Added OpenAPI Schema Generation.

rest_framework/filters.py

@@ -40,6 +40,9 @@ class BaseFilterBackend(object):
         assert coreschema is not None, 'coreschema must be installed to use `get_schema_fields()`'
         return []
 
+    def get_schema_operation_parameters(self, view):
+        return []
+
 
 class SearchFilter(BaseFilterBackend):
     # The URL query parameter used for the search.
@@ -159,6 +162,19 @@ class SearchFilter(BaseFilterBackend):
             )
         ]
 
+    def get_schema_operation_parameters(self, view):
+        return [
+            {
+                'name': self.search_param,
+                'required': False,
+                'in': 'query',
+                'description': force_text(self.search_description),
+                'schema': {
+                    'type': 'string',
+                },
+            },
+        ]
+
 
 class OrderingFilter(BaseFilterBackend):
     # The URL query parameter used for the ordering.
@@ -290,6 +306,19 @@ class OrderingFilter(BaseFilterBackend):
             )
         ]
 
+    def get_schema_operation_parameters(self, view):
+        return [
+            {
+                'name': self.ordering_param,
+                'required': False,
+                'in': 'query',
+                'description': force_text(self.ordering_description),
+                'schema': {
+                    'type': 'string',
+                },
+            },
+        ]
+
 
 class DjangoObjectPermissionsFilter(BaseFilterBackend):
     """

rest_framework/management/commands/generateschema.py

@@ -1,25 +1,21 @@
 from django.core.management.base import BaseCommand
 
-from rest_framework.compat import coreapi
-from rest_framework.renderers import (
-    CoreJSONRenderer, JSONOpenAPIRenderer, OpenAPIRenderer
-)
-from rest_framework.schemas.generators import SchemaGenerator
+from rest_framework.compat import yaml
+from rest_framework.schemas.generators import OpenAPISchemaGenerator
+from rest_framework.utils import json
 
 
 class Command(BaseCommand):
     help = "Generates configured API schema for project."
 
     def add_arguments(self, parser):
-        parser.add_argument('--title', dest="title", default=None, type=str)
+        parser.add_argument('--title', dest="title", default='', type=str)
         parser.add_argument('--url', dest="url", default=None, type=str)
         parser.add_argument('--description', dest="description", default=None, type=str)
-        parser.add_argument('--format', dest="format", choices=['openapi', 'openapi-json', 'corejson'], default='openapi', type=str)
+        parser.add_argument('--format', dest="format", choices=['openapi', 'openapi-json'], default='openapi', type=str)
 
     def handle(self, *args, **options):
-        assert coreapi is not None, 'coreapi must be installed.'
-
-        generator = SchemaGenerator(
+        generator = OpenAPISchemaGenerator(
             url=options['url'],
             title=options['title'],
             description=options['description']
@@ -27,15 +23,10 @@ class Command(BaseCommand):
 
         schema = generator.get_schema(request=None, public=True)
 
-        renderer = self.get_renderer(options['format'])
-        output = renderer.render(schema, renderer_context={})
-        self.stdout.write(output.decode('utf-8'))
+        # TODO: Handle via renderer? More options?
+        if options['format'] == 'openapi':
+            output = yaml.dump(schema, default_flow_style=False)
+        else:
+            output = json.dumps(schema, indent=2)
 
-    def get_renderer(self, format):
-        renderer_cls = {
-            'corejson': CoreJSONRenderer,
-            'openapi': OpenAPIRenderer,
-            'openapi-json': JSONOpenAPIRenderer,
-        }[format]
-
-        return renderer_cls()
+        self.stdout.write(output)

rest_framework/pagination.py

@@ -152,6 +152,9 @@ class BasePagination(object):
         assert coreapi is not None, 'coreapi must be installed to use `get_schema_fields()`'
         return []
 
+    def get_schema_operation_parameters(self, view):
+        return []
+
 
 class PageNumberPagination(BasePagination):
     """
@@ -305,6 +308,32 @@ class PageNumberPagination(BasePagination):
             )
         return fields
 
+    def get_schema_operation_parameters(self, view):
+        parameters = [
+            {
+                'name': self.page_query_param,
+                'required': False,
+                'in': 'query',
+                'description': force_text(self.page_query_description),
+                'schema': {
+                    'type': 'integer',
+                },
+            },
+        ]
+        if self.page_size_query_param is not None:
+            parameters.append(
+                {
+                    'name': self.page_size_query_param,
+                    'required': False,
+                    'in': 'query',
+                    'description': force_text(self.page_size_query_description),
+                    'schema': {
+                        'type': 'integer',
+                    },
+                },
+            )
+        return parameters
+
 
 class LimitOffsetPagination(BasePagination):
     """
@@ -434,6 +463,15 @@ class LimitOffsetPagination(BasePagination):
         context = self.get_html_context()
         return template.render(context)
 
+    def get_count(self, queryset):
+        """
+        Determine an object count, supporting either querysets or regular lists.
+        """
+        try:
+            return queryset.count()
+        except (AttributeError, TypeError):
+            return len(queryset)
+
     def get_schema_fields(self, view):
         assert coreapi is not None, 'coreapi must be installed to use `get_schema_fields()`'
         assert coreschema is not None, 'coreschema must be installed to use `get_schema_fields()`'
@@ -458,14 +496,28 @@ class LimitOffsetPagination(BasePagination):
             )
         ]
 
