Django rest framework recursive support (#110)

* add get_serializer_ref_name utility function
* implement RecursiveFieldInspector
* add option to allow non-existing reference in SchemaRef
* add examples and README
* Update changelog and docs

README.rst

@@ -353,6 +353,12 @@ Integration with `djangorestframework-camel-case <https://github.com/vbabiy/djan
 provided out of the box - if you have ``djangorestframework-camel-case`` installed and your ``APIView`` uses
 ``CamelCaseJSONParser`` or ``CamelCaseJSONRenderer``, all property names will be converted to *camelCase* by default.
 
+djangorestframework-recursive
+===============================
+
+Integration with `djangorestframework-recursive <https://github.com/heywbj/django-rest-framework-recursive>`_ is
+provided out of the box - if you have ``djangorestframework-recursive`` installed.
+
 .. |travis| image:: https://img.shields.io/travis/axnsan12/drf-yasg/master.svg
    :target: https://travis-ci.org/axnsan12/drf-yasg
    :alt: Travis CI

docs/changelog.rst

@@ -3,6 +3,20 @@ Changelog
 #########
 
 
+*********
+**1.7.0**
+*********
+
+*Release date: Apr 27, 2018*
+
+- **ADDED:** added integration with `djangorestframework-recursive <https://github.com/heywbj/django-rest-framework-recursive>`_
+  (:issue:`109`, :pr:`110`, thanks to :ghuser:`rsichny`)
+
+  *NOTE:* in order for this to work, you will have to add the new ``drf_yasg.inspectors.RecursiveFieldInspector`` to
+  your ``DEFAULT_FIELD_INSPECTORS`` array if you changed it from the default value
+
+- **FIXED:** ``SchemaRef`` now supports cyclical references via the ``ignore_unresolved`` argument
+
 *********
 **1.6.2**
 *********

docs/settings.rst

@@ -67,6 +67,7 @@ to this list.
 :class:`'drf_yasg.inspectors.FileFieldInspector' <.inspectors.FileFieldInspector>`, |br| \
 :class:`'drf_yasg.inspectors.DictFieldInspector' <.inspectors.DictFieldInspector>`, |br| \
 :class:`'drf_yasg.inspectors.HiddenFieldInspector' <.inspectors.HiddenFieldInspector>`, |br| \
+:class:`'drf_yasg.inspectors.RecursiveFieldInspector' <.inspectors.RecursiveFieldInspector>`, |br| \
 :class:`'drf_yasg.inspectors.SimpleFieldInspector' <.inspectors.SimpleFieldInspector>`, |br| \
 :class:`'drf_yasg.inspectors.StringDefaultFieldInspector' <.inspectors.StringDefaultFieldInspector>`, |br| \
 ``]``

requirements/testproj.txt

@@ -5,5 +5,6 @@ django-cors-headers>=2.1.0
 django-filter>=1.1.0,<2.0; python_version == "2.7"
 django-filter>=1.1.0; python_version >= "3.4"
 djangorestframework-camel-case>=0.2.0
+djangorestframework-recursive>=0.1.2
 dj-database-url>=0.4.2
 user_agents>=1.1.0

src/drf_yasg/app_settings.py

@@ -6,12 +6,13 @@ SWAGGER_DEFAULTS = {
 
     'DEFAULT_FIELD_INSPECTORS': [
         'drf_yasg.inspectors.CamelCaseJSONFilter',
+        'drf_yasg.inspectors.RecursiveFieldInspector',
         'drf_yasg.inspectors.ReferencingSerializerInspector',
-        'drf_yasg.inspectors.RelatedFieldInspector',
         'drf_yasg.inspectors.ChoiceFieldInspector',
         'drf_yasg.inspectors.FileFieldInspector',
         'drf_yasg.inspectors.DictFieldInspector',
         'drf_yasg.inspectors.HiddenFieldInspector',
+        'drf_yasg.inspectors.RelatedFieldInspector',
         'drf_yasg.inspectors.SimpleFieldInspector',
         'drf_yasg.inspectors.StringDefaultFieldInspector',
     ],

