The `ModelSerializer` class can itself be used as a field, in order to serialize relationships using nested representations. +--- -The `RelatedField` class may be subclassed to create a custom representation of a relationship. The subclass should override `.to_native()`, and optionally `.from_native()` if deserialization is supported. +# HyperlinkedModelSerializer -All the relational fields may be used for any relationship or reverse relationship on a model. +The `HyperlinkedModelSerializer` class is similar to the `ModelSerializer` class except that it uses hyperlinks to represent relationships, rather than primary keys. -## Specifying which fields should be included +By default the serializer will include a `url` field instead of a primary key field. -If you only want a subset of the default fields to be used in a model serializer, you can do so using `fields` or `exclude` options, just as you would with a `ModelForm`. +The url field will be represented using a `HyperlinkedIdentityField` serializer field, and any relationships on the model will be represented using a `HyperlinkedRelatedField` serializer field. -For example: +You can explicitly include the primary key by adding it to the `fields` option, for example: - class AccountSerializer(serializers.ModelSerializer): + class AccountSerializer(serializers.HyperlinkedModelSerializer): class Meta: model = Account - exclude = ('id',) + fields = ('url', 'id', 'account_name', 'users', 'created') -## Specifiying nested serialization +## How hyperlinked views are determined -The default `ModelSerializer` uses primary keys for relationships, but you can also easily generate nested representations using the `depth` option: +There needs to be a way of determining which views should be used for hyperlinking to model instances. - class AccountSerializer(serializers.ModelSerializer): +By default hyperlinks are expected to correspond to a view name that matches the style `'{model_name}-detail'`, and looks up the instance by a `pk` keyword argument. + +You can change the field that is used for object lookups by setting the `lookup_field` option. The value of this option should correspond both with a kwarg in the URL conf, and with a field on the model. For example: + + class AccountSerializer(serializers.HyperlinkedModelSerializer): class Meta: model = Account - exclude = ('id',) - depth = 1 + fields = ('url', 'account_name', 'users', 'created') + lookup_field = 'slug' -The `depth` option should be set to an integer value that indicates the depth of relationships that should be traversed before reverting to a flat representation. +Not that the `lookup_field` will be used as the default on *all* hyperlinked fields, including both the URL identity, and any hyperlinked relationships. -## Specifying which fields should be read-only +For more specific requirements such as specifying a different lookup for each field, you'll want to set the fields on the serializer explicitly. For example: -You may wish to specify multiple fields as read-only. Instead of adding each field explicitely with the `read_only=True` attribute, you may use the `read_only_fields` Meta option, like so: + class AccountSerializer(serializers.HyperlinkedModelSerializer): + url = serializers.HyperlinkedIdentityField( + view_name='account_detail', + lookup_field='account_name' + ) + users = serializers.HyperlinkedRelatedField( + view_name='user-detail', + lookup_field='username', + many=True, + read_only=True + ) - class AccountSerializer(serializers.ModelSerializer): class Meta: model = Account - read_only_fields = ('created', 'modified') + fields = ('url', 'account_name', 'users', 'created') + +--- + +# Advanced serializer usage + +You can create customized subclasses of `ModelSerializer` or `HyperlinkedModelSerializer` that use a different set of default fields. + +Doing so should be considered advanced usage, and will only be needed if you have some particular serializer requirements that you often need to repeat. + +## Dynamically modifying fields + +Once a serializer has been initialized, the dictionary of fields that are set on the serializer may be accessed using the `.fields` attribute. Accessing and modifying this attribute allows you to dynamically modify the serializer. + +Modifying the `fields` argument directly allows you to do interesting things such as changing the arguments on serializer fields at runtime, rather than at the point of declaring the serializer. + +### Example + +For example, if you wanted to be able to set which fields should be used by a serializer at the point of initializing it, you could create a serializer class like so: + + class DynamicFieldsModelSerializer(serializers.ModelSerializer): + """ + A ModelSerializer that takes an additional `fields` argument that + controls which fields should be displayed. + """ + + def __init__(self, *args, **kwargs): + # Don't pass the 'fields' arg up to the superclass + fields = kwargs.pop('fields', None) + + # Instantiate the superclass normally + super(DynamicFieldsModelSerializer, self).__init__(*args, **kwargs) + + if fields: + # Drop any fields that are not specified in the `fields` argument. + allowed = set(fields) + existing = set(self.fields.keys()) + for field_name in existing - allowed: + self.fields.pop(field_name) + +This would then allow you to do the following: + + >>> class UserSerializer(DynamicFieldsModelSerializer): + >>> class Meta: + >>> model = User + >>> fields = ('id', 'username', 'email') + >>> + >>> print UserSerializer(user) + {'id': 2, 'username': 'jonwatts', 'email': 'jon@example.com'} + >>> + >>> print UserSerializer(user, fields=('id', 'email')) + {'id': 2, 'email': 'jon@example.com'} ## Customising the default fields -You can create customized subclasses of `ModelSerializer` that use a different set of default fields for the representation, by overriding various `get_<field_type>_field` methods. +The `field_mapping` attribute is a dictionary that maps model classes to serializer classes. Overriding the attribute will let you set a different set of default serializer classes. -Each of these methods may either return a field or serializer instance, or `None`. +For more advanced customization than simply changing the default serializer class you can override various `get_<field_type>_field` methods. Doing so will allow you to customize the arguments that each serializer field is initialized with. Each of these methods may either return a field or serializer instance, or `None`. ### get_pk_field @@ -271,23 +510,27 @@ Returns the field instance that should be used to represent the pk field. ### get_nested_field -**Signature**: `.get_nested_field(self, model_field)` +**Signature**: `.get_nested_field(self, model_field, related_model, to_many)` Returns the field instance that should be used to represent a related field when `depth` is specified as being non-zero. +Note that the `model_field` argument will be `None` for reverse relationships. The `related_model` argument will be the model class for the target of the field. The `to_many` argument will be a boolean indicating if this is a to-one or to-many relationship. + ### get_related_field -**Signature**: `.get_related_field(self, model_field, to_many=False)` +**Signature**: `.get_related_field(self, model_field, related_model, to_many)` Returns the field instance that should be used to represent a related field when `depth` is not specified, or when nested representations are being used and the depth reaches zero. +Note that the `model_field` argument will be `None` for reverse relationships. The `related_model` argument will be the model class for the target of the field. The `to_many` argument will be a boolean indicating if this is a to-one or to-many relationship. + ### get_field **Signature**: `.get_field(self, model_field)` Returns the field instance that should be used for non-relational, non-pk fields. -### Example: +### Example The following custom model serializer could be used as a base class for model serializers that should always exclude the pk by default. @@ -298,3 +541,4 @@ The following custom model serializer could be used as a base class for model se [cite]: https://groups.google.com/d/topic/django-users/sVFaOfQi4wY/discussion +[relations]: relations.md diff --git a/docs/api-guide/settings.md b/docs/api-guide/settings.md index 7884d096..13f96f9a 100644 --- a/docs/api-guide/settings.md +++ b/docs/api-guide/settings.md @@ -25,16 +25,20 @@ If you need to access the values of REST framework's API settings in your projec you should use the `api_settings` object. For example. from rest_framework.settings import api_settings - + print api_settings.DEFAULT_AUTHENTICATION_CLASSES -The `api_settings` object will check for any user-defined settings, and otherwise fallback to the default values. Any setting that uses string import paths to refer to a class will automatically import and return the referenced class, instead of the string literal. +The `api_settings` object will check for any user-defined settings, and otherwise fall back to the default values. Any setting that uses string import paths to refer to a class will automatically import and return the referenced class, instead of the string literal. --- # API Reference -## DEFAULT_RENDERER_CLASSES +## API policy settings + +*The following settings control the basic API policies, and are applied to every `APIView` class based view, or `@api_view` function based view.* + +#### DEFAULT_RENDERER_CLASSES A list or tuple of renderer classes, that determines the default set of renderers that may be used when returning a `Response` object. @@ -43,10 +47,9 @@ Default: ( 'rest_framework.renderers.JSONRenderer', 'rest_framework.renderers.BrowsableAPIRenderer', - 'rest_framework.renderers.TemplateHTMLRenderer' ) -## DEFAULT_PARSER_CLASSES +#### DEFAULT_PARSER_CLASSES A list or tuple of parser classes, that determines the default set of parsers used when accessing the `request.DATA` property. @@ -54,10 +57,11 @@ Default: ( 'rest_framework.parsers.JSONParser', - 'rest_framework.parsers.FormParser' + 'rest_framework.parsers.FormParser', + 'rest_framework.parsers.MultiPartParser' ) -## DEFAULT_AUTHENTICATION_CLASSES +#### DEFAULT_AUTHENTICATION_CLASSES A list or tuple of authentication classes, that determines the default set of authenticators used when accessing the `request.user` or `request.auth` properties. @@ -65,10 +69,10 @@ Default: ( 'rest_framework.authentication.SessionAuthentication', - 'rest_framework.authentication.UserBasicAuthentication' + 'rest_framework.authentication.BasicAuthentication' ) -## DEFAULT_PERMISSION_CLASSES +#### DEFAULT_PERMISSION_CLASSES A list or tuple of permission classes, that determines the default set of permissions checked at the start of a view. @@ -78,53 +82,134 @@ Default: 'rest_framework.permissions.AllowAny', ) -## DEFAULT_THROTTLE_CLASSES +#### DEFAULT_THROTTLE_CLASSES A list or tuple of throttle classes, that determines the default set of throttles checked at the start of a view. Default: `()` -## DEFAULT_MODEL_SERIALIZER_CLASS +#### DEFAULT_CONTENT_NEGOTIATION_CLASS + +A content negotiation class, that determines how a renderer is selected for the response, given an incoming request. + +Default: `'rest_framework.negotiation.DefaultContentNegotiation'` + +--- + +## Generic view settings + +*The following settings control the behavior of the generic class based views.* -**TODO** +#### DEFAULT_MODEL_SERIALIZER_CLASS -Default: `rest_framework.serializers.ModelSerializer` +A class that determines the default type of model serializer that should be used by a generic view if `model` is specified, but `serializer_class` is not provided. -## DEFAULT_PAGINATION_SERIALIZER_CLASS +Default: `'rest_framework.serializers.ModelSerializer'` -**TODO** +#### DEFAULT_PAGINATION_SERIALIZER_CLASS + +A class the determines the default serialization style for paginated responses. Default: `rest_framework.pagination.PaginationSerializer` -## FILTER_BACKEND +#### DEFAULT_FILTER_BACKENDS -The filter backend class that should be used for generic filtering. If set to `None` then generic filtering is disabled. +A list of filter backend classes that should be used for generic filtering. +If set to `None` then generic filtering is disabled. -## PAGINATE_BY +#### PAGINATE_BY The default page size to use for pagination. If set to `None`, pagination is disabled by default. Default: `None` -## PAGINATE_BY_KWARG +#### PAGINATE_BY_PARAM + +The name of a query parameter, which can be used by the client to override the default page size to use for pagination. If set to `None`, clients may not override the default page size. + +For example, given the following settings: + + REST_FRAMEWORK = { + 'PAGINATE_BY': 10, + 'PAGINATE_BY_PARAM': 'page_size', + } + +A client would be able to modify the pagination size by using the `page_size` query parameter. For example: + + GET http://example.com/api/accounts?page_size=25 + +Default: `None` + +#### MAX_PAGINATE_BY + +The maximum page size to allow when the page size is specified by the client. If set to `None`, then no maximum limit is applied. -The name of a query parameter, which can be used by the client to overide the default page size to use for pagination. If set to `None`, clients may not override the default page size. +For example, given the following settings: + + REST_FRAMEWORK = { + 'PAGINATE_BY': 10, + 'PAGINATE_BY_PARAM': 'page_size', + 'MAX_PAGINATE_BY': 100 + } + +A client request like the following would return a paginated list of up to 100 items. + + GET http://example.com/api/accounts?page_size=999 Default: `None` -## UNAUTHENTICATED_USER +--- + +## Authentication settings + +*The following settings control the behavior of unauthenticated requests.* + +#### UNAUTHENTICATED_USER The class that should be used to initialize `request.user` for unauthenticated requests. Default: `django.contrib.auth.models.AnonymousUser` -## UNAUTHENTICATED_TOKEN +#### UNAUTHENTICATED_TOKEN The class that should be used to initialize `request.auth` for unauthenticated requests. Default: `None` -## FORM_METHOD_OVERRIDE +--- + +## Test settings + +*The following settings control the behavior of APIRequestFactory and APIClient* + +#### TEST_REQUEST_DEFAULT_FORMAT + +The default format that should be used when making test requests. + +This should match up with the format of one of the renderer classes in the `TEST_REQUEST_RENDERER_CLASSES` setting. + +Default: `'multipart'` + +#### TEST_REQUEST_RENDERER_CLASSES + +The renderer classes that are supported when building test requests. + +The format of any of these renderer classes may be used when constructing a test request, for example: `client.post('/users', {'username': 'jamie'}, format='json')` + +Default: + + ( + 'rest_framework.renderers.MultiPartRenderer', + 'rest_framework.renderers.JSONRenderer' + ) + +--- + +## Browser overrides + +*The following settings provide URL or form-based overrides of the default browser behavior.