-    def get_count(self, queryset):
-        """
-        Determine an object count, supporting either querysets or regular lists.
-        """
-        try:
-            return queryset.count()
-        except (AttributeError, TypeError):
-            return len(queryset)
+    def get_schema_operation_parameters(self, view):
+        parameters = [
+            {
+                'name': self.limit_query_param,
+                'required': False,
+                'in': 'query',
+                'description': force_text(self.limit_query_description),
+                'schema': {
+                    'type': 'integer',
+                },
+            },
+            {
+                'name': self.offset_query_param,
+                'required': False,
+                'in': 'query',
+                'description': force_text(self.offset_query_description),
+                'schema': {
+                    'type': 'integer',
+                },
+            },
+        ]
+        return parameters
 
 
 class CursorPagination(BasePagination):
@@ -820,3 +872,29 @@ class CursorPagination(BasePagination):
                 )
             )
         return fields
+
+    def get_schema_operation_parameters(self, view):
+        parameters = [
+            {
+                'name': self.cursor_query_param,
+                'required': False,
+                'in': 'query',
+                'description': force_text(self.cursor_query_description),
+                'schema': {
+                    'type': 'integer',
+                },
+            }
+        ]
+        if self.page_size_query_param is not None:
+            parameters.append(
+                {
+                    'name': self.page_size_query_param,
+                    'required': False,
+                    'in': 'query',
+                    'description': force_text(self.page_size_query_description),
+                    'schema': {
+                        'type': 'integer',
+                    },
+                }
+            )
+        return parameters

rest_framework/schemas/generators.py

@@ -193,6 +193,10 @@ class EndpointEnumerator(object):
         """
         Given a URL conf regex, return a URI template string.
         """
+        # ???: Would it be feasible to adjust this such that we generate the
+        # path, plus the kwargs, plus the type from the convertor, such that we
+        # could feed that straight into the parameter schema object?
+
         path = simplify_regex(path_regex)
 
         # Strip Django 2.0 convertors as they are incompatible with uritemplate format
@@ -232,35 +236,18 @@ class EndpointEnumerator(object):
         return [method for method in methods if method not in ('OPTIONS', 'HEAD')]
 
 
-class SchemaGenerator(object):
-    # Map HTTP methods onto actions.
-    default_mapping = {
-        'get': 'retrieve',
-        'post': 'create',
-        'put': 'update',
-        'patch': 'partial_update',
-        'delete': 'destroy',
-    }
+class BaseSchemaGenerator(object):
     endpoint_inspector_cls = EndpointEnumerator
 
-    # Map the method names we use for viewset actions onto external schema names.
-    # These give us names that are more suitable for the external representation.
-    # Set by 'SCHEMA_COERCE_METHOD_NAMES'.
-    coerce_method_names = None
-
     # 'pk' isn't great as an externally exposed name for an identifier,
     # so by default we prefer to use the actual model field name for schemas.
     # Set by 'SCHEMA_COERCE_PATH_PK'.
     coerce_path_pk = None
 
     def __init__(self, title=None, url=None, description=None, patterns=None, urlconf=None):
-        assert coreapi, '`coreapi` must be installed for schema support.'
-        assert coreschema, '`coreschema` must be installed for schema support.'
-
         if url and not url.endswith('/'):
             url += '/'
 
-        self.coerce_method_names = api_settings.SCHEMA_COERCE_METHOD_NAMES
         self.coerce_path_pk = api_settings.SCHEMA_COERCE_PATH_PK
 
         self.patterns = patterns
@@ -270,36 +257,15 @@ class SchemaGenerator(object):
         self.url = url
         self.endpoints = None
 
-    def get_schema(self, request=None, public=False):
-        """
-        Generate a `coreapi.Document` representing the API schema.
-        """
+    def _initialise_endpoints(self):
         if self.endpoints is None:
             inspector = self.endpoint_inspector_cls(self.patterns, self.urlconf)
             self.endpoints = inspector.get_api_endpoints()
 
-        links = self.get_links(None if public else request)
-        if not links:
-            return None
-
-        url = self.url
-        if not url and request is not None:
-            url = request.build_absolute_uri()
-
-        distribute_links(links)
-        return coreapi.Document(
-            title=self.title, description=self.description,
-            url=url, content=links
-        )
-
-    def get_links(self, request=None):
+    def _get_paths_and_endpoints(self, request):
         """
-        Return a dictionary containing all the links that should be
-        included in the API schema.
+        Generate (path, method, view) given (path, method, callback) for paths.
         """
-        links = LinkNode()
-
-        # Generate (path, method, view) given (path, method, callback).
         paths = []
         view_endpoints = []
         for path, method, callback in self.endpoints:
@@ -308,22 +274,48 @@ class SchemaGenerator(object):
             paths.append(path)
             view_endpoints.append((path, method, view))
 
-        # Only generate the path prefix for paths that will be included
-        if not paths:
-            return None
-        prefix = self.determine_path_prefix(paths)
+        return paths, view_endpoints
 
-        for path, method, view in view_endpoints:
-            if not self.has_view_permissions(path, method, view):
-                continue
-            link = view.schema.get_link(path, method, base_url=self.url)
-            subpath = path[len(prefix):]
-            keys = self.get_keys(subpath, method, view)
-            insert_into(links, keys, link)
+    def create_view(self, callback, method, request=None):
+        """
+        Given a callback, return an actual view instance.
+        """
+        view = callback.cls(**getattr(callback, 'initkwargs', {}))
+        view.args = ()
+        view.kwargs = {}
+        view.format_kwarg = None
+        view.request = None
+        view.action_map = getattr(callback, 'actions', None)
 