src/drf_yasg/inspectors/__init__.py

@@ -4,8 +4,8 @@ from .base import (
 )
 from .field import (
     CamelCaseJSONFilter, ChoiceFieldInspector, DictFieldInspector, FileFieldInspector, HiddenFieldInspector,
-    InlineSerializerInspector, ReferencingSerializerInspector, RelatedFieldInspector, SimpleFieldInspector,
+    InlineSerializerInspector, RecursiveFieldInspector, ReferencingSerializerInspector, RelatedFieldInspector,
-    StringDefaultFieldInspector
+    SimpleFieldInspector, StringDefaultFieldInspector
 )
 from .query import CoreAPICompatInspector, DjangoRestResponsePagination
 from .view import SwaggerAutoSchema
@@ -23,9 +23,9 @@ __all__ = [
     'CoreAPICompatInspector', 'DjangoRestResponsePagination',
 
     # field inspectors
-    'InlineSerializerInspector', 'ReferencingSerializerInspector', 'RelatedFieldInspector', 'SimpleFieldInspector',
+    'InlineSerializerInspector', 'RecursiveFieldInspector', 'ReferencingSerializerInspector', 'RelatedFieldInspector',
-    'FileFieldInspector', 'ChoiceFieldInspector', 'DictFieldInspector', 'StringDefaultFieldInspector',
+    'SimpleFieldInspector', 'FileFieldInspector', 'ChoiceFieldInspector', 'DictFieldInspector',
-    'CamelCaseJSONFilter', 'HiddenFieldInspector',
+    'StringDefaultFieldInspector', 'CamelCaseJSONFilter', 'HiddenFieldInspector',
 
     # view inspectors
     'SwaggerAutoSchema',

src/drf_yasg/inspectors/field.py

@@ -10,7 +10,7 @@ from rest_framework.settings import api_settings as rest_framework_settings
 
 from .. import openapi
 from ..errors import SwaggerGenerationError
-from ..utils import decimal_as_float, filter_none
+from ..utils import decimal_as_float, filter_none, get_serializer_ref_name
 from .base import FieldInspector, NotHandled, SerializerInspector
 
 logger = logging.getLogger(__name__)
@@ -55,23 +55,12 @@ class InlineSerializerInspector(SerializerInspector):
             if swagger_object_type != openapi.Schema:
                 raise SwaggerGenerationError("cannot instantiate nested serializer as " + swagger_object_type.__name__)
 
-            serializer = field
+            ref_name = get_serializer_ref_name(field)
-            serializer_meta = getattr(serializer, 'Meta', None)
-            serializer_name = type(serializer).__name__
-            if hasattr(serializer_meta, 'ref_name'):
-                ref_name = serializer_meta.ref_name
-            elif serializer_name == 'NestedSerializer' and isinstance(serializer, serializers.ModelSerializer):
-                logger.debug("Forcing inline output for ModelSerializer named 'NestedSerializer': " + str(serializer))
-                ref_name = None
-            else:
-                ref_name = serializer_name
-                if ref_name.endswith('Serializer'):
-                    ref_name = ref_name[:-len('Serializer')]
 
             def make_schema_definition():
                 properties = OrderedDict()
                 required = []
-                for property_name, child in serializer.fields.items():
+                for property_name, child in field.fields.items():
                     property_name = self.get_property_name(property_name)
                     prop_kwargs = {
                         'read_only': child.read_only or None
@@ -531,3 +520,24 @@ else:
                 return camelize_schema(result, self.components)
 
             return result
+
+try:
+    from rest_framework_recursive.fields import RecursiveField
+except ImportError:
+    class RecursiveFieldInspector(FieldInspector):
+        """Provides conversion for RecursiveField (https://github.com/heywbj/django-rest-framework-recursive)"""
+        pass
+else:
+    class RecursiveFieldInspector(FieldInspector):
+        """Provides conversion for RecursiveField (https://github.com/heywbj/django-rest-framework-recursive)"""
+        def field_to_swagger_object(self, field, swagger_object_type, use_references, **kwargs):
+            if isinstance(field, RecursiveField) and swagger_object_type == openapi.Schema:
+                assert use_references is True, "Can not create schema for RecursiveField when use_references is False"
+
+                ref_name = get_serializer_ref_name(field.proxied)
+                assert ref_name is not None, "Can not create RecursiveField schema for inline ModelSerializer"
+
+                return openapi.SchemaRef(self.components.with_scope(openapi.SCHEMA_DEFINITIONS), ref_name,
+                                         ignore_unresolved=True)
+
+            return NotHandled

src/drf_yasg/openapi.py

@@ -466,7 +466,7 @@ class Schema(SwaggerDict):
 class _Ref(SwaggerDict):
     ref_name_re = re.compile(r"#/(?P<scope>.+)/(?P<name>[^/]+)$")
 
