From 51fae73f3d565e2702c72ff9841cc072d6490804 Mon Sep 17 00:00:00 2001 From: Jamie Matthews Date: Wed, 24 Oct 2012 09:28:10 +0100 Subject: Implement per-field validation on Serializers --- docs/api-guide/serializers.md | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) (limited to 'docs/api-guide') diff --git a/docs/api-guide/serializers.md b/docs/api-guide/serializers.md index c10a3f44..e1e12e74 100644 --- a/docs/api-guide/serializers.md +++ b/docs/api-guide/serializers.md @@ -78,6 +78,23 @@ When deserializing data, you always need to call `is_valid()` before attempting **TODO: Describe validation in more depth** +## Custom field validation + +Like Django forms, you can specify custom field-level validation by adding `clean_()` methods to your `Serializer` subclass. This method takes a dictionary of deserialized data as a first argument, and the field name in that data as a second argument (which will be either the name of the field or the value of the `source` argument, if one was provided.) It should either return the data dictionary or raise a `ValidationError`. For example: + + class BlogPostSerializer(Serializer): + title = serializers.CharField(max_length=100) + content = serializers.CharField() + + def clean_title(self, data, source): + """ + Check that the blog post is about Django + """ + value = data[source] + if "Django" not in value: + raise ValidationError("Blog post is not about Django") + return data + ## 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, -- cgit v1.2.3 From 388a807f64f60d84556288e2ade4f0fe57a8e66b Mon Sep 17 00:00:00 2001 From: Jamie Matthews Date: Wed, 24 Oct 2012 11:27:01 +0100 Subject: Switch from clean_ to validate_, clarify documentation --- docs/api-guide/serializers.md | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) (limited to 'docs/api-guide') diff --git a/docs/api-guide/serializers.md b/docs/api-guide/serializers.md index e1e12e74..9011d31f 100644 --- a/docs/api-guide/serializers.md +++ b/docs/api-guide/serializers.md @@ -80,19 +80,21 @@ When deserializing data, you always need to call `is_valid()` before attempting ## Custom field validation -Like Django forms, you can specify custom field-level validation by adding `clean_()` methods to your `Serializer` subclass. This method takes a dictionary of deserialized data as a first argument, and the field name in that data as a second argument (which will be either the name of the field or the value of the `source` argument, if one was provided.) It should either return the data dictionary or raise a `ValidationError`. For example: +You can specify custom field-level validation by adding `validate_()` methods to your `Serializer` subclass. These are analagous to `clean_` methods on Django forms, but accept slightly different arguments. They take a dictionary of deserialized data as a first argument, and the field name in that data 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_` methods should either just return the data dictionary or raise a `ValidationError`. For example: - class BlogPostSerializer(Serializer): + from rest_framework import serializers + + class BlogPostSerializer(serializers.Serializer): title = serializers.CharField(max_length=100) content = serializers.CharField() - def clean_title(self, data, source): + def validate_title(self, data, source): """ Check that the blog post is about Django """ value = data[source] if "Django" not in value: - raise ValidationError("Blog post is not about Django") + raise serializers.ValidationError("Blog post is not about Django") return data ## Dealing with nested objects -- cgit v1.2.3 From ac2d39892d6b3fbbe5cd53b9ef83367249ba4880 Mon Sep 17 00:00:00 2001 From: Jamie Matthews Date: Wed, 24 Oct 2012 11:39:17 +0100 Subject: Add cross-field validate method --- docs/api-guide/serializers.md | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) (limited to 'docs/api-guide') diff --git a/docs/api-guide/serializers.md b/docs/api-guide/serializers.md index 9011d31f..40f8a170 100644 --- a/docs/api-guide/serializers.md +++ b/docs/api-guide/serializers.md @@ -76,9 +76,7 @@ Deserialization is similar. First we parse a stream into python native datatype 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. -**TODO: Describe validation in more depth** - -## Custom field validation +### Field-level validation You can specify custom field-level validation by adding `validate_()` methods to your `Serializer` subclass. These are analagous to `clean_` methods on Django forms, but accept slightly different arguments. They take a dictionary of deserialized data as a first argument, and the field name in that data 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_` methods should either just return the data dictionary or raise a `ValidationError`. For example: @@ -97,6 +95,10 @@ You can specify custom field-level validation by adding `validate_()` raise serializers.ValidationError("Blog post is not about Django") return data +### Final cross-field 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`. + ## 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, -- cgit v1.2.3 From d60d598e0255fb3d55a1213d1025447d83523658 Mon Sep 17 00:00:00 2001 From: Jamie Matthews Date: Wed, 24 Oct 2012 11:43:30 +0100 Subject: Clean up internal names and documentation --- docs/api-guide/serializers.md | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'docs/api-guide') diff --git a/docs/api-guide/serializers.md b/docs/api-guide/serializers.md index 40f8a170..50505d30 100644 --- a/docs/api-guide/serializers.md +++ b/docs/api-guide/serializers.md @@ -78,7 +78,7 @@ When deserializing data, you always need to call `is_valid()` before attempting ### Field-level validation -You can specify custom field-level validation by adding `validate_()` methods to your `Serializer` subclass. These are analagous to `clean_` methods on Django forms, but accept slightly different arguments. They take a dictionary of deserialized data as a first argument, and the field name in that data 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_` methods should either just return the data dictionary or raise a `ValidationError`. For example: +You can specify custom field-level validation by adding `validate_()` methods to your `Serializer` subclass. These are analagous to `clean_` 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_` methods should either just return the attrs dictionary or raise a `ValidationError`. For example: from rest_framework import serializers @@ -86,14 +86,14 @@ You can specify custom field-level validation by adding `validate_()` title = serializers.CharField(max_length=100) content = serializers.CharField() - def validate_title(self, data, source): + def validate_title(self, attrs, source): """ Check that the blog post is about Django """ - value = data[source] + value = attrs[source] if "Django" not in value: raise serializers.ValidationError("Blog post is not about Django") - return data + return attrs ### Final cross-field validation -- cgit v1.2.3