Merge branch 'master' into topic/openapi-operation-plural

README.md

@@ -21,14 +21,14 @@ The initial aim is to provide a single full-time position on REST framework.
 
 [![][sentry-img]][sentry-url]
 [![][stream-img]][stream-url]
-[![][rollbar-img]][rollbar-url]
+[![][spacinov-img]][spacinov-url]
-[![][esg-img]][esg-url]
 [![][retool-img]][retool-url]
 [![][bitio-img]][bitio-url]
 [![][posthog-img]][posthog-url]
 [![][cryptapi-img]][cryptapi-url]
+[![][fezto-img]][fezto-url]
 
-Many thanks to all our [wonderful sponsors][sponsors], and in particular to our premium backers, [Sentry][sentry-url], [Stream][stream-url], [Rollbar][rollbar-url], [ESG][esg-url], [Retool][retool-url], [bit.io][bitio-url], [PostHog][posthog-url], and [CryptAPI][cryptapi-url].
+Many thanks to all our [wonderful sponsors][sponsors], and in particular to our premium backers, [Sentry][sentry-url], [Stream][stream-url], [Spacinov][spacinov-url], [Retool][retool-url], [bit.io][bitio-url], [PostHog][posthog-url], [CryptAPI][cryptapi-url], and [FEZTO][fezto-url].
 
 ---
 
@@ -55,7 +55,7 @@ There is a live example API for testing purposes, [available here][sandbox].
 # Requirements
 
 * Python (3.6, 3.7, 3.8, 3.9, 3.10)
-* Django (2.2, 3.0, 3.1, 3.2, 4.0)
+* Django (2.2, 3.0, 3.1, 3.2, 4.0, 4.1)
 
 We **highly recommend** and only officially support the latest patch release of
 each Python and Django series.
@@ -194,21 +194,21 @@ Please see the [security policy][security-policy].
 
 [sentry-img]: https://raw.githubusercontent.com/encode/django-rest-framework/master/docs/img/premium/sentry-readme.png
 [stream-img]: https://raw.githubusercontent.com/encode/django-rest-framework/master/docs/img/premium/stream-readme.png
-[rollbar-img]: https://raw.githubusercontent.com/encode/django-rest-framework/master/docs/img/premium/rollbar-readme.png
+[spacinov-img]: https://raw.githubusercontent.com/encode/django-rest-framework/master/docs/img/premium/spacinov-readme.png
-[esg-img]: https://raw.githubusercontent.com/encode/django-rest-framework/master/docs/img/premium/esg-readme.png
 [retool-img]: https://raw.githubusercontent.com/encode/django-rest-framework/master/docs/img/premium/retool-readme.png
 [bitio-img]: https://raw.githubusercontent.com/encode/django-rest-framework/master/docs/img/premium/bitio-readme.png
 [posthog-img]: https://raw.githubusercontent.com/encode/django-rest-framework/master/docs/img/premium/posthog-readme.png
 [cryptapi-img]: https://raw.githubusercontent.com/encode/django-rest-framework/master/docs/img/premium/cryptapi-readme.png
+[fezto-img]: https://raw.githubusercontent.com/encode/django-rest-framework/master/docs/img/premium/fezto-readme.png
 
 [sentry-url]: https://getsentry.com/welcome/
 [stream-url]: https://getstream.io/?utm_source=DjangoRESTFramework&utm_medium=Webpage_Logo_Ad&utm_content=Developer&utm_campaign=DjangoRESTFramework_Jan2022_HomePage
-[rollbar-url]: https://rollbar.com/?utm_source=django&utm_medium=sponsorship&utm_campaign=freetrial
+[spacinov-url]: https://www.spacinov.com/
-[esg-url]: https://software.esg-usa.com/
 [retool-url]: https://retool.com/?utm_source=djangorest&utm_medium=sponsorship
 [bitio-url]: https://bit.io/jobs?utm_source=DRF&utm_medium=sponsor&utm_campaign=DRF_sponsorship
 [posthog-url]: https://posthog.com?utm_source=drf&utm_medium=sponsorship&utm_campaign=open-source-sponsorship
 [cryptapi-url]: https://cryptapi.io
+[fezto-url]: https://www.fezto.xyz/?utm_source=DjangoRESTFramework
 
 [oauth1-section]: https://www.django-rest-framework.org/api-guide/authentication/#django-rest-framework-oauth
 [oauth2-section]: https://www.django-rest-framework.org/api-guide/authentication/#django-oauth-toolkit

docs/api-guide/authentication.md

@@ -120,6 +120,14 @@ Unauthenticated responses that are denied permission will result in an `HTTP 401
 
 ## TokenAuthentication
 
+---
+
+**Note:** The token authentication provided by Django REST framework is a fairly simple implementation.
+
+For an implementation which allows more than one token per user, has some tighter security implementation details, and supports token expiry, please see the [Django REST Knox][django-rest-knox] third party package.
+
+---
+
 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` scheme you'll need to [configure the authentication classes](#setting-the-authentication-scheme) to include `TokenAuthentication`, and additionally include `rest_framework.authtoken` in your `INSTALLED_APPS` setting:
@@ -129,11 +137,9 @@ To use the `TokenAuthentication` scheme you'll need to [configure the authentica
         'rest_framework.authtoken'
     ]
 
----
+Make sure to run `manage.py migrate` after changing your settings.
 
-**Note:** Make sure to run `manage.py migrate` after changing your settings. The `rest_framework.authtoken` app provides Django database migrations.
+The `rest_framework.authtoken` app provides Django database migrations.
-
----
 
 You'll also need to create tokens for your users.
 
@@ -146,7 +152,7 @@ For clients to authenticate, the token key should be included in the `Authorizat
 
     Authorization: Token 9944b09199c62bcf9418ad846dd0e4bbdfc6ee4b
 
-**Note:** If you want to use a different keyword in the header, such as `Bearer`, simply subclass `TokenAuthentication` and set the `keyword` class variable.
+*If you want to use a different keyword in the header, such as `Bearer`, simply subclass `TokenAuthentication` and set the `keyword` class variable.*
 
 If successfully authenticated, `TokenAuthentication` provides the following credentials.
 
@@ -355,6 +361,10 @@ The following example will authenticate any incoming request as the user given b
 
 The following third-party packages are also available.
 
+## django-rest-knox
+
+[Django-rest-knox][django-rest-knox] library provides models and views to handle token-based authentication in a more secure and extensible way than the built-in TokenAuthentication scheme - with Single Page Applications and Mobile clients in mind. It provides per-client tokens, and views to generate them when provided some other authentication (usually basic authentication), to delete the token (providing a server enforced logout) and to delete all tokens (logs out all clients that a user is logged into).
+
 ## Django OAuth Toolkit
 
 The [Django OAuth Toolkit][django-oauth-toolkit] package provides OAuth 2.0 support and works with Python 3.4+. The package is maintained by [jazzband][jazzband] and uses the excellent [OAuthLib][oauthlib].  The package is well documented, and well supported and is currently our **recommended package for OAuth 2.0 support**.
@@ -424,10 +434,6 @@ There are currently two forks of this project.
 