-    def __init__(self, resolver, name, scope, expected_type):
+    def __init__(self, resolver, name, scope, expected_type, ignore_unresolved=False):
         """Base class for all reference types. A reference object has only one property, ``$ref``, which must be a JSON
         reference to a valid object in the specification, e.g. ``#/definitions/Article`` to refer to an article model.
 
@@ -474,13 +474,15 @@ class _Ref(SwaggerDict):
         :param str name: referenced object name, e.g. "Article"
         :param str scope: reference scope, e.g. "definitions"
         :param type[.SwaggerDict] expected_type: the expected type that will be asserted on the object found in resolver
+        :param bool ignore_unresolved: allow the reference to be not defined in resolver
         """
         super(_Ref, self).__init__()
         assert not type(self) == _Ref, "do not instantiate _Ref directly"
         ref_name = "#/{scope}/{name}".format(scope=scope, name=name)
-        obj = resolver.get(name, scope)
+        if not ignore_unresolved:
-        assert isinstance(obj, expected_type), ref_name + " is a {actual}, not a {expected}" \
+            obj = resolver.get(name, scope)
-            .format(actual=type(obj).__name__, expected=expected_type.__name__)
+            assert isinstance(obj, expected_type), ref_name + " is a {actual}, not a {expected}" \
+                .format(actual=type(obj).__name__, expected=expected_type.__name__)
         self.ref = ref_name
 
     def resolve(self, resolver):
@@ -502,14 +504,15 @@ class _Ref(SwaggerDict):
 
 
 class SchemaRef(_Ref):
-    def __init__(self, resolver, schema_name):
+    def __init__(self, resolver, schema_name, ignore_unresolved=False):
         """Adds a reference to a named Schema defined in the ``#/definitions/`` object.
 
         :param .ReferenceResolver resolver: component resolver which must contain the definition
         :param str schema_name: schema name
+        :param bool ignore_unresolved: allow the reference to be not defined in resolver
         """
         assert SCHEMA_DEFINITIONS in resolver.scopes
-        super(SchemaRef, self).__init__(resolver, schema_name, SCHEMA_DEFINITIONS, Schema)
+        super(SchemaRef, self).__init__(resolver, schema_name, SCHEMA_DEFINITIONS, Schema, ignore_unresolved)
 
 
 Schema.OR_REF = (Schema, SchemaRef)

src/drf_yasg/utils.py

@@ -295,3 +295,25 @@ def decimal_as_float(field):
     if isinstance(field, serializers.DecimalField) or isinstance(field, models.DecimalField):
         return not getattr(field, 'coerce_to_string', rest_framework_settings.COERCE_DECIMAL_TO_STRING)
     return False
+
+
+def get_serializer_ref_name(serializer):
+    """
+    Get serializer's ref_name (or None for ModelSerializer if it is named 'NestedSerializer')
+
+    :param serializer: Serializer instance
+    :return: Serializer's ref_name or None for inline serializer
+    :rtype: str or None
+    """
+    serializer_meta = getattr(serializer, 'Meta', None)
+    serializer_name = type(serializer).__name__
+    if hasattr(serializer_meta, 'ref_name'):
+        ref_name = serializer_meta.ref_name
+    elif serializer_name == 'NestedSerializer' and isinstance(serializer, serializers.ModelSerializer):
+        logger.debug("Forcing inline output for ModelSerializer named 'NestedSerializer': " + str(serializer))
+        ref_name = None
+    else:
+        ref_name = serializer_name
+        if ref_name.endswith('Serializer'):
+            ref_name = ref_name[:-len('Serializer')]
+    return ref_name

testproj/todo/migrations/0002_todotree.py

@@ -0,0 +1,22 @@
+# Generated by Django 2.0.4 on 2018-04-26 13:06
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+    dependencies = [
+        ('todo', '0001_initial'),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name='TodoTree',
+            fields=[
+                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('title', models.CharField(max_length=50)),
+                ('parent', models.ForeignKey(null=True, on_delete=django.db.models.deletion.CASCADE,
+                                             related_name='children', to='todo.TodoTree')),
+            ],
+        ),
+    ]