-        return links
+        actions = getattr(callback, 'actions', None)
+        if actions is not None:
+            if method == 'OPTIONS':
+                view.action = 'metadata'
+            else:
+                view.action = actions.get(method.lower())
 
-    # Methods used when we generate a view instance from the raw callback...
+        if request is not None:
+            view.request = clone_request(request, method)
+
+        return view
+
+    def coerce_path(self, path, method, view):
+        """
+        Coerce {pk} path arguments into the name of the model field,
+        where possible. This is cleaner for an external representation.
+        (Ie. "this is an identifier", not "this is a database primary key")
+        """
+        if not self.coerce_path_pk or '{pk}' not in path:
+            return path
+        model = getattr(getattr(view, 'queryset', None), 'model', None)
+        if model:
+            field_name = get_pk_name(model)
+        else:
+            field_name = 'id'
+        return path.replace('{pk}', '{%s}' % field_name)
+
+    def get_schema(self, request=None, public=False):
+        raise NotImplementedError(".get_schema() must be implemented in subclasses.")
 
     def determine_path_prefix(self, paths):
         """
@@ -356,29 +348,6 @@ class SchemaGenerator(object):
             prefixes.append('/' + prefix + '/')
         return common_path(prefixes)
 
-    def create_view(self, callback, method, request=None):
-        """
-        Given a callback, return an actual view instance.
-        """
-        view = callback.cls(**getattr(callback, 'initkwargs', {}))
-        view.args = ()
-        view.kwargs = {}
-        view.format_kwarg = None
-        view.request = None
-        view.action_map = getattr(callback, 'actions', None)
-
-        actions = getattr(callback, 'actions', None)
-        if actions is not None:
-            if method == 'OPTIONS':
-                view.action = 'metadata'
-            else:
-                view.action = actions.get(method.lower())
-
-        if request is not None:
-            view.request = clone_request(request, method)
-
-        return view
-
     def has_view_permissions(self, path, method, view):
         """
         Return `True` if the incoming request has the correct view permissions.
@@ -392,23 +361,77 @@ class SchemaGenerator(object):
             return False
         return True
 
-    def coerce_path(self, path, method, view):
+
+class SchemaGenerator(BaseSchemaGenerator):
+    """
+    Original CoreAPI version.
+    """
+    # Map HTTP methods onto actions.
+    default_mapping = {
+        'get': 'retrieve',
+        'post': 'create',
+        'put': 'update',
+        'patch': 'partial_update',
+        'delete': 'destroy',
+    }
+
+    # Map the method names we use for viewset actions onto external schema names.
+    # These give us names that are more suitable for the external representation.
+    # Set by 'SCHEMA_COERCE_METHOD_NAMES'.
+    coerce_method_names = None
+
+    def __init__(self, title=None, url=None, description=None, patterns=None, urlconf=None):
+        assert coreapi, '`coreapi` must be installed for schema support.'
+        assert coreschema, '`coreschema` must be installed for schema support.'
+
+        super(SchemaGenerator, self).__init__(title, url, description, patterns, urlconf)
+        self.coerce_method_names = api_settings.SCHEMA_COERCE_METHOD_NAMES
+
+    def get_links(self, request=None):
         """
-        Coerce {pk} path arguments into the name of the model field,
-        where possible. This is cleaner for an external representation.
-        (Ie. "this is an identifier", not "this is a database primary key")
+        Return a dictionary containing all the links that should be
+        included in the API schema.
         """
-        if not self.coerce_path_pk or '{pk}' not in path:
-            return path
-        model = getattr(getattr(view, 'queryset', None), 'model', None)
-        if model:
-            field_name = get_pk_name(model)
-        else:
-            field_name = 'id'
-        return path.replace('{pk}', '{%s}' % field_name)
+        links = LinkNode()
+
+        paths, view_endpoints = self._get_paths_and_endpoints(request)
+
+        # Only generate the path prefix for paths that will be included
+        if not paths:
+            return None
+        prefix = self.determine_path_prefix(paths)
+
+        for path, method, view in view_endpoints:
+            if not self.has_view_permissions(path, method, view):
+                continue
+            link = view.schema.get_link(path, method, base_url=self.url)
+            subpath = path[len(prefix):]
+            keys = self.get_keys(subpath, method, view)
+            insert_into(links, keys, link)
+
+        return links
+
+    def get_schema(self, request=None, public=False):
+        """
+        Generate a `coreapi.Document` representing the API schema.
+        """
+        self._initialise_endpoints()
+
+        links = self.get_links(None if public else request)
+        if not links:
+            return None
+
+        url = self.url
+        if not url and request is not None:
+            url = request.build_absolute_uri()
+
+        distribute_links(links)
+        return coreapi.Document(
+            title=self.title, description=self.description,
+            url=url, content=links
+        )
 
     # Method for generating the link layout....
-
     def get_keys(self, subpath, method, view):
         """
         Return a list of keys that should be used to layout a link within
@@ -452,3 +475,55 @@ class SchemaGenerator(object):
 