 [Drf-social-oauth2][drf-social-oauth2] is a framework that helps you authenticate with major social oauth2 vendors, such as Facebook, Google, Twitter, Orcid, etc. It generates tokens in a JWTed way with an easy setup.
 
-## django-rest-knox
-
-[Django-rest-knox][django-rest-knox] library provides models and views to handle token-based authentication in a more secure and extensible way than the built-in TokenAuthentication scheme - with Single Page Applications and Mobile clients in mind. It provides per-client tokens, and views to generate them when provided some other authentication (usually basic authentication), to delete the token (providing a server enforced logout) and to delete all tokens (logs out all clients that a user is logged into).
-
 ## drfpasswordless
 
 [drfpasswordless][drfpasswordless] adds (Medium, Square Cash inspired) passwordless support to Django REST Framework's TokenAuthentication scheme. Users log in and sign up with a token sent to a contact point like an email address or a mobile number.

docs/api-guide/exceptions.md

@@ -260,6 +260,15 @@ Set as `handler400`:
 
     handler400 = 'rest_framework.exceptions.bad_request'
 
+# Third party packages
+
+The following third-party packages are also available.
+
+## DRF Standardized Errors
+
+The [drf-standardized-errors][drf-standardized-errors] package provides an exception handler that generates the same format for all 4xx and 5xx responses. It is a drop-in replacement for the default exception handler and allows customizing the error response format without rewriting the whole exception handler. The standardized error response format is easier to document and easier to handle by API consumers.
+
 [cite]: https://doughellmann.com/blog/2009/06/19/python-exception-handling-techniques/
 [authentication]: authentication.md
 [django-custom-error-views]: https://docs.djangoproject.com/en/dev/topics/http/views/#customizing-error-views
+[drf-standardized-errors]: https://github.com/ghazi-git/drf-standardized-errors

docs/api-guide/fields.md

@@ -42,7 +42,7 @@ Set to false if this field is not required to be present during deserialization.
 
 Setting this to `False` also allows the object attribute or dictionary key to be omitted from output when serializing the instance. If the key is not present it will simply not be included in the output representation.
 
-Defaults to `True`.
+Defaults to `True`. If you're using [Model Serializer](https://www.django-rest-framework.org/api-guide/serializers/#modelserializer) default value will be `False` if you have specified `blank=True` or `default` or `null=True` at your field in your `Model`.
 
 ### `default`
 

docs/api-guide/routers.md

@@ -338,5 +338,5 @@ The [`DRF-extensions` package][drf-extensions] provides [routers][drf-extensions
 [drf-extensions-nested-viewsets]: https://chibisov.github.io/drf-extensions/docs/#nested-routes
 [drf-extensions-collection-level-controllers]: https://chibisov.github.io/drf-extensions/docs/#collection-level-controllers
 [drf-extensions-customizable-endpoint-names]: https://chibisov.github.io/drf-extensions/docs/#controller-endpoint-name
-[url-namespace-docs]: https://docs.djangoproject.com/en/1.11/topics/http/urls/#url-namespaces
+[url-namespace-docs]: https://docs.djangoproject.com/en/4.0/topics/http/urls/#url-namespaces
-[include-api-reference]: https://docs.djangoproject.com/en/2.0/ref/urls/#include
+[include-api-reference]: https://docs.djangoproject.com/en/4.0/ref/urls/#include

docs/api-guide/schemas.md

@@ -165,7 +165,7 @@ In order to customize the top-level schema, subclass
 as an argument to the `generateschema` command or `get_schema_view()` helper
 function.
 
-### get_schema(self, request)
+### get_schema(self, request=None, public=False)
 
 Returns a dictionary that represents the OpenAPI schema:
 
@@ -313,6 +313,11 @@ Computes the component's name from the serializer.
 
 You may see warnings if your API has duplicate component names. If so you can override `get_component_name()` or pass the `component_name` `__init__()` kwarg (see below) to provide different names.
 
+#### `get_reference()`
+
+Returns a reference to the serializer component. This may be useful if you override `get_schema()`.
+
+
 #### `map_serializer()`
 
 Maps serializers to their OpenAPI representations.

docs/community/funding.md

@@ -137,7 +137,7 @@ REST framework continues to be open-source and permissively licensed, but we fir
 ## What future funding will enable
 
 * Realtime API support, using WebSockets. This will consist of documentation and support for using REST framework together with Django Channels, plus integrating WebSocket support into the client libraries.
-* Better authentication defaults, possibly bringing JWT & CORs support into the core package.
+* Better authentication defaults, possibly bringing JWT & CORS support into the core package.
 * Securing the community & operations manager position long-term.
 * Opening up and securing a part-time position to focus on ticket triage and resolution.
 * Paying for development time on building API client libraries in a range of programming languages. These would be integrated directly into the upcoming API documentation.

docs/community/jobs.md

@@ -11,7 +11,7 @@ Looking for a new Django REST Framework related role? On this site we provide a
 * [https://djangojobs.net/jobs/][django-jobs-net]
 * [https://findwork.dev/django-rest-framework-jobs][findwork-dev]
 * [https://www.indeed.com/q-Django-jobs.html][indeed-com]
-* [https://stackoverflow.com/jobs/developer-jobs-using-django][stackoverflow-com]
+* [https://stackoverflow.com/jobs/companies?tl=django][stackoverflow-com]
 * [https://www.upwork.com/o/jobs/browse/skill/django-framework/][upwork-com]
 * [https://www.technojobs.co.uk/django-jobs][technobjobs-co-uk]
 * [https://remoteok.io/remote-django-jobs][remoteok-io]
@@ -29,7 +29,7 @@ Wonder how else you can help? One of the best ways you can help Django REST Fram
 [django-jobs-net]: https://djangojobs.net/jobs/
 [findwork-dev]: https://findwork.dev/django-rest-framework-jobs
 [indeed-com]: https://www.indeed.com/q-Django-jobs.html
-[stackoverflow-com]: https://stackoverflow.com/jobs/developer-jobs-using-django
+[stackoverflow-com]: https://stackoverflow.com/jobs/companies?tl=django
 [upwork-com]: https://www.upwork.com/o/jobs/browse/skill/django-framework/
 [technobjobs-co-uk]: https://www.technojobs.co.uk/django-jobs
 [remoteok-io]: https://remoteok.io/remote-django-jobs

docs/community/third-party-packages.md

@@ -148,6 +148,8 @@ To submit new content, [open an issue][drf-create-issue] or [create a pull reque
 * [django-elasticsearch-dsl-drf][django-elasticsearch-dsl-drf] - Integrate Elasticsearch DSL with Django REST framework. Package provides views, serializers, filter backends, pagination and other handy add-ons.
 * [django-api-client][django-api-client] - DRF client that groups the Endpoint response, for use in CBVs and FBV as if you were working with Django's Native Models..
 * [fast-drf] - A model based library for making API development faster and easier.
+* [django-requestlogs] - Providing middleware and other helpers for audit logging for REST framework.
+* [drf-standardized-errors][drf-standardized-errors] - DRF exception handler to standardize error responses for all API endpoints.
 