testproj/todo/models.py

@@ -13,3 +13,8 @@ class TodoAnother(models.Model):
 class TodoYetAnother(models.Model):
     todo = models.ForeignKey(TodoAnother, on_delete=models.CASCADE)
     title = models.CharField(max_length=50)
+
+
+class TodoTree(models.Model):
+    parent = models.ForeignKey('self', on_delete=models.CASCADE, related_name='children', null=True)
+    title = models.CharField(max_length=50)

testproj/todo/serializer.py

@@ -1,7 +1,8 @@
 from django.utils import timezone
 from rest_framework import serializers
+from rest_framework_recursive.fields import RecursiveField
 
-from .models import Todo, TodoAnother, TodoYetAnother
+from .models import Todo, TodoAnother, TodoTree, TodoYetAnother
 
 
 class TodoSerializer(serializers.ModelSerializer):
@@ -25,3 +26,22 @@ class TodoYetAnotherSerializer(serializers.ModelSerializer):
         model = TodoYetAnother
         fields = ('title', 'todo')
         depth = 2
+
+
+class TodoTreeSerializer(serializers.ModelSerializer):
+    children = serializers.ListField(child=RecursiveField(), source='children.all')
+
+    class Meta:
+        model = TodoTree
+        fields = ('id', 'title', 'children')
+
+
+class TodoRecursiveSerializer(serializers.ModelSerializer):
+    parent = RecursiveField(read_only=True)
+    parent_id = serializers.PrimaryKeyRelatedField(queryset=TodoTree.objects.all(), pk_field=serializers.IntegerField(),
+                                                   write_only=True, allow_null=True, required=False, default=None,
+                                                   source='parent')
+
+    class Meta:
+        model = TodoTree
+        fields = ('id', 'title', 'parent', 'parent_id')

testproj/todo/urls.py

@@ -7,10 +7,12 @@ router = routers.DefaultRouter()
 router.register(r'', views.TodoViewSet)
 router.register(r'another', views.TodoAnotherViewSet)
 router.register(r'yetanother', views.TodoYetAnotherViewSet)
+router.register(r'tree', views.TodoTreeView)
+router.register(r'recursive', views.TodoRecursiveView)
 
 urlpatterns = router.urls
 
 urlpatterns += [
     url(r'^(?P<todo_id>\d+)/yetanother/(?P<yetanother_id>\d+)/$',
-        views.NestedTodoView.as_view(),),
+        views.NestedTodoView.as_view(), ),
 ]

testproj/todo/views.py

@@ -1,8 +1,10 @@
 from rest_framework import viewsets
 from rest_framework.generics import RetrieveAPIView
 
-from .models import Todo, TodoAnother, TodoYetAnother
+from .models import Todo, TodoAnother, TodoTree, TodoYetAnother
-from .serializer import TodoAnotherSerializer, TodoSerializer, TodoYetAnotherSerializer
+from .serializer import (
+    TodoAnotherSerializer, TodoRecursiveSerializer, TodoSerializer, TodoTreeSerializer, TodoYetAnotherSerializer
+)
 
 
 class TodoViewSet(viewsets.ReadOnlyModelViewSet):
@@ -25,3 +27,13 @@ class TodoYetAnotherViewSet(viewsets.ReadOnlyModelViewSet):
 
 class NestedTodoView(RetrieveAPIView):
     serializer_class = TodoYetAnotherSerializer
+
+
+class TodoTreeView(viewsets.ReadOnlyModelViewSet):
+    queryset = TodoTree.objects.all()
+    serializer_class = TodoTreeSerializer
+
+
+class TodoRecursiveView(viewsets.ModelViewSet):
+    queryset = TodoTree.objects.all()
+    serializer_class = TodoRecursiveSerializer