         # Default action, eg "/users/", "/users/{pk}/"
         return named_path_components + [action]
+
+
+class OpenAPISchemaGenerator(BaseSchemaGenerator):
+
+    def get_info(self):
+        info = {
+            'title': self.title,
+            'version': 'TODO',
+        }
+
+        if self.description is not None:
+            info['description'] = self.description
+
+        return info
+
+    def get_paths(self, request=None):
+        result = {}
+
+        paths, view_endpoints = self._get_paths_and_endpoints(request)
+
+        # Only generate the path prefix for paths that will be included
+        if not paths:
+            return None
+        prefix = self.determine_path_prefix(paths)
+
+        for path, method, view in view_endpoints:
+            if not self.has_view_permissions(path, method, view):
+                continue
+            operation = view.schema.get_operation(path, method)
+            subpath = '/' + path[len(prefix):]
+            result.setdefault(subpath, {})
+            result[subpath][method.lower()] = operation
+
+        return result
+
+    def get_schema(self, request=None, public=False):
+        """
+        Generate a OpenAPI schema.
+        """
+        self._initialise_endpoints()
+
+        paths = self.get_paths(None if public else request)
+        if not paths:
+            return None
+
+        schema = {
+            'openapi': '3.0.2',
+            'info': self.get_info(),
+            'paths': paths,
+        }
+
+        return schema

rest_framework/schemas/inspectors.py

@@ -179,20 +179,6 @@ class ViewInspector(object):
     def view(self):
         self._view = None
 
-    def get_link(self, path, method, base_url):
-        """
-        Generate `coreapi.Link` for self.view, path and method.
-
-        This is the main _public_ access point.
-
-        Parameters:
-
-        * path: Route path for view from URLConf.
-        * method: The HTTP request method.
-        * base_url: The project "mount point" as given to SchemaGenerator
-        """
-        raise NotImplementedError(".get_link() must be overridden.")
-
 
 class AutoSchema(ViewInspector):
     """
@@ -213,6 +199,17 @@ class AutoSchema(ViewInspector):
         self._manual_fields = manual_fields
 
     def get_link(self, path, method, base_url):
+        """
+        Generate `coreapi.Link` for self.view, path and method.
+
+        This is the main _public_ access point.
+
+        Parameters:
+
+        * path: Route path for view from URLConf.
+        * method: The HTTP request method.
+        * base_url: The project "mount point" as given to SchemaGenerator
+        """
         fields = self.get_path_fields(path, method)
         fields += self.get_serializer_fields(path, method)
         fields += self.get_pagination_fields(path, method)
@@ -509,3 +506,246 @@ class DefaultSchema(ViewInspector):
         inspector = inspector_class()
         inspector.view = instance
         return inspector
+
+
+class OpenAPIAutoSchema(ViewInspector):
+
+    content_types = ['application/json']
+
+    def get_operation(self, path, method):
+        operation = {}
+
+        parameters = []
+        parameters += self._get_path_parameters(path, method)
+        parameters += self._get_pagination_parameters(path, method)
+        parameters += self._get_filter_parameters(path, method)
+        operation['parameters'] = parameters
+
+        request_body = self._get_request_body(path, method)
+        if request_body:
+            operation['requestBody'] = request_body
+        operation['responses'] = self._get_responses(path, method)
+
+        return operation
+
+    def _get_path_parameters(self, path, method):
+        """
+        Return a list of parameters from templated path variables.
+        """
+        model = getattr(getattr(self.view, 'queryset', None), 'model', None)
+        parameters = []
+
+        for variable in uritemplate.variables(path):
+            description = ''
+            if model is not None:  # TODO: test this.
+                # Attempt to infer a field description if possible.
+                try:
+                    model_field = model._meta.get_field(variable)
+                except Exception:
+                    model_field = None
+
+                if model_field is not None and model_field.help_text:
+                    description = force_text(model_field.help_text)
+                elif model_field is not None and model_field.primary_key:
+                    description = get_pk_description(model, model_field)
+
+            parameter = {
+                "name": variable,
+                "in": "path",
+                "required": True,
+                "description": description,
+                'schema': {
+                    'type': 'string',  # TODO: integer, pattern, ...
+                },
+            }
+            parameters.append(parameter)
+
+        return parameters
+
+    def _get_filter_parameters(self, path, method):
+        if not self._allows_filters(path, method):
+            return []
+        parameters = []
+        for filter_backend in self.view.filter_backends:
+            parameters += filter_backend().get_schema_operation_parameters(self.view)
+        return parameters
+
+    def _allows_filters(self, path, method):
+        """
+        Determine whether to include filter Fields in schema.
+
+        Default implementation looks for ModelViewSet or GenericAPIView
+        actions/methods that cause filtering on the default implementation.
+        """
+        if getattr(self.view, 'filter_backends', None) is None:
+            return False
+        if hasattr(self.view, 'action'):
+            return self.view.action in ["list", "retrieve", "update", "partial_update", "destroy"]
+        return method.lower() in ["get", "put", "patch", "delete"]
+
+    def _get_pagination_parameters(self, path, method):
+        view = self.view
+
+        if not is_list_view(path, method, view):
+            return []
+
+        pagination = getattr(view, 'pagination_class', None)
+        if not pagination:
+            return []
+
+        paginator = view.pagination_class()
+        return paginator.get_schema_operation_parameters(view)
+
+    def _map_field(self, field):
+
+        # Nested Serializers, `many` or not.
+        if isinstance(field, serializers.ListSerializer):
+            return {
+                'type': 'array',
+                'items': self._map_serializer(field.child)
+            }
+        if isinstance(field, serializers.Serializer):
+            return {
+                'type': 'object',
+                'properties': self._map_serializer(field)
+            }
+
+        # Related fields.
+        if isinstance(field, serializers.ManyRelatedField):
+            return {
+                'type': 'array',
+                'items': self._map_field(field.child_relation)
+            }
+        if isinstance(field, serializers.PrimaryKeyRelatedField):
+            model = getattr(field.queryset, 'model', None)
+            if model is not None:
+                model_field = model._meta.pk
+                if isinstance(model_field, models.AutoField):
+                    return {'type': 'integer'}
+
+        # ChoiceFields (single and multiple).
+        # Q:
+        # - Is 'type' required?
+        # - can we determine the TYPE of a choicefield?
+        if isinstance(field, serializers.MultipleChoiceField):
+            return {
+                'type': 'array',
+                'items': {
+                    'enum': list(field.choices)
+                },
+            }
+
+        if isinstance(field, serializers.ChoiceField):
+            return {
+                'enum': list(field.choices),
+            }
+
+        # ListField.
+        if isinstance(field, serializers.ListField):
+            return {
+                'type': 'array',
+            }
+
+        # Simplest cases, default to 'string' type:
+        FIELD_CLASS_SCHEMA_TYPE = {
+            serializers.BooleanField: 'boolean',
+            serializers.DecimalField: 'number',
+            serializers.FloatField: 'number',
+            serializers.IntegerField: 'integer',
+            serializers.DateField: 'date',
+            serializers.DateTimeField: 'date-time',
+            serializers.JSONField: 'object',
+            serializers.DictField: 'object',
+        }
+        return {'type': FIELD_CLASS_SCHEMA_TYPE.get(field.__class__, 'string')}
+
+    def _map_serializer(self, serializer):
+        # Assuming we have a valid serializer instance.
+        # TODO:
+        #   - field is Nested or List serializer.
+        #   - Handle read_only/write_only for request/response differences.
+        #       - could do this with readOnly/writeOnly and then filter dict.
+        required = []
+        properties = {}
+
+        for field in serializer.fields.values():
+            if isinstance(field, serializers.HiddenField):
+                continue
+
+            if field.required:
+                required.append(field.field_name)
+
+            schema = self._map_field(field)
+            if field.read_only:
+                schema['readOnly'] = True
+            if field.write_only:
+                schema['writeOnly'] = True
+            if field.allow_null:
+                schema['nullable'] = True
+
+            properties[field.field_name] = schema
+        return {
+            'required': required,
+            'properties': properties,
+        }
+
+    def _get_request_body(self, path, method):
+        view = self.view
+
+        if method not in ('PUT', 'PATCH', 'POST'):
+            return {}
+
+        if not hasattr(view, 'get_serializer'):
+            return {}
+
+        try:
+            serializer = view.get_serializer()
+        except exceptions.APIException:
+            serializer = None
+            warnings.warn('{}.get_serializer() raised an exception during '
+                          'schema generation. Serializer fields will not be '
+                          'generated for {} {}.'
+                          .format(view.__class__.__name__, method, path))
+
+        if not isinstance(serializer, serializers.Serializer):
+            return {}
+
+        content = self._map_serializer(serializer)
+        # No required fields for PATCH
+        if method == 'PATCH':
+            del content['required']
+        # No read_only fields for request.
+        for name, schema in content['properties'].items():
+            if 'readOnly' in schema:
+                del content['properties']['name']
+
+        return {
+            'content': {ct: content for ct in self.content_types}
+        }
+
+    def _get_responses(self, path, method):
+        # TODO: Handle multiple codes.
+        content = {}
+        view = self.view
+        if hasattr(view, 'get_serializer'):
+            try:
+                serializer = view.get_serializer()
+            except exceptions.APIException:
+                serializer = None
+                warnings.warn('{}.get_serializer() raised an exception during '
+                              'schema generation. Serializer fields will not be '
+                              'generated for {} {}.'
+                              .format(view.__class__.__name__, method, path))
+
+            if isinstance(serializer, serializers.Serializer):
+                content = self._map_serializer(serializer)
+                # No write_only fields for response.
+                for name, schema in content['properties'].items():
+                    if 'writeOnly' in schema:
+                        del content['properties']['name']
+
+        return {
+            '200': {
+                'content': {ct: content for ct in self.content_types}
+            }
+        }