 [cite]: http://www.software-ecosystems.com/Software_Ecosystems/Ecosystems.html
 [cookiecutter]: https://github.com/jpadilla/cookiecutter-django-rest-framework
@@ -237,3 +239,5 @@ To submit new content, [open an issue][drf-create-issue] or [create a pull reque
 [graphwrap]: https://github.com/PaulGilmartin/graph_wrap
 [rest-framework-actions]: https://github.com/AlexisMunera98/rest-framework-actions
 [fast-drf]: https://github.com/iashraful/fast-drf
+[django-requestlogs]: https://github.com/Raekkeri/django-requestlogs
+[drf-standardized-errors]: https://github.com/ghazi-git/drf-standardized-errors

docs/index.md

@@ -68,16 +68,16 @@ continued development by **[signing up for a paid plan][funding]**.
 <ul class="premium-promo promo">
     <li><a href="https://getsentry.com/welcome/" style="background-image: url(https://fund-rest-framework.s3.amazonaws.com/sentry130.png)">Sentry</a></li>
     <li><a href="https://getstream.io/?utm_source=DjangoRESTFramework&utm_medium=Webpage_Logo_Ad&utm_content=Developer&utm_campaign=DjangoRESTFramework_Jan2022_HomePage" style="background-image: url(https://fund-rest-framework.s3.amazonaws.com/stream-130.png)">Stream</a></li>
-    <li><a href="https://software.esg-usa.com" style="background-image: url(https://fund-rest-framework.s3.amazonaws.com/esg-new-logo.png)">ESG</a></li>
+    <li><a href="https://www.spacinov.com/" style="background-image: url(https://fund-rest-framework.s3.amazonaws.com/spacinov.png)">Spacinov</a></li>
-    <li><a href="https://rollbar.com" style="background-image: url(https://fund-rest-framework.s3.amazonaws.com/rollbar2.png)">Rollbar</a></li>
     <li><a href="https://retool.com/?utm_source=djangorest&utm_medium=sponsorship" style="background-image: url(https://fund-rest-framework.s3.amazonaws.com/retool-sidebar.png)">Retool</a></li>
     <li><a href="https://bit.io/jobs?utm_source=DRF&utm_medium=sponsor&utm_campaign=DRF_sponsorship" style="background-image: url(https://fund-rest-framework.s3.amazonaws.com/bitio_logo_gold_background.png)">bit.io</a></li>
     <li><a href="https://posthog.com?utm_source=DRF&utm_medium=sponsor&utm_campaign=DRF_sponsorship" style="background-image: url(https://fund-rest-framework.s3.amazonaws.com/135996800-d49fe024-32d9-441a-98d9-4c7596287a67.png)">PostHog</a></li>
     <li><a href="https://cryptapi.io" style="background-image: url(https://fund-rest-framework.s3.amazonaws.com/cryptapi.png)">CryptAPI</a></li>
+    <li><a href="https://www.fezto.xyz/?utm_source=DjangoRESTFramework" style="background-image: url(https://fund-rest-framework.s3.amazonaws.com/fezto.png)">FEZTO</a></li>
 </ul>
 <div style="clear: both; padding-bottom: 20px;"></div>
 
-*Many thanks to all our [wonderful sponsors][sponsors], and in particular to our premium backers, [Sentry](https://getsentry.com/welcome/), [Stream](https://getstream.io/?utm_source=DjangoRESTFramework&utm_medium=Webpage_Logo_Ad&utm_content=Developer&utm_campaign=DjangoRESTFramework_Jan2022_HomePage), [ESG](https://software.esg-usa.com/), [Rollbar](https://rollbar.com/?utm_source=django&utm_medium=sponsorship&utm_campaign=freetrial), [Cadre](https://cadre.com), [Kloudless](https://hubs.ly/H0f30Lf0), [Lights On Software](https://lightsonsoftware.com), [Retool](https://retool.com/?utm_source=djangorest&utm_medium=sponsorship), [bit.io](https://bit.io/jobs?utm_source=DRF&utm_medium=sponsor&utm_campaign=DRF_sponsorship), [PostHog](https://posthog.com?utm_source=DRF&utm_medium=sponsor&utm_campaign=DRF_sponsorship), and [CryptAPI](https://cryptapi.io).*
+*Many thanks to all our [wonderful sponsors][sponsors], and in particular to our premium backers, [Sentry](https://getsentry.com/welcome/), [Stream](https://getstream.io/?utm_source=DjangoRESTFramework&utm_medium=Webpage_Logo_Ad&utm_content=Developer&utm_campaign=DjangoRESTFramework_Jan2022_HomePage), [Spacinov](https://www.spacinov.com/), [Retool](https://retool.com/?utm_source=djangorest&utm_medium=sponsorship), [bit.io](https://bit.io/jobs?utm_source=DRF&utm_medium=sponsor&utm_campaign=DRF_sponsorship), [PostHog](https://posthog.com?utm_source=DRF&utm_medium=sponsor&utm_campaign=DRF_sponsorship), [CryptAPI](https://cryptapi.io), and [FEZTO](https://www.fezto.xyz/?utm_source=DjangoRESTFramework).*
 
 ---
 
@@ -86,7 +86,7 @@ continued development by **[signing up for a paid plan][funding]**.
 REST framework requires the following:
 
 * Python (3.6, 3.7, 3.8, 3.9, 3.10)
-* Django (2.2, 3.0, 3.1, 3.2, 4.0)
+* Django (2.2, 3.0, 3.1, 3.2, 4.0, 4.1)
 
 We **highly recommend** and only officially support the latest patch release of
 each Python and Django series.

docs/tutorial/6-viewsets-and-routers.md

@@ -112,8 +112,8 @@ Here's our re-wired `snippets/urls.py` file.
 