* + +#### FORM_METHOD_OVERRIDE The name of a form field that may be used to override the HTTP method of the form. @@ -132,7 +217,7 @@ If the value of this setting is `None` then form method overloading will be disa Default: `'_method'` -## FORM_CONTENT_OVERRIDE +#### FORM_CONTENT_OVERRIDE The name of a form field that may be used to override the content of the form payload. Must be used together with `FORM_CONTENTTYPE_OVERRIDE`. @@ -140,7 +225,7 @@ If either setting is `None` then form content overloading will be disabled. Default: `'_content'` -## FORM_CONTENTTYPE_OVERRIDE +#### FORM_CONTENTTYPE_OVERRIDE The name of a form field that may be used to override the content type of the form payload. Must be used together with `FORM_CONTENT_OVERRIDE`. @@ -148,7 +233,7 @@ If either setting is `None` then form content overloading will be disabled. Default: `'_content_type'` -## URL_ACCEPT_OVERRIDE +#### URL_ACCEPT_OVERRIDE The name of a URL parameter that may be used to override the HTTP `Accept` header. @@ -156,14 +241,123 @@ If the value of this setting is `None` then URL accept overloading will be disab Default: `'accept'` -## URL_FORMAT_OVERRIDE +#### URL_FORMAT_OVERRIDE + +The name of a URL parameter that may be used to override the default `Accept` header based content negotiation. Default: `'format'` -## FORMAT_SUFFIX_KWARG +--- + +## Date and time formatting + +*The following settings are used to control how date and time representations may be parsed and rendered.* + +#### DATETIME_FORMAT + +A format string that should be used by default for rendering the output of `DateTimeField` serializer fields. If `None`, then `DateTimeField` serializer fields will return Python `datetime` objects, and the datetime encoding will be determined by the renderer. + +May be any of `None`, `'iso-8601'` or a Python [strftime format][strftime] string. + +Default: `None` + +#### DATETIME_INPUT_FORMATS + +A list of format strings that should be used by default for parsing inputs to `DateTimeField` serializer fields. + +May be a list including the string `'iso-8601'` or Python [strftime format][strftime] strings. + +Default: `['iso-8601']` + +#### DATE_FORMAT + +A format string that should be used by default for rendering the output of `DateField` serializer fields. If `None`, then `DateField` serializer fields will return Python `date` objects, and the date encoding will be determined by the renderer. + +May be any of `None`, `'iso-8601'` or a Python [strftime format][strftime] string. + +Default: `None` + +#### DATE_INPUT_FORMATS + +A list of format strings that should be used by default for parsing inputs to `DateField` serializer fields. + +May be a list including the string `'iso-8601'` or Python [strftime format][strftime] strings. + +Default: `['iso-8601']` + +#### TIME_FORMAT + +A format string that should be used by default for rendering the output of `TimeField` serializer fields. If `None`, then `TimeField` serializer fields will return Python `time` objects, and the time encoding will be determined by the renderer. + +May be any of `None`, `'iso-8601'` or a Python [strftime format][strftime] string. + +Default: `None` + +#### TIME_INPUT_FORMATS + +A list of format strings that should be used by default for parsing inputs to `TimeField` serializer fields. + +May be a list including the string `'iso-8601'` or Python [strftime format][strftime] strings. + +Default: `['iso-8601']` + +--- + +## View names and descriptions + +**The following settings are used to generate the view names and descriptions, as used in responses to `OPTIONS` requests, and as used in the browsable API.** + +#### VIEW_NAME_FUNCTION + +A string representing the function that should be used when generating view names. + +This should be a function with the following signature: + + view_name(cls, suffix=None) + +* `cls`: The view class. Typically the name function would inspect the name of the class when generating a descriptive name, by accessing `cls.__name__`. +* `suffix`: The optional suffix used when differentiating individual views in a viewset. + +Default: `'rest_framework.views.get_view_name'` + +#### VIEW_DESCRIPTION_FUNCTION + +A string representing the function that should be used when generating view descriptions. + +This setting can be changed to support markup styles other than the default markdown. For example, you can use it to support `rst` markup in your view docstrings being output in the browsable API. + +This should be a function with the following signature: + + view_description(cls, html=False) + +* `cls`: The view class. Typically the description function would inspect the docstring of the class when generating a description, by accessing `cls.__doc__` +* `html`: A boolean indicating if HTML output is required. `True` when used in the browsable API, and `False` when used in generating `OPTIONS` responses. + +Default: `'rest_framework.views.get_view_description'` + +--- + +## Miscellaneous settings + +#### EXCEPTION_HANDLER + +A string representing the function that should be used when returning a response for any given exception. If the function returns `None`, a 500 error will be raised. + +This setting can be changed to support error responses other than the default `{"detail": "Failure..."}` responses. For example, you can use it to provide API responses like `{"errors": [{"message": "Failure...", "code": ""} ...]}`. + +This should be a function with the following signature: + + exception_handler(exc) + +* `exc`: The exception. + +Default: `'rest_framework.views.exception_handler'` + +#### FORMAT_SUFFIX_KWARG -**TODO** +The name of a parameter in the URL conf that may be used to provide a format suffix. Default: `'format'` [cite]: http://www.python.org/dev/peps/pep-0020/ +[strftime]: http://docs.python.org/2/library/time.html#time.strftime diff --git a/docs/api-guide/status-codes.md b/docs/api-guide/status-codes.md index b50c96ae..409f659b 100644 --- a/docs/api-guide/status-codes.md +++ b/docs/api-guide/status-codes.md @@ -2,13 +2,14 @@ # Status Codes -> 418 I'm a teapot - Any attempt to brew coffee with a teapot should result in the error code "418 I'm a teapot". The resulting entity body MAY be short and stout. +> 418 I'm a teapot - Any attempt to brew coffee with a teapot should result in the error code "418 I'm a teapot". The resulting entity body MAY be short and stout. > > — [RFC 2324][rfc2324], Hyper Text Coffee Pot Control Protocol Using bare status codes in your responses isn't recommended. REST framework includes a set of named constants that you can use to make more code more obvious and readable. from rest_framework import status + from rest_framework.response