rest_framework/settings.py

@@ -56,7 +56,7 @@ DEFAULTS = {
     'DEFAULT_FILTER_BACKENDS': (),
 
     # Schema
-    'DEFAULT_SCHEMA_CLASS': 'rest_framework.schemas.AutoSchema',
+    'DEFAULT_SCHEMA_CLASS': 'rest_framework.schemas.inspectors.OpenAPIAutoSchema',
 
     # Throttling
     'DEFAULT_THROTTLE_RATES': {

tests/schemas/test_coreapi.py

@@ -24,7 +24,8 @@ from rest_framework.utils import formatting
 from rest_framework.views import APIView
 from rest_framework.viewsets import GenericViewSet, ModelViewSet
 
-from .models import BasicModel, ForeignKeySource, ManyToManySource
+from . import views
+from ..models import BasicModel, ForeignKeySource, ManyToManySource
 
 factory = APIRequestFactory()
 
@@ -148,7 +149,7 @@ urlpatterns = [
 
 
 @unittest.skipUnless(coreapi, 'coreapi is not installed')
-@override_settings(ROOT_URLCONF='tests.test_schemas')
+@override_settings(ROOT_URLCONF=__name__, REST_FRAMEWORK={'DEFAULT_SCHEMA_CLASS': 'rest_framework.schemas.AutoSchema'})
 class TestRouterGeneratedSchema(TestCase):
     def test_anonymous_request(self):
         client = APIClient()
@@ -382,30 +383,14 @@ class MethodLimitedViewSet(ExampleViewSet):
     http_method_names = ['get', 'head', 'options']
 