     # Create a router and register our viewsets with it.
     router = DefaultRouter()
-    router.register(r'snippets', views.SnippetViewSet,basename="snippets")
+    router.register(r'snippets', views.SnippetViewSet,basename="snippet")
-    router.register(r'users', views.UserViewSet,basename="users")
+    router.register(r'users', views.UserViewSet,basename="user")
 
     # The API URLs are now determined automatically by the router.
     urlpatterns = [

requirements/requirements-documentation.txt

@@ -1,2 +1,3 @@
 # MkDocs to build our documentation.
 mkdocs>=1.1.2,<1.2
+jinja2>=2.10,<3.1.0 # contextfilter has been renamed

requirements/requirements-optionals.txt

@@ -4,8 +4,7 @@ coreschema==0.0.4
 django-filter>=2.4.0,<3.0
 django-guardian>=2.4.0,<2.5
 inflection==0.5.1
-markdown==3.3;python_version>="3.6"
+markdown==3.3
-markdown==3.2.2;python_version=="3.5"
 psycopg2-binary>=2.8.5,<2.9
-pygments>=2.7.1,<2.8
+pygments==2.12
 pyyaml>=5.3.1,<5.4

rest_framework/compat.py

@@ -2,6 +2,7 @@
 The `compat` module provides support for backwards compatibility with older
 versions of Django/Python, and compatibility wrappers around optional packages.
 """
+import django
 from django.conf import settings
 from django.views.generic import View
 
@@ -152,6 +153,30 @@ else:
         return False
 
 
+if django.VERSION >= (4, 2):
+    # Django 4.2+: use the stock parse_header_parameters function
+    # Note: Django 4.1 also has an implementation of parse_header_parameters
+    #       which is slightly different from the one in 4.2, it needs
+    #       the compatibility shim as well.
+    from django.utils.http import parse_header_parameters
+else:
+    # Django <= 4.1: create a compatibility shim for parse_header_parameters
+    from django.http.multipartparser import parse_header
+
+    def parse_header_parameters(line):
+        # parse_header works with bytes, but parse_header_parameters
+        # works with strings. Call encode to convert the line to bytes.
+        main_value_pair, params = parse_header(line.encode())
+        return main_value_pair, {
+            # parse_header will convert *some* values to string.
+            # parse_header_parameters converts *all* values to string.
+            # Make sure all values are converted by calling decode on
+            # any remaining non-string values.
+            k: v if isinstance(v, str) else v.decode()
+            for k, v in params.items()
+        }
+
+
 # `separators` argument to `json.dumps()` differs between 2.x and 3.x
 # See: https://bugs.python.org/issue22767
 SHORT_SEPARATORS = (',', ':')

rest_framework/fields.py

@@ -27,7 +27,6 @@ from django.utils.duration import duration_string
 from django.utils.encoding import is_protected_type, smart_str
 from django.utils.formats import localize_input, sanitize_separators
 from django.utils.ipv6 import clean_ipv6_address
-from django.utils.timezone import utc
 from django.utils.translation import gettext_lazy as _
 from pytz.exceptions import InvalidTimeError
 
@@ -63,6 +62,9 @@ def is_simple_callable(obj):
     """
     True if the object is a callable that takes no arguments.
     """
+    if not callable(obj):
+        return False
+
     # Bail early since we cannot inspect built-in function signatures.
     if inspect.isbuiltin(obj):
         raise BuiltinSignatureError(
@@ -1177,7 +1179,7 @@ class DateTimeField(Field):
         When `self.default_timezone` is `None`, always return naive datetimes.
         When `self.default_timezone` is not `None`, always return aware datetimes.
         """
-        field_timezone = getattr(self, 'timezone', self.default_timezone())
+        field_timezone = self.timezone if hasattr(self, 'timezone') else self.default_timezone()
 
         if field_timezone is not None:
             if timezone.is_aware(value):
@@ -1190,7 +1192,7 @@ class DateTimeField(Field):
             except InvalidTimeError:
                 self.fail('make_aware', timezone=field_timezone)
         elif (field_timezone is None) and timezone.is_aware(value):
-            return timezone.make_naive(value, utc)
+            return timezone.make_naive(value, datetime.timezone.utc)
         return value
 
     def default_timezone(self):

rest_framework/negotiation.py

@@ -4,7 +4,7 @@ incoming request.  Typically this will be based on the request's Accept header.
 """
 from django.http import Http404
 
-from rest_framework import HTTP_HEADER_ENCODING, exceptions
+from rest_framework import exceptions
 from rest_framework.settings import api_settings
 from rest_framework.utils.mediatypes import (
     _MediaType, media_type_matches, order_by_precedence
@@ -64,9 +64,11 @@ class DefaultContentNegotiation(BaseContentNegotiation):
                             # Accepted media type is 'application/json'
                             full_media_type = ';'.join(
                                 (renderer.media_type,) +
-                                tuple('{}={}'.format(
+                                tuple(
-                                    key, value.decode(HTTP_HEADER_ENCODING))
+                                    '{}={}'.format(key, value)
-                                    for key, value in media_type_wrapper.params.items()))
+                                    for key, value in media_type_wrapper.params.items()
+                                )
+                            )
                             return renderer, full_media_type
                         else:
                             # Eg client requests 'application/json; indent=8'

rest_framework/parsers.py

@@ -5,7 +5,6 @@ They give us a generic way of being able to handle various media types
 on the request, such as form content or json encoded data.
 """
 import codecs
-from urllib import parse
 
 from django.conf import settings
 from django.core.files.uploadhandler import StopFutureHandlers
@@ -13,10 +12,10 @@ from django.http import QueryDict
 from django.http.multipartparser import ChunkIter
 from django.http.multipartparser import \
     MultiPartParser as DjangoMultiPartParser
-from django.http.multipartparser import MultiPartParserError, parse_header
+from django.http.multipartparser import MultiPartParserError
-from django.utils.encoding import force_str
 
 from rest_framework import renderers
+from rest_framework.compat import parse_header_parameters
 from rest_framework.exceptions import ParseError
 from rest_framework.settings import api_settings
 from rest_framework.utils import json
@@ -201,23 +200,10 @@ class FileUploadParser(BaseParser):
 
         try:
             meta = parser_context['request'].META
-            disposition = parse_header(meta['HTTP_CONTENT_DISPOSITION'].encode())
+            disposition, params = parse_header_parameters(meta['HTTP_CONTENT_DISPOSITION'])
-            filename_parm = disposition[1]
+            if 'filename*' in params:
-            if 'filename*' in filename_parm:
+                return params['filename*']
-                return self.get_encoded_filename(filename_parm)
+            else:
-            return force_str(filename_parm['filename'])
+                return params['filename']
         except (AttributeError, KeyError, ValueError):
             pass
-
-    def get_encoded_filename(self, filename_parm):
-        """
-        Handle encoded filenames per RFC6266. See also:
-        https://tools.ietf.org/html/rfc2231#section-4
-        """
-        encoded_filename = force_str(filename_parm['filename*'])
-        try:
-            charset, lang, filename = encoded_filename.split('\'', 2)
-            filename = parse.unquote(filename)
-        except (ValueError, LookupError):
-            filename = force_str(filename_parm['filename'])
-        return filename

rest_framework/relations.py

@@ -10,7 +10,7 @@ from django.utils.encoding import smart_str, uri_to_iri
 from django.utils.translation import gettext_lazy as _
 
 from rest_framework.fields import (
-    Field, empty, get_attribute, is_simple_callable, iter_options
+    Field, SkipField, empty, get_attribute, is_simple_callable, iter_options
 )
 from rest_framework.reverse import reverse
 from rest_framework.settings import api_settings
@@ -535,7 +535,30 @@ class ManyRelatedField(Field):
         if hasattr(instance, 'pk') and instance.pk is None:
             return []
 