import Response def empty_view(self): content = {'please move along': 'nothing to see here'} @@ -53,7 +54,7 @@ This class of status code indicates that further action needs to be taken by the ## Client Error - 4xx -The 4xx class of status code is intended for cases in which the client seems to have erred. Except when responding to a HEAD request, the server SHOULD include an entity containing an explanation of the error situation, and whether it is a temporary or permanent condition. +The 4xx class of status code is intended for cases in which the client seems to have erred. Except when responding to a HEAD request, the server SHOULD include an entity containing an explanation of the error situation, and whether it is a temporary or permanent condition. HTTP_400_BAD_REQUEST HTTP_401_UNAUTHORIZED @@ -79,7 +80,7 @@ The 4xx class of status code is intended for cases in which the client seems to ## Server Error - 5xx -Response status codes beginning with the digit "5" indicate cases in which the server is aware that it has erred or is incapable of performing the request. Except when responding to a HEAD request, the server SHOULD include an entity containing an explanation of the error situation, and whether it is a temporary or permanent condition. +Response status codes beginning with the digit "5" indicate cases in which the server is aware that it has erred or is incapable of performing the request. Except when responding to a HEAD request, the server SHOULD include an entity containing an explanation of the error situation, and whether it is a temporary or permanent condition. HTTP_500_INTERNAL_SERVER_ERROR HTTP_501_NOT_IMPLEMENTED diff --git a/docs/api-guide/testing.md b/docs/api-guide/testing.md new file mode 100644 index 00000000..4a8a9168 --- /dev/null +++ b/docs/api-guide/testing.md @@ -0,0 +1,272 @@ +<a class="github" href="test.py"></a> + +# Testing + +> Code without tests is broken as designed. +> +> — [Jacob Kaplan-Moss][cite] + +REST framework includes a few helper classes that extend Django's existing test framework, and improve support for making API requests. + +# APIRequestFactory + +Extends [Django's existing `RequestFactory` class][requestfactory]. + +## Creating test requests + +The `APIRequestFactory` class supports an almost identical API to Django's standard `RequestFactory` class. This means the that standard `.get()`, `.post()`, `.put()`, `.patch()`, `.delete()`, `.head()` and `.options()` methods are all available. + + from rest_framework.test import APIRequestFactory + + # Using the standard RequestFactory API to create a form POST request + factory = APIRequestFactory() + request = factory.post('/notes/', {'title': 'new idea'}) + +#### Using the `format` argument + +Methods which create a request body, such as `post`, `put` and `patch`, include a `format` argument, which make it easy to generate requests using a content type other than multipart form data. For example: + + # Create a JSON POST request + factory = APIRequestFactory() + request = factory.post('/notes/', {'title': 'new idea'}, format='json') + +By default the available formats are `'multipart'` and `'json'`. For compatibility with Django's existing `RequestFactory` the default format is `'multipart'`. + +To support a wider set of request formats, or change the default format, [see the configuration section][configuration]. + +#### Explicitly encoding the request body + +If you need to explicitly encode the request body, you can do so by setting the `content_type` flag. For example: + + request = factory.post('/notes/', json.dumps({'title': 'new idea'}), content_type='application/json') + +#### PUT and PATCH with form data + +One difference worth noting between Django's `RequestFactory` and REST framework's `APIRequestFactory` is that multipart form data will be encoded for methods other than just `.post()`. + +For example, using `APIRequestFactory`, you can make a form PUT request like so: + + factory = APIRequestFactory() + request = factory.put('/notes/547/', {'title': 'remember to email dave'}) + +Using Django's `RequestFactory`, you'd need to explicitly encode the data yourself: + + from django.test.client import encode_multipart, RequestFactory + + factory = RequestFactory() + data = {'title': 'remember to email dave'} + content = encode_multipart('BoUnDaRyStRiNg', data) + content_type = 'multipart/form-data; boundary=BoUnDaRyStRiNg' + request = factory.put('/notes/547/', content, content_type=content_type) + +## Forcing authentication + +When testing views directly using a request factory, it's often convenient to be able to directly authenticate the request, rather than having to construct the correct authentication credentials. + +To forcibly authenticate a request, use the `force_authenticate()` method. + + factory = APIRequestFactory() + user = User.objects.get(username='olivia') + view = AccountDetail.as_view() + + # Make an authenticated request to the view... + request = factory.get('/accounts/django-superstars/') + force_authenticate(request, user=user) + response = view(request) + +The signature for the method is `force_authenticate(request, user=None, token=None)`. When making the call, either or both of the user and token may be set. + +For example, when forcibly authenticating using a token, you might do something like the following: + + user = User.objects.get(username='olivia') + request = factory.get('/accounts/django-superstars/') + force_authenticate(request, user=user, token=user.token) + +--- + +**Note**: When using `APIRequestFactory`, the object that is returned is Django's standard `HttpRequest`, and not REST framework's `Request` object, which is only generated once the view is called. + +This means that setting attributes directly on the request object may not always have the effect you expect. For example, setting `.token` directly will have no effect, and setting `.user` directly will only work if session authentication is being used. + + # Request will only authenticate if `SessionAuthentication` is in use. + request = factory.get('/accounts/django-superstars/') + request.user = user + response = view(request) + +--- + +## Forcing CSRF validation + +By default, requests created with `APIRequestFactory` will not have CSRF validation applied when passed to a REST framework view. If you need to explicitly turn CSRF validation on, you can do so by setting the `enforce_csrf_checks` flag when instantiating the factory. + + factory = APIRequestFactory(enforce_csrf_checks=True) + +--- + +**Note**: It's worth noting that Django's standard `RequestFactory` doesn't need to include this option, because when using regular Django the CSRF validation takes place in middleware, which is not run when testing views directly. When using REST framework, CSRF validation takes place inside the view, so the request factory needs to disable view-level CSRF checks. + +--- + +# APIClient + +Extends [Django's existing `Client` class][client]. + +## Making requests + +The `APIClient` class supports the same request interface as `APIRequestFactory`. This means the that standard `.get()`, `.post()`, `.put()`, `.patch()`, `.delete()`, `.head()` and `.options()` methods are all available. For