 
-class ExampleListView(APIView):
-    permission_classes = [permissions.IsAuthenticatedOrReadOnly]
-
-    def get(self, *args, **kwargs):
-        pass
-
-    def post(self, request, *args, **kwargs):
-        pass
-
-
-class ExampleDetailView(APIView):
-    permission_classes = [permissions.IsAuthenticatedOrReadOnly]
-
-    def get(self, *args, **kwargs):
-        pass
-
-
 @unittest.skipUnless(coreapi, 'coreapi is not installed')
+@override_settings(REST_FRAMEWORK={'DEFAULT_SCHEMA_CLASS': 'rest_framework.schemas.AutoSchema'})
 class TestSchemaGenerator(TestCase):
     def setUp(self):
         self.patterns = [
-            url(r'^example/?$', ExampleListView.as_view()),
-            url(r'^example/(?P<pk>\d+)/?$', ExampleDetailView.as_view()),
-            url(r'^example/(?P<pk>\d+)/sub/?$', ExampleDetailView.as_view()),
+            url(r'^example/?$', views.ExampleListView.as_view()),
+            url(r'^example/(?P<pk>\d+)/?$', views.ExampleDetailView.as_view()),
+            url(r'^example/(?P<pk>\d+)/sub/?$', views.ExampleDetailView.as_view()),
         ]
 
     def test_schema_for_regular_views(self):
@@ -453,12 +438,13 @@ class TestSchemaGenerator(TestCase):
 
 @unittest.skipUnless(coreapi, 'coreapi is not installed')
 @unittest.skipUnless(path, 'needs Django 2')
+@override_settings(REST_FRAMEWORK={'DEFAULT_SCHEMA_CLASS': 'rest_framework.schemas.AutoSchema'})
 class TestSchemaGeneratorDjango2(TestCase):
     def setUp(self):
         self.patterns = [
-            path('example/', ExampleListView.as_view()),
-            path('example/<int:pk>/', ExampleDetailView.as_view()),
-            path('example/<int:pk>/sub/', ExampleDetailView.as_view()),
+            path('example/', views.ExampleListView.as_view()),
+            path('example/<int:pk>/', views.ExampleDetailView.as_view()),
+            path('example/<int:pk>/sub/', views.ExampleDetailView.as_view()),
         ]
 
     def test_schema_for_regular_views(self):
@@ -505,12 +491,13 @@ class TestSchemaGeneratorDjango2(TestCase):
 
 
 @unittest.skipUnless(coreapi, 'coreapi is not installed')
+@override_settings(REST_FRAMEWORK={'DEFAULT_SCHEMA_CLASS': 'rest_framework.schemas.AutoSchema'})
 class TestSchemaGeneratorNotAtRoot(TestCase):
     def setUp(self):
         self.patterns = [
-            url(r'^api/v1/example/?$', ExampleListView.as_view()),
-            url(r'^api/v1/example/(?P<pk>\d+)/?$', ExampleDetailView.as_view()),
-            url(r'^api/v1/example/(?P<pk>\d+)/sub/?$', ExampleDetailView.as_view()),
+            url(r'^api/v1/example/?$', views.ExampleListView.as_view()),
+            url(r'^api/v1/example/(?P<pk>\d+)/?$', views.ExampleDetailView.as_view()),
+            url(r'^api/v1/example/(?P<pk>\d+)/sub/?$', views.ExampleDetailView.as_view()),
         ]
 
     def test_schema_for_regular_views(self):
@@ -558,6 +545,7 @@ class TestSchemaGeneratorNotAtRoot(TestCase):
 
 
 @unittest.skipUnless(coreapi, 'coreapi is not installed')
+@override_settings(REST_FRAMEWORK={'DEFAULT_SCHEMA_CLASS': 'rest_framework.schemas.AutoSchema'})
 class TestSchemaGeneratorWithMethodLimitedViewSets(TestCase):
     def setUp(self):
         router = DefaultRouter()
@@ -622,13 +610,14 @@ class TestSchemaGeneratorWithMethodLimitedViewSets(TestCase):
 
 
 @unittest.skipUnless(coreapi, 'coreapi is not installed')
+@override_settings(REST_FRAMEWORK={'DEFAULT_SCHEMA_CLASS': 'rest_framework.schemas.AutoSchema'})
 class TestSchemaGeneratorWithRestrictedViewSets(TestCase):
     def setUp(self):
         router = DefaultRouter()
         router.register('example1', Http404ExampleViewSet, basename='example1')
         router.register('example2', PermissionDeniedExampleViewSet, basename='example2')
         self.patterns = [
-            url('^example/?$', ExampleListView.as_view()),
+            url('^example/?$', views.ExampleListView.as_view()),
             url(r'^', include(router.urls))
         ]
 
@@ -668,6 +657,7 @@ class ForeignKeySourceView(generics.CreateAPIView):
 
 
 @unittest.skipUnless(coreapi, 'coreapi is not installed')
+@override_settings(REST_FRAMEWORK={'DEFAULT_SCHEMA_CLASS': 'rest_framework.schemas.AutoSchema'})
 class TestSchemaGeneratorWithForeignKey(TestCase):
     def setUp(self):
         self.patterns = [
@@ -713,6 +703,7 @@ class ManyToManySourceView(generics.CreateAPIView):
 
 
 @unittest.skipUnless(coreapi, 'coreapi is not installed')
+@override_settings(REST_FRAMEWORK={'DEFAULT_SCHEMA_CLASS': 'rest_framework.schemas.AutoSchema'})
 class TestSchemaGeneratorWithManyToMany(TestCase):
     def setUp(self):
         self.patterns = [
@@ -747,6 +738,7 @@ class TestSchemaGeneratorWithManyToMany(TestCase):
 