+        try:
             relationship = get_attribute(instance, self.source_attrs)
+        except (KeyError, AttributeError) as exc:
+            if self.default is not empty:
+                return self.get_default()
+            if self.allow_null:
+                return None
+            if not self.required:
+                raise SkipField()
+            msg = (
+                'Got {exc_type} when attempting to get a value for field '
+                '`{field}` on serializer `{serializer}`.\nThe serializer '
+                'field might be named incorrectly and not match '
+                'any attribute or key on the `{instance}` instance.\n'
+                'Original exception text was: {exc}.'.format(
+                    exc_type=type(exc).__name__,
+                    field=self.field_name,
+                    serializer=self.parent.__class__.__name__,
+                    instance=instance.__class__.__name__,
+                    exc=exc
+                )
+            )
+            raise type(exc)(msg)
+
         return relationship.all() if hasattr(relationship, 'all') else relationship
 
     def to_representation(self, iterable):

rest_framework/renderers.py

@@ -14,7 +14,6 @@ from django import forms
 from django.conf import settings
 from django.core.exceptions import ImproperlyConfigured
 from django.core.paginator import Page
-from django.http.multipartparser import parse_header
 from django.template import engines, loader
 from django.urls import NoReverseMatch
 from django.utils.html import mark_safe
@@ -22,7 +21,7 @@ from django.utils.html import mark_safe
 from rest_framework import VERSION, exceptions, serializers, status
 from rest_framework.compat import (
     INDENT_SEPARATORS, LONG_SEPARATORS, SHORT_SEPARATORS, coreapi, coreschema,
-    pygments_css, yaml
+    parse_header_parameters, pygments_css, yaml
 )
 from rest_framework.exceptions import ParseError
 from rest_framework.request import is_form_media_type, override_method
@@ -72,7 +71,7 @@ class JSONRenderer(BaseRenderer):
             # If the media type looks like 'application/json; indent=4',
             # then pretty print the result.
             # Note that we coerce `indent=0` into `indent=None`.
-            base_media_type, params = parse_header(accepted_media_type.encode('ascii'))
+            base_media_type, params = parse_header_parameters(accepted_media_type)
             try:
                 return zero_as_none(max(min(int(params['indent']), 8), 0))
             except (KeyError, ValueError, TypeError):

rest_framework/request.py

@@ -14,11 +14,11 @@ from contextlib import contextmanager
 
 from django.conf import settings
 from django.http import HttpRequest, QueryDict
-from django.http.multipartparser import parse_header
 from django.http.request import RawPostDataException
 from django.utils.datastructures import MultiValueDict
 
-from rest_framework import HTTP_HEADER_ENCODING, exceptions
+from rest_framework import exceptions
+from rest_framework.compat import parse_header_parameters
 from rest_framework.settings import api_settings
 
 
@@ -26,7 +26,7 @@ def is_form_media_type(media_type):
     """
     Return True if the media type is a valid form media type.
     """
-    base_media_type, params = parse_header(media_type.encode(HTTP_HEADER_ENCODING))
+    base_media_type, params = parse_header_parameters(media_type)
     return (base_media_type == 'application/x-www-form-urlencoded' or
             base_media_type == 'multipart/form-data')
 

rest_framework/schemas/openapi.py

@@ -637,7 +637,7 @@ class AutoSchema(ViewInspector):
         """
         return self.get_serializer(path, method)
 
-    def _get_reference(self, serializer):
+    def get_reference(self, serializer):
         return {'$ref': '#/components/schemas/{}'.format(self.get_component_name(serializer))}
 
     def get_request_body(self, path, method):
@@ -651,7 +651,7 @@ class AutoSchema(ViewInspector):
         if not isinstance(serializer, serializers.Serializer):
             item_schema = {}
         else:
-            item_schema = self._get_reference(serializer)
+            item_schema = self.get_reference(serializer)
 
         return {
             'content': {
@@ -675,7 +675,7 @@ class AutoSchema(ViewInspector):
         if not isinstance(serializer, serializers.Serializer):
             item_schema = {}
         else:
-            item_schema = self._get_reference(serializer)
+            item_schema = self.get_reference(serializer)
 
         if is_list_view(path, method, self.view):
             response_schema = {
@@ -809,3 +809,11 @@ class AutoSchema(ViewInspector):
             RemovedInDRF314Warning, stacklevel=2
         )
         return self.allows_filters(path, method)
+
+    def _get_reference(self, serializer):
+        warnings.warn(
+            "Method `_get_reference()` has been renamed to `get_reference()`. "
+            "The old name will be removed in DRF v3.14.",
+            RemovedInDRF314Warning, stacklevel=2
+        )
+        return self.get_reference(serializer)

rest_framework/templatetags/rest_framework.py

@@ -218,7 +218,7 @@ def format_value(value):
         return template.render(context)
     elif isinstance(value, str):
         if (
-            (value.startswith('http:') or value.startswith('https:')) and not
+            (value.startswith('http:') or value.startswith('https:') or value.startswith('/')) and not
             re.search(r'\s', value)
         ):
             return mark_safe('<a href="{value}">{value}</a>'.format(value=escape(value)))

rest_framework/throttling.py

@@ -171,7 +171,7 @@ class AnonRateThrottle(SimpleRateThrottle):
     scope = 'anon'
 
     def get_cache_key(self, request, view):
-        if request.user.is_authenticated:
+        if request.user and request.user.is_authenticated:
             return None  # Only throttle unauthenticated requests.
 
         return self.cache_format % {
@@ -191,7 +191,7 @@ class UserRateThrottle(SimpleRateThrottle):
     scope = 'user'
 
     def get_cache_key(self, request, view):
-        if request.user.is_authenticated:
+        if request.user and request.user.is_authenticated:
             ident = request.user.pk
         else:
             ident = self.get_ident(request)
@@ -237,9 +237,9 @@ class ScopedRateThrottle(SimpleRateThrottle):
         If `view.throttle_scope` is not set, don't apply this throttle.
 