example: + + from rest_framework.test import APIClient + + client = APIClient() + client.post('/notes/', {'title': 'new idea'}, format='json') + +To support a wider set of request formats, or change the default format, [see the configuration section][configuration]. + +## Authenticating + +#### .login(**kwargs) + +The `login` method functions exactly as it does with Django's regular `Client` class. This allows you to authenticate requests against any views which include `SessionAuthentication`. + + # Make all requests in the context of a logged in session. + client = APIClient() + client.login(username='lauren', password='secret') + +To logout, call the `logout` method as usual. + + # Log out + client.logout() + +The `login` method is appropriate for testing APIs that use session authentication, for example web sites which include AJAX interaction with the API. + +#### .credentials(**kwargs) + +The `credentials` method can be used to set headers that will then be included on all subsequent requests by the test client. + + from rest_framework.authtoken.models import Token + from rest_framework.test import APIClient + + # Include an appropriate `Authorization:` header on all requests. + token = Token.objects.get(user__username='lauren') + client = APIClient() + client.credentials(HTTP_AUTHORIZATION='Token ' + token.key) + +Note that calling `credentials` a second time overwrites any existing credentials. You can unset any existing credentials by calling the method with no arguments. + + # Stop including any credentials + client.credentials() + +The `credentials` method is appropriate for testing APIs that require authentication headers, such as basic authentication, OAuth1a and OAuth2 authentication, and simple token authentication schemes. + +#### .force_authenticate(user=None, token=None) + +Sometimes you may want to bypass authentication, and simple force all requests by the test client to be automatically treated as authenticated. + +This can be a useful shortcut if you're testing the API but don't want to have to construct valid authentication credentials in order to make test requests. + + user = User.objects.get(username='lauren') + client = APIClient() + client.force_authenticate(user=user) + +To unauthenticate subsequent requests, call `force_authenticate` setting the user and/or token to `None`. + + client.force_authenticate(user=None) + +## CSRF validation + +By default CSRF validation is not applied when using `APIClient`. If you need to explicitly enable CSRF validation, you can do so by setting the `enforce_csrf_checks` flag when instantiating the client. + + client = APIClient(enforce_csrf_checks=True) + +As usual CSRF validation will only apply to any session authenticated views. This means CSRF validation will only occur if the client has been logged in by calling `login()`. + +--- + +# Test cases + +REST framework includes the following test case classes, that mirror the existing Django test case classes, but use `APIClient` instead of Django's default `Client`. + +* `APISimpleTestCase` +* `APITransactionTestCase` +* `APITestCase` +* `APILiveServerTestCase` + +## Example + +You can use any of REST framework's test case classes as you would for the regular Django test case classes. The `self.client` attribute will be an `APIClient` instance. + + from django.core.urlresolvers import reverse + from rest_framework import status + from rest_framework.test import APITestCase + + class AccountTests(APITestCase): + def test_create_account(self): + """ + Ensure we can create a new account object. + """ + url = reverse('account-list') + data = {'name': 'DabApps'} + response = self.client.post(url, data, format='json') + self.assertEqual(response.status_code, status.HTTP_201_CREATED) + self.assertEqual(response.data, data) + +--- + +# Testing responses + +## Checking the response data + +When checking the validity of test responses it's often more convenient to inspect the data that the response was created with, rather than inspecting the fully rendered response. + +For example, it's easier to inspect `request.data`: + + response = self.client.get('/users/4/') + self.assertEqual(response.data, {'id': 4, 'username': 'lauren'}) + +Instead of inspecting the result of parsing `request.content`: + + response = self.client.get('/users/4/') + self.assertEqual(json.loads(response.content), {'id': 4, 'username': 'lauren'}) + +## Rendering responses + +If you're testing views directly using `APIRequestFactory`, the responses that are returned will not yet be rendered, as rendering of template responses is performed by Django's internal request-response cycle. In order to access `response.content`, you'll first need to render the response. + + view = UserDetail.as_view() + request = factory.get('/users/4') + response = view(request, pk='4') + response.render() # Cannot access `response.content` without this. + self.assertEqual(response.content, '{"username": "lauren", "id": 4}') + +--- + +# Configuration + +## Setting the default format + +The default format used to make test requests may be set using the `TEST_REQUEST_DEFAULT_FORMAT` setting key. For example, to always use JSON for test requests by default instead of standard multipart form requests, set the following in your `settings.py` file: + + REST_FRAMEWORK = { + ... + 'TEST_REQUEST_DEFAULT_FORMAT': 'json' + } + +## Setting the available formats + +If you need to test requests using something other than multipart or json requests, you can do so by setting the `TEST_REQUEST_RENDERER_CLASSES` setting. + +For example, to add support for using `format='yaml'` in test requests, you might have something like this in your `settings.py` file. + + REST_FRAMEWORK = { + ... + 'TEST_REQUEST_RENDERER_CLASSES': ( + 'rest_framework.renderers.MultiPartRenderer', + 'rest_framework.renderers.JSONRenderer', + 'rest_framework.renderers.YAMLRenderer' + ) + } + +[cite]: http://jacobian.org/writing/django-apps-with-buildout/#s-create-a-test-wrapper +[client]: https://docs.djangoproject.com/en/dev/topics/testing/overview/#module-django.test.client +[requestfactory]: https://docs.djangoproject.com/en/dev/topics/testing/advanced/#django.test.client.RequestFactory +[configuration]: #configuration diff --git a/docs/api-guide/throttling.md b/docs/api-guide/throttling.md index b03bc9e0..fc1525df 100644 --- a/docs/api-guide/throttling.md +++ b/docs/api-guide/throttling.md @@ -6,15 +6,13 @@ > > [Twitter API rate limiting response][cite] -[cite]: https://dev.twitter.com/docs/error-codes-responses - Throttling is similar to [permissions], in that it determines if a request should be authorized. Throttles indicate a temporary state, and are used to control the rate of requests that clients can make to an API. As with permissions, multiple throttles may be used. Your API might have a restrictive throttle for unauthenticated requests, and a less restrictive throttle for authenticated requests. Another scenario where you might want to use multiple throttles would be if you need to impose different constraints on different parts of the API, due to some services being particularly resource-intensive. -Multiple throttles can also be used if you want to impose both burst throttling