 
 @unittest.skipUnless(coreapi, 'coreapi is not installed')
+@override_settings(REST_FRAMEWORK={'DEFAULT_SCHEMA_CLASS': 'rest_framework.schemas.AutoSchema'})
 class Test4605Regression(TestCase):
     def test_4605_regression(self):
         generator = SchemaGenerator()
@@ -762,6 +754,7 @@ class CustomViewInspector(AutoSchema):
     pass
 
 
+@override_settings(REST_FRAMEWORK={'DEFAULT_SCHEMA_CLASS': 'rest_framework.schemas.AutoSchema'})
 class TestAutoSchema(TestCase):
 
     def test_apiview_schema_descriptor(self):
@@ -777,7 +770,7 @@ class TestAutoSchema(TestCase):
         assert isinstance(view.schema, CustomViewInspector)
 
     def test_set_custom_inspector_class_via_settings(self):
-        with override_settings(REST_FRAMEWORK={'DEFAULT_SCHEMA_CLASS': 'tests.test_schemas.CustomViewInspector'}):
+        with override_settings(REST_FRAMEWORK={'DEFAULT_SCHEMA_CLASS': 'tests.schemas.test_coreapi.CustomViewInspector'}):
             view = APIView()
             assert isinstance(view.schema, CustomViewInspector)
 
@@ -971,6 +964,7 @@ class TestAutoSchema(TestCase):
             self.assertEqual(field_to_schema(case[0]), case[1])
 
 
+@override_settings(REST_FRAMEWORK={'DEFAULT_SCHEMA_CLASS': 'rest_framework.schemas.AutoSchema'})
 def test_docstring_is_not_stripped_by_get_description():
     class ExampleDocstringAPIView(APIView):
         """
@@ -1014,20 +1008,19 @@ class ExcludedAPIView(APIView):
         pass
 
 
-@api_view(['GET'])
-@schema(None)
-def excluded_fbv(request):
-    pass
-
-
-@api_view(['GET'])
-def included_fbv(request):
-    pass
-
-
 @unittest.skipUnless(coreapi, 'coreapi is not installed')
+@override_settings(REST_FRAMEWORK={'DEFAULT_SCHEMA_CLASS': 'rest_framework.schemas.AutoSchema'})
 class SchemaGenerationExclusionTests(TestCase):
     def setUp(self):
+        @api_view(['GET'])
+        @schema(None)
+        def excluded_fbv(request):
+            pass
+
+        @api_view(['GET'])
+        def included_fbv(request):
+            pass
+
         self.patterns = [
             url('^excluded-cbv/$', ExcludedAPIView.as_view()),
             url('^excluded-fbv/$', excluded_fbv),
@@ -1078,11 +1071,6 @@ class SchemaGenerationExclusionTests(TestCase):
         assert should_include == expected
 
 
-@api_view(["GET"])
-def simple_fbv(request):
-    pass
-
-
 class BasicModelSerializer(serializers.ModelSerializer):
     class Meta:
         model = BasicModel
@@ -1118,11 +1106,16 @@ naming_collisions_router.register(r'collision', NamingCollisionViewSet, basename
 
 
 @pytest.mark.skipif(not coreapi, reason='coreapi is not installed')
+@override_settings(REST_FRAMEWORK={'DEFAULT_SCHEMA_CLASS': 'rest_framework.schemas.AutoSchema'})
 class TestURLNamingCollisions(TestCase):
     """
     Ref: https://github.com/encode/django-rest-framework/issues/4704
     """
     def test_manually_routing_nested_routes(self):
+        @api_view(["GET"])
+        def simple_fbv(request):
+            pass
+
         patterns = [
             url(r'^test', simple_fbv),
             url(r'^test/list/', simple_fbv),
@@ -1228,6 +1221,10 @@ class TestURLNamingCollisions(TestCase):
 
     def test_url_under_same_key_not_replaced_another(self):
 
+        @api_view(["GET"])
+        def simple_fbv(request):
+            pass
+
         patterns = [
             url(r'^test/list/', simple_fbv),
             url(r'^test/(?P<pk>\d+)/list/', simple_fbv),
@@ -1303,7 +1300,8 @@ def test_head_and_options_methods_are_excluded():
 
 
 @pytest.mark.skipif(not coreapi, reason='coreapi is not installed')
-class TestAutoSchemaAllowsFilters(object):
+@override_settings(REST_FRAMEWORK={'DEFAULT_SCHEMA_CLASS': 'rest_framework.schemas.AutoSchema'})
+class TestAutoSchemaAllowsFilters(TestCase):
     class MockAPIView(APIView):
         filter_backends = [filters.OrderingFilter]
 