         Otherwise generate the unique cache key by concatenating the user id
-        with the '.throttle_scope` property of the view.
+        with the `.throttle_scope` property of the view.
         """
-        if request.user.is_authenticated:
+        if request.user and request.user.is_authenticated:
             ident = request.user.pk
         else:
             ident = self.get_ident(request)

rest_framework/utils/field_mapping.py

@@ -95,6 +95,9 @@ def get_field_kwargs(field_name, model_field):
             (hasattr(models, 'JSONField') and isinstance(model_field, models.JSONField)):
         kwargs['style'] = {'base_template': 'textarea.html'}
 
+    if model_field.null:
+        kwargs['allow_null'] = True
+
     if isinstance(model_field, models.AutoField) or not model_field.editable:
         # If this field is read-only, then return early.
         # Further keyword arguments are not valid.
@@ -104,9 +107,6 @@ def get_field_kwargs(field_name, model_field):
     if model_field.has_default() or model_field.blank or model_field.null:
         kwargs['required'] = False
 
-    if model_field.null:
-        kwargs['allow_null'] = True
-
     if model_field.blank and (isinstance(model_field, (models.CharField, models.TextField))):
         kwargs['allow_blank'] = True
 
@@ -217,15 +217,9 @@ def get_field_kwargs(field_name, model_field):
         ]
 
     if getattr(model_field, 'unique', False):
-        unique_error_message = model_field.error_messages.get('unique', None)
-        if unique_error_message:
-            unique_error_message = unique_error_message % {
-                'model_name': model_field.model._meta.verbose_name,
-                'field_label': model_field.verbose_name
-            }
         validator = UniqueValidator(
             queryset=model_field.model._default_manager,
-            message=unique_error_message)
+            message=get_unique_error_message(model_field))
         validator_kwarg.append(validator)
 
     if validator_kwarg:
@@ -269,6 +263,8 @@ def get_relation_kwargs(field_name, relation_info):
         if not model_field.editable:
             kwargs['read_only'] = True
             kwargs.pop('queryset', None)
+        if model_field.null:
+            kwargs['allow_null'] = True
         if kwargs.get('read_only', False):
             # If this field is read-only, then return early.
             # No further keyword arguments are valid.
@@ -276,12 +272,12 @@ def get_relation_kwargs(field_name, relation_info):
 
         if model_field.has_default() or model_field.blank or model_field.null:
             kwargs['required'] = False
-        if model_field.null:
-            kwargs['allow_null'] = True
         if model_field.validators:
             kwargs['validators'] = model_field.validators
         if getattr(model_field, 'unique', False):
-            validator = UniqueValidator(queryset=model_field.model._default_manager)
+            validator = UniqueValidator(
+                queryset=model_field.model._default_manager,
+                message=get_unique_error_message(model_field))
             kwargs['validators'] = kwargs.get('validators', []) + [validator]
         if to_many and not model_field.blank:
             kwargs['allow_empty'] = False
@@ -300,3 +296,13 @@ def get_url_kwargs(model_field):
     return {
         'view_name': get_detail_view_name(model_field)
     }
+
+
+def get_unique_error_message(model_field):
+    unique_error_message = model_field.error_messages.get('unique', None)
+    if unique_error_message:
+        unique_error_message = unique_error_message % {
+            'model_name': model_field.model._meta.verbose_name,
+            'field_label': model_field.verbose_name
+        }
+    return unique_error_message

rest_framework/utils/mediatypes.py

@@ -3,9 +3,7 @@ Handling of media types, as found in HTTP Content-Type and Accept headers.
 
 See https://www.w3.org/Protocols/rfc2616/rfc2616-sec3.html#sec3.7
 """
-from django.http.multipartparser import parse_header
+from rest_framework.compat import parse_header_parameters
-
-from rest_framework import HTTP_HEADER_ENCODING
 
 
 def media_type_matches(lhs, rhs):
@@ -46,7 +44,7 @@ def order_by_precedence(media_type_lst):
 class _MediaType:
     def __init__(self, media_type_str):
         self.orig = '' if (media_type_str is None) else media_type_str
-        self.full_type, self.params = parse_header(self.orig.encode(HTTP_HEADER_ENCODING))
+        self.full_type, self.params = parse_header_parameters(self.orig)
         self.main_type, sep, self.sub_type = self.full_type.partition('/')
 
     def match(self, other):
@@ -79,5 +77,5 @@ class _MediaType:
     def __str__(self):
         ret = "%s/%s" % (self.main_type, self.sub_type)
         for key, val in self.params.items():
-            ret += "; %s=%s" % (key, val.decode('ascii'))
+            ret += "; %s=%s" % (key, val)
         return ret

setup.py

@@ -94,6 +94,7 @@ setup(
         'Framework :: Django :: 3.1',
         'Framework :: Django :: 3.2',
         'Framework :: Django :: 4.0',
+        'Framework :: Django :: 4.1',
         'Intended Audience :: Developers',
         'License :: OSI Approved :: BSD License',
         'Operating System :: OS Independent',

tests/browsable_api/no_auth_urls.py

@@ -1,7 +1,8 @@
 from django.urls import path
 
-from .views import MockView
+from .views import BasicModelWithUsersViewSet, MockView
 
 urlpatterns = [
     path('', MockView.as_view()),
+    path('basicviewset', BasicModelWithUsersViewSet.as_view({'get': 'list'})),
 ]

tests/browsable_api/serializers.py

@@ -0,0 +1,8 @@
+from rest_framework.serializers import ModelSerializer
+from tests.models import BasicModelWithUsers
+
+
+class BasicSerializer(ModelSerializer):
+    class Meta:
+        model = BasicModelWithUsers
+        fields = '__all__'

tests/browsable_api/test_browsable_api.py

@@ -1,8 +1,35 @@
 from django.contrib.auth.models import User
 from django.test import TestCase, override_settings
 
+from rest_framework.permissions import IsAuthenticated
 from rest_framework.test import APIClient
 
+from .views import BasicModelWithUsersViewSet, OrganizationPermissions
+
+
+@override_settings(ROOT_URLCONF='tests.browsable_api.no_auth_urls')
+class AnonymousUserTests(TestCase):
+    """Tests correct handling of anonymous user request on endpoints with IsAuthenticated permission class."""
+
+    def setUp(self):
+        self.client = APIClient(enforce_csrf_checks=True)
+
+    def tearDown(self):
+        self.client.logout()
+
+    def test_get_raises_typeerror_when_anonymous_user_in_queryset_filter(self):
+        with self.assertRaises(TypeError):
+            self.client.get('/basicviewset')
+
+    def test_get_returns_http_forbidden_when_anonymous_user(self):
+        old_permissions = BasicModelWithUsersViewSet.permission_classes
+        BasicModelWithUsersViewSet.permission_classes = [IsAuthenticated, OrganizationPermissions]
+
+        response = self.client.get('/basicviewset')
+
+        BasicModelWithUsersViewSet.permission_classes = old_permissions
+        self.assertEqual(response.status_code, 403)
+
 