rates, and sustained throttling rates. For example, you might want to limit a user to a maximum of 60 requests per minute, and 1000 requests per day. +Multiple throttles can also be used if you want to impose both burst throttling rates, and sustained throttling rates. For example, you might want to limit a user to a maximum of 60 requests per minute, and 1000 requests per day. Throttles do not necessarily only refer to rate-limiting requests. For example a storage service might also need to throttle against bandwidth, and a paid data service might want to throttle against a certain number of a records being accessed. @@ -42,10 +40,15 @@ The default throttling policy may be set globally, using the `DEFAULT_THROTTLE_C The rate descriptions used in `DEFAULT_THROTTLE_RATES` may include `second`, `minute`, `hour` or `day` as the throttle period. -You can also set the throttling policy on a per-view basis, using the `APIView` class based views. +You can also set the throttling policy on a per-view or per-viewset basis, +using the `APIView` class based views. + + from rest_framework.response import Response + from rest_framework.throttling import UserRateThrottle + from rest_framework.views import APIView class ExampleView(APIView): - throttle_classes = (UserThrottle,) + throttle_classes = (UserRateThrottle,) def get(self, request, format=None): content = { @@ -56,35 +59,46 @@ You can also set the throttling policy on a per-view basis, using the `APIView` Or, if you're using the `@api_view` decorator with function based views. @api_view('GET') - @throttle_classes(UserThrottle) + @throttle_classes([UserRateThrottle]) def example_view(request, format=None): content = { 'status': 'request was permitted' } return Response(content) +## Setting up the cache + +The throttle classes provided by REST framework use Django's cache backend. You should make sure that you've set appropriate [cache settings][cache-setting]. The default value of `LocMemCache` backend should be okay for simple setups. See Django's [cache documentation][cache-docs] for more details. + +If you need to use a cache other than `'default'`, you can do so by creating a custom throttle class and setting the `cache` attribute. For example: + + class CustomAnonRateThrottle(AnonRateThrottle): + cache = get_cache('alternate') + +You'll need to rememeber to also set your custom throttle class in the `'DEFAULT_THROTTLE_CLASSES'` settings key, or using the `throttle_classes` view attribute. + --- # API Reference ## AnonRateThrottle -The `AnonThrottle` will only ever throttle unauthenticated users. The IP address of the incoming request is used to generate a unique key to throttle against. +The `AnonRateThrottle` will only ever throttle unauthenticated users. The IP address of the incoming request is used to generate a unique key to throttle against. The allowed request rate is determined from one of the following (in order of preference). -* The `rate` property on the class, which may be provided by overriding `AnonThrottle` and setting the property. +* The `rate` property on the class, which may be provided by overriding `AnonRateThrottle` and setting the property. * The `DEFAULT_THROTTLE_RATES['anon']` setting. -`AnonThrottle` is suitable if you want to restrict the rate of requests from unknown sources. +`AnonRateThrottle` is suitable if you want to restrict the rate of requests from unknown sources. ## UserRateThrottle -The `UserThrottle` will throttle users to a given rate of requests across the API. The user id is used to generate a unique key to throttle against. Unauthenticated requests will fall back to using the IP address of the incoming request to generate a unique key to throttle against. +The `UserRateThrottle` will throttle users to a given rate of requests across the API. The user id is used to generate a unique key to throttle against. Unauthenticated requests will fall back to using the IP address of the incoming request to generate a unique key to throttle against. The allowed request rate is determined from one of the following (in order of preference). -* The `rate` property on the class, which may be provided by overriding `UserThrottle` and setting the property. +* The `rate` property on the class, which may be provided by overriding `UserRateThrottle` and setting the property. * The `DEFAULT_THROTTLE_RATES['user']` setting. An API may have multiple `UserRateThrottles` in place at the same time. To do so, override `UserRateThrottle` and set a unique "scope" for each class. @@ -110,11 +124,11 @@ For example, multiple user throttle rates could be implemented by using the foll } } -`UserThrottle` is suitable if you want simple global rate restrictions per-user. +`UserRateThrottle` is suitable if you want simple global rate restrictions per-user. ## ScopedRateThrottle -The `ScopedThrottle` class can be used to restrict access to specific parts of the API. This throttle will only be applied if the view that is being accessed includes a `.throttle_scope` property. The unique throttle key will then be formed by concatenating the "scope" of the request with the unique user id or IP address. +The `ScopedRateThrottle` class can be used to restrict access to specific parts of the API. This throttle will only be applied if the view that is being accessed includes a `.throttle_scope` property. The unique throttle key will then be formed by concatenating the "scope" of the request with the unique user id or IP address. The allowed request rate is determined by the `DEFAULT_THROTTLE_RATES` setting using a key from the request "scope". @@ -150,8 +164,19 @@ User requests to either `ContactListView` or `ContactDetailView` would be restri # Custom throttles -To create a custom throttle, override `BaseThrottle` and implement `.allow_request(request, view)`. The method should return `True` if the request should be allowed, and `False` otherwise. +To create a custom throttle, override `BaseThrottle` and implement `.allow_request(self, request, view)`. The method should return `True` if the request should be allowed, and `False` otherwise. Optionally you may also override the `.wait()` method. If implemented, `.wait()` should return a recommended number of seconds to wait before attempting the next request, or `None`. The `.wait()` method will only be called if `.allow_request()` has previously returned `False`. +## Example + +The following is an example of a rate throttle, that will randomly throttle 1 in every 10 requests. + + class RandomRateThrottle(throttles.BaseThrottle): + def allow_request(self, request, view): + return random.randint(1, 10) == 1 + +[cite]: https://dev.twitter.com/docs/error-codes-responses [permissions]: permissions.md +[cache-setting]: https://docs.djangoproject.com/en/dev/ref/settings/#caches +[cache-docs]: https://docs.djangoproject.com/en/dev/topics/cache/#setting-up-the-cache diff --git a/docs/api-guide/views.md b/docs/api-guide/views.md index 5b072827..194a7a6b 100644 --- a/docs/api-guide/views.md +++ b/docs/api-guide/views.md @@ -19,6 +19,10 @@ Using the `APIView` class is pretty much the same as using a regular `View` clas For example: + from rest_framework.views import APIView + from rest_framework.response