tests/schemas/test_openapi.py

@@ -0,0 +1,118 @@
+from django.conf.urls import url
+from django.test import RequestFactory, TestCase, override_settings
+
+from rest_framework import filters, pagination
+from rest_framework.request import Request
+from rest_framework.schemas.generators import OpenAPISchemaGenerator
+from rest_framework.schemas.inspectors import OpenAPIAutoSchema
+
+from . import views
+
+
+def create_request(path):
+    factory = RequestFactory()
+    request = Request(factory.get(path))
+    return request
+
+
+def create_view(view_cls, method, request):
+    generator = OpenAPISchemaGenerator()
+    view = generator.create_view(view_cls.as_view(), method, request)
+    return view
+
+
+class TestBasics(TestCase):
+    def dummy_view(request):
+        pass
+
+    def test_filters(self):
+        classes = [filters.SearchFilter, filters.OrderingFilter]
+        for c in classes:
+            f = c()
+            assert f.get_schema_operation_parameters(self.dummy_view)
+
+    def test_pagination(self):
+        classes = [pagination.PageNumberPagination, pagination.LimitOffsetPagination, pagination.CursorPagination]
+        for c in classes:
+            f = c()
+            assert f.get_schema_operation_parameters(self.dummy_view)
+
+
+class TestOperationIntrospection(TestCase):
+
+    def test_path_without_parameters(self):
+        path = '/example/'
+        method = 'GET'
+
+        view = create_view(
+            views.ExampleListView,
+            method,
+            create_request(path)
+        )
+        inspector = OpenAPIAutoSchema()
+        inspector.view = view
+
+        operation = inspector.get_operation(path, method)
+        assert operation == {
+            'parameters': [],
+            'responses': {'200': {'content': {'application/json': {}}}},
+        }
+
+    def test_path_with_id_parameter(self):
+        path = '/example/{id}/'
+        method = 'GET'
+
+        view = create_view(
+            views.ExampleDetailView,
+            method,
+            create_request(path)
+        )
+        inspector = OpenAPIAutoSchema()
+        inspector.view = view
+
+        parameters = inspector._get_path_parameters(path, method)
+        assert parameters == [{
+            'description': '',
+            'in': 'path',
+            'name': 'id',
+            'required': True,
+            'schema': {
+                'type': 'string',
+            },
+        }]
+
+
+@override_settings(REST_FRAMEWORK={'DEFAULT_SCHEMA_CLASS': 'rest_framework.schemas.inspectors.OpenAPIAutoSchema'})
+class TestGenerator(TestCase):
+
+    def test_override_settings(self):
+        assert isinstance(views.ExampleListView.schema, OpenAPIAutoSchema)
+
+    def test_paths_construction(self):
+        """Construction of the `paths` key."""
+        patterns = [
+            url(r'^example/?$', views.ExampleListView.as_view()),
+        ]
+        generator = OpenAPISchemaGenerator(patterns=patterns)
+        generator._initialise_endpoints()
+
+        paths = generator.get_paths()
+
+        assert '/example/' in paths
+        example_operations = paths['/example/']
+        assert len(example_operations) == 2
+        assert 'get' in example_operations
+        assert 'post' in example_operations
+
+    def test_schema_construction(self):
+        """Construction of the top level dictionary."""
+        patterns = [
+            url(r'^example/?$', views.ExampleListView.as_view()),
+        ]
+        generator = OpenAPISchemaGenerator(patterns=patterns)
+
+        request = create_request('/')
+        schema = generator.get_schema(request=request)
+
+        assert 'openapi' in schema
+        assert 'paths' in schema

tests/schemas/views.py

@@ -0,0 +1,19 @@
+from rest_framework import permissions
+from rest_framework.views import APIView
+
+
+class ExampleListView(APIView):
+    permission_classes = [permissions.IsAuthenticatedOrReadOnly]
+
+    def get(self, *args, **kwargs):
+        pass
+
+    def post(self, request, *args, **kwargs):
+        pass
+
+
+class ExampleDetailView(APIView):
+    permission_classes = [permissions.IsAuthenticatedOrReadOnly]
+
+    def get(self, *args, **kwargs):
+        pass

tests/test_generateschema.py

@@ -7,8 +7,8 @@ from django.test import TestCase
 from django.test.utils import override_settings
 from django.utils import six
 
-from rest_framework.compat import coreapi
-from rest_framework.utils import formatting, json
+from rest_framework.compat import coreapi, yaml
+from rest_framework.utils import json
 from rest_framework.views import APIView
 
 
@@ -31,58 +31,21 @@ class GenerateSchemaTests(TestCase):
         self.out = six.StringIO()
 
     @pytest.mark.skipif(six.PY2, reason='PyYAML unicode output is malformed on PY2.')
+    @pytest.mark.skipif(yaml is None, reason='PyYAML is required.')
     def test_renders_default_schema_with_custom_title_url_and_description(self):
-        expected_out = """info:
-                            description: Sample description
-                            title: SampleAPI
-                            version: ''
-                          openapi: 3.0.0
-                          paths:
-                            /:
-                              get:
-                                operationId: list
-                          servers:
-                          - url: http://api.sample.com/
-                          """
         call_command('generateschema',
                      '--title=SampleAPI',
                      '--url=http://api.sample.com',
                      '--description=Sample description',
                      stdout=self.out)
-
-        self.assertIn(formatting.dedent(expected_out), self.out.getvalue())
+        # Check valid YAML was output.
+        schema = yaml.load(self.out.getvalue())
+        assert schema['openapi'] == '3.0.2'
 
     def test_renders_openapi_json_schema(self):
-        expected_out = {
-            "openapi": "3.0.0",
-            "info": {
-                "version": "",
-                "title": "",
-                "description": ""
-            },
-            "servers": [
-                {
-                    "url": ""
-                }
-            ],
-            "paths": {
-                "/": {
-                    "get": {
-                        "operationId": "list"
-                    }
-                }
-            }
-        }
         call_command('generateschema',
                      '--format=openapi-json',
                      stdout=self.out)
+        # Check valid JSON was output.
         out_json = json.loads(self.out.getvalue())
-
-        self.assertDictEqual(out_json, expected_out)
-
-    def test_renders_corejson_schema(self):
-        expected_out = """{"_type":"document","":{"list":{"_type":"link","url":"/","action":"get"}}}"""
-        call_command('generateschema',
-                     '--format=corejson',
-                     stdout=self.out)
-        self.assertIn(expected_out, self.out.getvalue())
+        assert out_json['openapi'] == '3.0.2'