 @override_settings(ROOT_URLCONF='tests.browsable_api.auth_urls')
 class DropdownWithAuthTests(TestCase):

tests/browsable_api/views.py

@@ -1,6 +1,16 @@
 from rest_framework import authentication, renderers
+from rest_framework.permissions import BasePermission
 from rest_framework.response import Response
 from rest_framework.views import APIView
+from rest_framework.viewsets import ModelViewSet
+
+from ..models import BasicModelWithUsers
+from .serializers import BasicSerializer
+
+
+class OrganizationPermissions(BasePermission):
+    def has_object_permission(self, request, view, obj):
+        return request.user.is_staff or (request.user == obj.owner.organization_user.user)
 
 
 class MockView(APIView):
@@ -9,3 +19,15 @@ class MockView(APIView):
 
     def get(self, request):
         return Response({'a': 1, 'b': 2, 'c': 3})
+
+
+class BasicModelWithUsersViewSet(ModelViewSet):
+    queryset = BasicModelWithUsers.objects.all()
+    serializer_class = BasicSerializer
+    permission_classes = [OrganizationPermissions]
+    # permission_classes = [IsAuthenticated, OrganizationPermissions]
+    renderer_classes = (renderers.BrowsableAPIRenderer, renderers.JSONRenderer)
+
+    def get_queryset(self):
+        qs = super().get_queryset().filter(users=self.request.user)
+        return qs

tests/models.py

@@ -1,5 +1,6 @@
 import uuid
 
+from django.contrib.auth.models import User
 from django.db import models
 from django.utils.translation import gettext_lazy as _
 
@@ -33,6 +34,10 @@ class ManyToManySource(RESTFrameworkModel):
     targets = models.ManyToManyField(ManyToManyTarget, related_name='sources')
 
 
+class BasicModelWithUsers(RESTFrameworkModel):
+    users = models.ManyToManyField(User)
+
+
 # ForeignKey
 class ForeignKeyTarget(RESTFrameworkModel):
     name = models.CharField(max_length=100)

tests/test_description.py

@@ -1,5 +1,3 @@
-import sys
-
 import pytest
 from django.test import TestCase
 
@@ -33,7 +31,7 @@ indented
 
 # If markdown is installed we also test it's working
 # (and that our wrapped forces '=' to h2 and '-' to h3)
-MARKDOWN_BASE = """<h2 id="an-example-docstring">an example docstring</h2>
+MARKDOWN_DOCSTRING = """<h2 id="an-example-docstring">an example docstring</h2>
 <ul>
 <li>list</li>
 <li>list</li>
@@ -42,25 +40,8 @@ MARKDOWN_BASE = """<h2 id="an-example-docstring">an example docstring</h2>
 <pre><code>code block
 </code></pre>
 <p>indented</p>
-<h2 id="hash-style-header">hash style header</h2>%s"""
+<h2 id="hash-style-header">hash style header</h2>
-
+<div class="highlight"><pre><span></span><span class="p">[{</span><span class="w"></span><br /><span class="w">    </span><span class="nt">&quot;alpha&quot;</span><span class="p">:</span><span class="w"> </span><span class="mi">1</span><span class="p">,</span><span class="w"></span><br /><span class="w">    </span><span class="nt">&quot;beta&quot;</span><span class="p">:</span><span class="w"> </span><span class="s2">&quot;this is a string&quot;</span><span class="w"></span><br /><span class="p">}]</span><span class="w"></span><br /></pre></div>
-MARKDOWN_gte_33 = """
-<div class="highlight"><pre><span></span><span class="p">[{</span><br />\
-    <span class="nt">&quot;alpha&quot;</span><span class="p">:</span>\
- <span class="mi">1</span><span class="p">,</span><br />\
-    <span class="nt">&quot;beta&quot;</span><span class="p">:</span>\
- <span class="s2">&quot;this is a string&quot;</span><br />\
-<span class="p">}]</span><br /></pre></div>
-<p><br /></p>"""
-
-MARKDOWN_lt_33 = """
-<div class="highlight"><pre><span></span><span class="p">[{</span><br />\
-    <span class="nt">&quot;alpha&quot;</span><span class="p">:</span>\
- <span class="mi">1</span><span class="p">,</span><br />\
-    <span class="nt">&quot;beta&quot;</span><span class="p">:</span>\
- <span class="s2">&quot;this is a string&quot;</span><br />\
-<span class="p">}]</span><br /></pre></div>
-
 <p><br /></p>"""
 
 
@@ -163,11 +144,7 @@ class TestViewNamesAndDescriptions(TestCase):
         """
         Ensure markdown to HTML works as expected.
         """
-        # Markdown 3.3 is only supported on Python 3.6 and higher
+        assert apply_markdown(DESCRIPTION) == MARKDOWN_DOCSTRING
-        if sys.version_info >= (3, 6):
-            assert apply_markdown(DESCRIPTION) == MARKDOWN_BASE % MARKDOWN_gte_33
-        else:
-            assert apply_markdown(DESCRIPTION) == MARKDOWN_BASE % MARKDOWN_lt_33
 
 
 def test_dedent_tabs():

tests/test_encoders.py

@@ -1,15 +1,16 @@
-from datetime import date, datetime, timedelta
+from datetime import date, datetime, timedelta, timezone
 from decimal import Decimal
 from uuid import uuid4
 
 import pytest
 from django.test import TestCase
-from django.utils.timezone import utc
 
 from rest_framework.compat import coreapi
 from rest_framework.utils.encoders import JSONEncoder
 from rest_framework.utils.serializer_helpers import ReturnList
 
+utc = timezone.utc
+
 
 class MockList:
     def tolist(self):

tests/test_fields.py

@@ -9,7 +9,7 @@ import pytz
 from django.core.exceptions import ValidationError as DjangoValidationError
 from django.http import QueryDict
 from django.test import TestCase, override_settings
-from django.utils.timezone import activate, deactivate, override, utc
+from django.utils.timezone import activate, deactivate, override
 
 import rest_framework
 from rest_framework import exceptions, serializers
@@ -17,6 +17,8 @@ from rest_framework.fields import (
     BuiltinSignatureError, DjangoImageField, is_simple_callable
 )
 
+utc = datetime.timezone.utc
+
 # Tests for helper functions.
 # ---------------------------
 