tests/reference.yaml

@@ -495,6 +495,129 @@ paths:
         description: A unique integer value identifying this todo another.
         required: true
         type: integer
+  /todo/recursive/:
+    get:
+      operationId: todo_recursive_list
+      description: ''
+      parameters: []
+      responses:
+        '200':
+          description: ''
+          schema:
+            type: array
+            items:
+              $ref: '#/definitions/TodoRecursive'
+      tags:
+        - todo
+    post:
+      operationId: todo_recursive_create
+      description: ''
+      parameters:
+        - name: data
+          in: body
+          required: true
+          schema:
+            $ref: '#/definitions/TodoRecursive'
+      responses:
+        '201':
+          description: ''
+          schema:
+            $ref: '#/definitions/TodoRecursive'
+      tags:
+        - todo
+    parameters: []
+  /todo/recursive/{id}/:
+    get:
+      operationId: todo_recursive_read
+      description: ''
+      parameters: []
+      responses:
+        '200':
+          description: ''
+          schema:
+            $ref: '#/definitions/TodoRecursive'
+      tags:
+        - todo
+    put:
+      operationId: todo_recursive_update
+      description: ''
+      parameters:
+        - name: data
+          in: body
+          required: true
+          schema:
+            $ref: '#/definitions/TodoRecursive'
+      responses:
+        '200':
+          description: ''
+          schema:
+            $ref: '#/definitions/TodoRecursive'
+      tags:
+        - todo
+    patch:
+      operationId: todo_recursive_partial_update
+      description: ''
+      parameters:
+        - name: data
+          in: body
+          required: true
+          schema:
+            $ref: '#/definitions/TodoRecursive'
+      responses:
+        '200':
+          description: ''
+          schema:
+            $ref: '#/definitions/TodoRecursive'
+      tags:
+        - todo
+    delete:
+      operationId: todo_recursive_delete
+      description: ''
+      parameters: []
+      responses:
+        '204':
+          description: ''
+      tags:
+        - todo
+    parameters:
+      - name: id
+        in: path
+        description: A unique integer value identifying this todo tree.
+        required: true
+        type: integer
+  /todo/tree/:
+    get:
+      operationId: todo_tree_list
+      description: ''
+      parameters: []
+      responses:
+        '200':
+          description: ''
+          schema:
+            type: array
+            items:
+              $ref: '#/definitions/TodoTree'
+      tags:
+        - todo
+    parameters: []
+  /todo/tree/{id}/:
+    get:
+      operationId: todo_tree_read
+      description: ''
+      parameters: []
+      responses:
+        '200':
+          description: ''
+          schema:
+            $ref: '#/definitions/TodoTree'
+      tags:
+        - todo
+    parameters:
+      - name: id
+        in: path
+        description: A unique integer value identifying this todo tree.
+        required: true
+        type: integer
   /todo/yetanother/:
     get:
       operationId: todo_yetanother_list
@@ -1337,6 +1460,42 @@ definitions:
         maxLength: 50
       todo:
         $ref: '#/definitions/Todo'
+  TodoRecursive:
+    required:
+      - title
+    type: object
+    properties:
+      id:
+        title: ID
+        type: integer
+        readOnly: true
+      title:
+        title: Title
+        type: string
+        maxLength: 50
+      parent:
+        $ref: '#/definitions/TodoRecursive'
+      parent_id:
+        type: integer
+        title: Parent id
+  TodoTree:
+    required:
+      - title
+      - children
+    type: object
+    properties:
+      id:
+        title: ID
+        type: integer
+        readOnly: true
+      title:
+        title: Title
+        type: string
+        maxLength: 50
+      children:
+        type: array
+        items:
+          $ref: '#/definitions/TodoTree'
   TodoYetAnother:
     required:
       - title

tox.ini

@@ -65,7 +65,7 @@ known_standard_library =
     collections,copy,distutils,functools,inspect,io,json,logging,operator,os,pkg_resources,re,setuptools,sys,
     types,warnings
 known_third_party =
-    coreapi,coreschema,datadiff,dj_database_url,django,django_filters,djangorestframework_camel_case,flex,gunicorn,
+    coreapi,coreschema,datadiff,dj_database_url,django,django_filters,djangorestframework_camel_case,
-    inflection,pygments,pytest,rest_framework,ruamel,setuptools_scm,swagger_spec_validator,uritemplate,user_agents,
+    rest_framework_recursive,flex,gunicorn,inflection,pygments,pytest,rest_framework,ruamel,setuptools_scm,
-    whitenoise
+    swagger_spec_validator,uritemplate,user_agents,whitenoise
 known_first_party = drf_yasg,testproj,articles,people,snippets,todo,users,urlconfs