More refactoring - move various less core stuff into utils etc

1 files changed, 84 insertions, 0 deletions

diff --git a/djangorestframework/authentication.py b/djangorestframework/authentication.py
new file mode 100644
index 00000000..894b34fc
--- /dev/null
+++ b/djangorestframework/authentication.py
@@ -0,0 +1,84 @@
+"""The :mod:`authentication` modules provides for pluggable authentication behaviour.
+
+Authentication behaviour is provided by adding the mixin class :class:`AuthenticatorMixin` to a :class:`.Resource` or Django :class:`View` class.
+
+The set of authentication which are use is then specified by setting the :attr:`authentication` attribute on the class, and listing a set of authentication classes.
+"""
+from django.contrib.auth import authenticate
+from django.middleware.csrf import CsrfViewMiddleware
+from djangorestframework.utils import as_tuple
+import base64
+
+
+class BaseAuthenticator(object):
+    """All authentication should extend BaseAuthenticator."""
+
+    def __init__(self, view):
+        """Initialise the authentication with the mixin instance as state,
+        in case the authentication needs to access any metadata on the mixin object."""
+        self.view = view
+
+    def authenticate(self, request):
+        """Authenticate the request and return the authentication context or None.
+
+        An authentication context might be something as simple as a User object, or it might
+        be some more complicated token, for example authentication tokens which are signed
+        against a particular set of permissions for a given user, over a given timeframe.
+
+        The default permission checking on Resource will use the allowed_methods attribute
+        for permissions if the authentication context is not None, and use anon_allowed_methods otherwise.
+
+        The authentication context is available to the method calls eg Resource.get(request)
+        by accessing self.auth in order to allow them to apply any more fine grained permission
+        checking at the point the response is being generated.
+        
+        This function must be overridden to be implemented."""
+        return None
+
+
+class BasicAuthenticator(BaseAuthenticator):
+    """Use HTTP Basic authentication"""
+    def authenticate(self, request):
+        from django.utils.encoding import smart_unicode, DjangoUnicodeDecodeError
+        
+        if 'HTTP_AUTHORIZATION' in request.META:
+            auth = request.META['HTTP_AUTHORIZATION'].split()
+            if len(auth) == 2 and auth[0].lower() == "basic":
+                try:
+                    auth_parts = base64.b64decode(auth[1]).partition(':')
+                except TypeError:
+                    return None
+                
+                try:
+                    uname, passwd = smart_unicode(auth_parts[0]), smart_unicode(auth_parts[2])
+                except DjangoUnicodeDecodeError:
+                    return None
+                    
+                user = authenticate(username=uname, password=passwd)
+                if user is not None and user.is_active:
+                    return user
+        return None
+                
+
+class UserLoggedInAuthenticator(BaseAuthenticator):
+    """Use Django's built-in request session for authentication."""
+    def authenticate(self, request):
+        if getattr(request, 'user', None) and request.user.is_active:
+            # If this is a POST request we enforce CSRF validation.
+            if request.method.upper() == 'POST':
+                # Temporarily replace request.POST with .RAW_CONTENT,
+                # so that we use our more generic request parsing
+                request._post = self.view.RAW_CONTENT
+                resp = CsrfViewMiddleware().process_view(request, None, (), {})
+                del(request._post)
+                if resp is not None:  # csrf failed
+                    return None
+            return request.user
+        return None
+
+
+#class DigestAuthentication(BaseAuthentication):
+#    pass
+#
+#class OAuthAuthentication(BaseAuthentication):
+#    pass