@@ -73,6 +75,10 @@ class TestIsSimpleCallable:
         assert is_simple_callable(valid_vargs_kwargs)
         assert not is_simple_callable(invalid)
 
+    @pytest.mark.parametrize('obj', (True, None, "str", b'bytes', 123, 1.23))
+    def test_not_callable(self, obj):
+        assert not is_simple_callable(obj)
+
     def test_4602_regression(self):
         from django.db import models
 
@@ -1859,9 +1865,9 @@ class TestMultipleChoiceField(FieldValues):
     def test_against_partial_and_full_updates(self):
         field = serializers.MultipleChoiceField(choices=(('a', 'a'), ('b', 'b')))
         field.partial = False
-        assert field.get_value(QueryDict({})) == []
+        assert field.get_value(QueryDict('')) == []
         field.partial = True
-        assert field.get_value(QueryDict({})) == rest_framework.fields.empty
+        assert field.get_value(QueryDict('')) == rest_framework.fields.empty
 
 
 class TestEmptyMultipleChoiceField(FieldValues):

tests/test_model_serializer.py

@@ -12,6 +12,7 @@ import sys
 import tempfile
 from collections import OrderedDict
 
+import django
 import pytest
 from django.core.exceptions import ImproperlyConfigured
 from django.core.serializers.json import DjangoJSONEncoder
@@ -452,11 +453,14 @@ class TestPosgresFieldsMapping(TestCase):
                 model = ArrayFieldModel
                 fields = ['array_field', 'array_field_with_blank']
 
+        validators = ""
+        if django.VERSION < (4, 1):
+            validators = ", validators=[<django.core.validators.MaxLengthValidator object>]"
         expected = dedent("""
             TestSerializer():
-                array_field = ListField(allow_empty=False, child=CharField(label='Array field', validators=[<django.core.validators.MaxLengthValidator object>]))
+                array_field = ListField(allow_empty=False, child=CharField(label='Array field'%s))
-                array_field_with_blank = ListField(child=CharField(label='Array field with blank', validators=[<django.core.validators.MaxLengthValidator object>]), required=False)
+                array_field_with_blank = ListField(child=CharField(label='Array field with blank'%s), required=False)
-        """)
+        """ % (validators, validators))
         self.assertEqual(repr(TestSerializer()), expected)
 
     @pytest.mark.skipif(hasattr(models, 'JSONField'), reason='has models.JSONField')
@@ -1021,6 +1025,73 @@ class Issue2704TestCase(TestCase):
         assert serializer.data == expected
 
 
+class Issue7550FooModel(models.Model):
+    text = models.CharField(max_length=100)
+    bar = models.ForeignKey(
+        'Issue7550BarModel', null=True, blank=True, on_delete=models.SET_NULL,
+        related_name='foos', related_query_name='foo')
+
+
+class Issue7550BarModel(models.Model):
+    pass
+
+
+class Issue7550TestCase(TestCase):
+
+    def test_dotted_source(self):
+
+        class _FooSerializer(serializers.ModelSerializer):
+            class Meta:
+                model = Issue7550FooModel
+                fields = ('id', 'text')
+
+        class FooSerializer(serializers.ModelSerializer):
+            other_foos = _FooSerializer(source='bar.foos', many=True)
+
+            class Meta:
+                model = Issue7550BarModel
+                fields = ('id', 'other_foos')
+
+        bar = Issue7550BarModel.objects.create()
+        foo_a = Issue7550FooModel.objects.create(bar=bar, text='abc')
+        foo_b = Issue7550FooModel.objects.create(bar=bar, text='123')
+
+        assert FooSerializer(foo_a).data == {
+            'id': foo_a.id,
+            'other_foos': [
+                {
+                    'id': foo_a.id,
+                    'text': foo_a.text,
+                },
+                {
+                    'id': foo_b.id,
+                    'text': foo_b.text,
+                },
+            ],
+        }
+
+    def test_dotted_source_with_default(self):
+
+        class _FooSerializer(serializers.ModelSerializer):
+            class Meta:
+                model = Issue7550FooModel
+                fields = ('id', 'text')
+
+        class FooSerializer(serializers.ModelSerializer):
+            other_foos = _FooSerializer(source='bar.foos', default=[], many=True)
+
+            class Meta:
+                model = Issue7550FooModel
+                fields = ('id', 'other_foos')
+
+        foo = Issue7550FooModel.objects.create(bar=None, text='abc')
+
+        assert FooSerializer(foo).data == {
+            'id': foo.id,
+            'other_foos': [],
+        }
+
+
 class DecimalFieldModel(models.Model):
     decimal_field = models.DecimalField(
         max_digits=3,

tests/test_validators.py

@@ -42,6 +42,12 @@ class RelatedModelSerializer(serializers.ModelSerializer):
         fields = ('username', 'email')
 
 
+class RelatedModelUserSerializer(serializers.ModelSerializer):
+    class Meta:
+        model = RelatedModel
+        fields = ('user',)
+
+
 class AnotherUniquenessModel(models.Model):
     code = models.IntegerField(unique=True)
 
@@ -83,6 +89,13 @@ class TestUniquenessValidation(TestCase):
         assert not serializer.is_valid()
         assert serializer.errors == {'username': ['uniqueness model with this username already exists.']}
 
+    def test_relation_is_not_unique(self):
+        RelatedModel.objects.create(user=self.instance)
+        data = {'user': self.instance.pk}
+        serializer = RelatedModelUserSerializer(data=data)
+        assert not serializer.is_valid()
+        assert serializer.errors == {'user': ['related model with this user already exists.']}
+
     def test_is_unique(self):
         data = {'username': 'other'}
         serializer = UniquenessSerializer(data=data)

tox.ini

@@ -3,7 +3,7 @@ envlist =
        {py36,py37,py38,py39}-django22,
        {py36,py37,py38,py39}-django31,
        {py36,py37,py38,py39,py310}-django32,
-       {py38,py39,py310}-{django40,djangomain},
+       {py38,py39,py310}-{django40,django41,djangomain},
        base,dist,docs,
 
 [travis:env]
@@ -12,6 +12,7 @@ DJANGO =
     3.1: django31
     3.2: django32
     4.0: django40
+    4.1: django41
     main: djangomain
 
 [testenv]
@@ -24,7 +25,8 @@ deps =
         django22: Django>=2.2,<3.0
         django31: Django>=3.1,<3.2
         django32: Django>=3.2,<4.0
-        django40: Django>=4.0,<5.0
+        django40: Django>=4.0,<4.1
+        django41: Django>=4.1a1,<4.2
         djangomain: https://github.com/django/django/archive/main.tar.gz
         -rrequirements/requirements-testing.txt
         -rrequirements/requirements-optionals.txt