import Response + from rest_framework import authentication, permissions + class ListUsers(APIView): """ View to list all users in the system. @@ -72,16 +76,16 @@ The following methods are used by REST framework to instantiate the various plug The following methods are called before dispatching to the handler method. -### .check_permissions(...) +### .check_permissions(self, request) -### .check_throttles(...) +### .check_throttles(self, request) -### .perform_content_negotiation(...) +### .perform_content_negotiation(self, request, force=False) ## Dispatch methods The following methods are called directly by the view's `.dispatch()` method. -These perform any actions that need to occur before or after calling the handler methods such as `.get()`, `.post()`, `put()` and `.delete()`. +These perform any actions that need to occur before or after calling the handler methods such as `.get()`, `.post()`, `put()`, `patch()` and `.delete()`. ### .initial(self, request, \*args, **kwargs) @@ -106,7 +110,7 @@ You won't typically need to override this method. ### .finalize_response(self, request, response, \*args, **kwargs) -Ensures that any `Response` object returned from the handler method will be rendered into the correct content type, as determined by the content negotation. +Ensures that any `Response` object returned from the handler method will be rendered into the correct content type, as determined by the content negotiation. You won't typically need to override this method. @@ -118,13 +122,13 @@ You won't typically need to override this method. > > — [Nick Coghlan][cite2] -REST framework also allows you to work with regular function based views. It provides a set of simple decorators that wrap your function based views to ensure they receive an instance of `Request` (rather than the usual Django `HttpRequest`) and allows them to return a `Response` (instead of a Django `HttpResponse`), and allow you to configure how the request is processed. +REST framework also allows you to work with regular function based views. It provides a set of simple decorators that wrap your function based views to ensure they receive an instance of `Request` (rather than the usual Django `HttpRequest`) and allows them to return a `Response` (instead of a Django `HttpResponse`), and allow you to configure how the request is processed. ## @api_view() **Signature:** `@api_view(http_method_names)` -The core of this functionality is the `api_view` decorator, which takes a list of HTTP methods that your view should respond to. For example, this is how you would write a very simple view that just manually returns some data: +The core of this functionality is the `api_view` decorator, which takes a list of HTTP methods that your view should respond to. For example, this is how you would write a very simple view that just manually returns some data: from rest_framework.decorators import api_view @@ -133,11 +137,11 @@ The core of this functionality is the `api_view` decorator, which takes a list o return Response({"message": "Hello, world!"}) -This view will use the default renderers, parsers, authentication classes etc specified in the [settings](settings). +This view will use the default renderers, parsers, authentication classes etc specified in the [settings]. ## API policy decorators -To override the default settings, REST framework provides a set of additional decorators which can be added to your views. These must come *after* (below) the `@api_view` decorator. For example, to create a view that uses a [throttle](throttling) to ensure it can only be called once per day by a particular user, use the `@throttle_classes` decorator, passing a list of throttle classes: +To override the default settings, REST framework provides a set of additional decorators which can be added to your views. These must come *after* (below) the `@api_view` decorator. For example, to create a view that uses a [throttle][throttling] to ensure it can only be called once per day by a particular user, use the `@throttle_classes` decorator, passing a list of throttle classes: from rest_framework.decorators import api_view, throttle_classes from rest_framework.throttling import UserRateThrottle @@ -164,5 +168,5 @@ Each of these decorators takes a single argument which must be a list or tuple o [cite]: http://reinout.vanrees.org/weblog/2011/08/24/class-based-views-usage.html [cite2]: http://www.boredomandlaziness.org/2012/05/djangos-cbvs-are-not-mistake-but.html -[settings]: api-guide/settings.md -[throttling]: api-guide/throttling.md +[settings]: settings.md +[throttling]: throttling.md diff --git a/docs/api-guide/viewsets.md b/docs/api-guide/viewsets.md new file mode 100644 index 00000000..4fdd9364 --- /dev/null +++ b/docs/api-guide/viewsets.md @@ -0,0 +1,237 @@ +<a class="github" href="viewsets.py"></a> + +# ViewSets + +> After routing has determined which controller to use for a request, your controller is responsible for making sense of the request and producing the appropriate output. +> +> — [Ruby on Rails Documentation][cite] + + +Django REST framework allows you to combine the logic for a set of related views in a single class, called a `ViewSet`. In other frameworks you may also find conceptually similar implementations named something like 'Resources' or 'Controllers'. + +A `ViewSet` class is simply **a type of class-based View, that does not provide any method handlers** such as `.get()` or `.post()`, and instead provides actions such as `.list()` and `.create()`. + +The method handlers for a `ViewSet` are only bound to the corresponding actions at the point of finalizing the view, using the `.as_view()` method. + +Typically, rather than explicitly registering the views in a viewset in the urlconf, you'll register the viewset with a router class, that automatically determines the urlconf for you. + +## Example + +Let's define a simple viewset that can be used to list or retrieve all the users in the system. + + from django.contrib.auth.models import User + from django.shortcuts import get_object_or_404 + from myapps.serializers import UserSerializer + from rest_framework import viewsets + from rest_framework.response import Response + + class UserViewSet(viewsets.ViewSet): + """ + A simple ViewSet that for listing or retrieving users. + """ + def list(self, request): + queryset = User.objects.all() + serializer = UserSerializer(queryset, many=True) + return Response(serializer.data) + + def retrieve(self, request, pk=None): + queryset = User.objects.all() + user = get_object_or_404(queryset, pk=pk) + serializer = UserSerializer(user) + return Response(serializer.data) + +If we need to, we can bind this viewset into two separate views, like so: + + user_list = UserViewSet.as_view({'get': 'list'}) + user_detail = UserViewSet.as_view({'get': 'retrieve'}) + +Typically we wouldn't do this, but would instead register the viewset with a router, and allow the urlconf to be automatically generated. + + from myapp.views import UserViewSet + from rest_framework.routers import DefaultRouter + + router = DefaultRouter() + router.register(r'users', UserViewSet) + urlpatterns = router.urls + +Rather than writing your own viewsets, you'll often want to use the existing base classes that provide a default set of behavior. For example: + + class UserViewSet(viewsets.ModelViewSet): + """ + A viewset for viewing and editing user instances. + """ + serializer_class = UserSerializer + queryset = User.objects.all() + +There are two main advantages of using a `ViewSet` class over using a `View` class. + +* Repeated logic can be combined into a single class. In the above example, we only need to specify the `queryset` once, and it'll be used across multiple views. +* By using routers, we no longer need to deal with wiring up the URL conf ourselves. + +Both of these come with a trade-off. Using regular views and URL confs is more explicit and gives you more control. ViewSets are helpful if you want to get up and running quickly, or when you have a large API and you want to enforce a consistent URL configuration throughout. + +## Marking extra methods for routing + +The default routers included with REST framework will provide routes for a standard set of create/retrieve/update/destroy style operations, as shown below: + + class UserViewSet(viewsets.ViewSet): + """ + Example empty viewset demonstrating the standard + actions that will be handled by a router class. + + If you're using format suffixes, make sure to also include + the `format=None` keyword argument for each action. + """ + + def list(self, request): + pass + + def create(self, request): + pass + + def retrieve(self, request, pk=None): + pass + + def update(self, request, pk=None): + pass + + def partial_update(self, request, pk=None): + pass + + def destroy(self, request, pk=None): + pass + +If you have ad-hoc methods that you need to be routed to, you can mark them as requiring routing using the `@link` or `@action` decorators. The `@link` decorator will route `GET` requests, and the `@action` decorator will route `POST` requests. + +For example: + + from django.contrib.auth.models import User + from rest_framework import viewsets + from rest_framework import status + from rest_framework.decorators import action + from rest_framework.response import Response + from myapp.serializers import UserSerializer, PasswordSerializer + + class UserViewSet(viewsets.ModelViewSet): + """ + A viewset that provides the standard actions + """ + queryset = User.objects.all() + serializer_class = UserSerializer + + @action() + def set_password(self, request, pk=None): + user = self.get_object() + serializer = PasswordSerializer(data=request.DATA) + if serializer.is_valid(): + user.set_password(serializer.data['password']) + user.save() + return Response({'status': 'password set'}) + else: + return Response(serializer.errors, + status=status.HTTP_400_BAD_REQUEST) + +The `@action` and `@link` decorators can additionally take extra arguments that will be set for the routed view only. For example... + + @action(permission_classes=[IsAdminOrIsSelf]) + def set_password(self, request, pk=None): + ... + +The `@action` decorator will route `POST` requests by default, but may also accept other HTTP methods, by using the `method` argument. For example: + + @action(methods=['POST', 'DELETE']) + def unset_password(self, request, pk=None): + ... + +The two new actions will then be available at the urls `^users/{pk}/set_password/$` and `^users/{pk}/unset_password/$` + + +--- + +# API Reference + +## ViewSet + +The `ViewSet` class inherits from `APIView`. You can use any of the standard attributes such as `permission_classes`, `authentication_classes` in order to control the API policy on the viewset. + +The `ViewSet` class does not provide any implementations of actions. In order to use a `ViewSet` class you'll override the class and define the action implementations explicitly. + +## GenericViewSet + +The `GenericViewSet` class inherits from `GenericAPIView`, and provides the default set of `get_object`, `get_queryset` methods and other generic view base behavior, but does not include any actions by default. + +In order to use a `GenericViewSet` class you'll override the class and either mixin the required mixin classes, or define the action implementations explicitly. + +## ModelViewSet + +The `ModelViewSet` class inherits from `GenericAPIView` and includes implementations for various actions, by mixing in the behavior of the various mixin classes. + +The actions provided by the `ModelViewSet` class are `.list()`, `.retrieve()`, `.create()`, `.update()`, and `.destroy()`. + +#### Example + +Because `ModelViewSet` extends `GenericAPIView`, you'll normally need to provide at least the `queryset` and `serializer_class` attributes, or the `model` attribute shortcut. For example: + + class AccountViewSet(viewsets.ModelViewSet): + """ + A simple ViewSet for viewing and editing accounts. + """ + queryset = Account.objects.all() + serializer_class = AccountSerializer + permission_classes = [IsAccountAdminOrReadOnly] + +Note that you can use any of the standard attributes or method overrides provided by `GenericAPIView`. For example, to use a `ViewSet` that dynamically determines the queryset it should operate on, you might do something like this: + + class AccountViewSet(viewsets.ModelViewSet): + """ + A simple ViewSet for viewing and editing the accounts + associated with the user. + """ + serializer_class = AccountSerializer + permission_classes = [IsAccountAdminOrReadOnly] + + def get_queryset(self): + return self.request.user.accounts.all() + +Also note that although this class provides the complete set of create/list/retrieve/update/destroy actions by default, you can restrict the available operations by using the standard permission classes. + +## ReadOnlyModelViewSet + +The `ReadOnlyModelViewSet` class also inherits from `GenericAPIView`. As with `ModelViewSet` it also includes implementations for various actions, but unlike `ModelViewSet` only provides the 'read-only' actions, `.list()` and `.retrieve()`. + +#### Example + +As with `ModelViewSet`, you'll normally need to provide at least the `queryset` and `serializer_class` attributes. For example: + + class AccountViewSet(viewsets.ReadOnlyModelViewSet): + """ + A simple ViewSet for viewing accounts. + """ + queryset = Account.objects.all() + serializer_class = AccountSerializer + +Again, as with `ModelViewSet`, you can use any of the standard attributes and method overrides available to `GenericAPIView`. + +# Custom ViewSet base classes + +You may need to provide custom `ViewSet` classes that do not have the full set of `ModelViewSet` actions, or that customize the behavior in some other way. + +## Example + +To create a base viewset class that provides `create`, `list` and `retrieve` operations, inherit from `GenericViewSet`, and mixin the required actions: + + class CreateListRetrieveViewSet(mixins.CreateModelMixin, + mixins.ListModelMixin, + mixins.RetrieveModelMixin, + viewsets.GenericViewSet): + """ + A viewset that provides `retrieve`, `update`, and `list` actions. + + To use it, override the class and set the `.queryset` and + `.serializer_class` attributes. + """ + pass + +By creating your own base `ViewSet` classes, you can provide common behavior that can be reused in multiple viewsets across your API. + +[cite]: http://guides.rubyonrails.org/routing.html |