allow swagger and redoc settings to be overridden

When using site middleware there is no way to configure swagger
instances to have different login URLs or authentication mechanisms.
This change updates any global references to app settings to prefer a
local setting if it exists, and for backward compatibility it refers to
the global setting by default.

The following calls will need to be adjusted to account for the new
swagger_settings parameter that is passed:

- ``drf_yasg.utils.get_produces(...)``
- ViewInspector class (and user defined subclasses)
- Generator class (and user defined subclasses)

src/drf_yasg/generators.py

@@ -14,7 +14,7 @@
 from rest_framework.settings import api_settings
 
 from . import openapi
-from .app_settings import swagger_settings
+from .app_settings import swagger_settings as _swagger_settings
 from .errors import SwaggerGenerationError
 from .inspectors.field import get_basic_type_info, get_queryset_field, get_queryset_from_view
 from .openapi import ReferenceResolver, SwaggerDict
@@ -171,7 +171,7 @@ class OpenAPISchemaGenerator(object):
     endpoint_enumerator_class = EndpointEnumerator
     reference_resolver_class = ReferenceResolver
 
-    def __init__(self, info, version='', url=None, patterns=None, urlconf=None):
+    def __init__(self, info, version='', url=None, patterns=None, urlconf=None, swagger_settings=_swagger_settings):
         """
 
         :param openapi.Info info: information about the API
@@ -187,9 +187,11 @@ def __init__(self, info, version='', url=None, patterns=None, urlconf=None):
         :param patterns: if given, only these patterns will be enumerated for inclusion in the API spec
         :param urlconf: if patterns is not given, use this urlconf to enumerate patterns;
             if not given, the default urlconf is used
+        :param swagger_settings: if given global swagger_settings are overridden with local settings
         """
         self._gen = SchemaGenerator(info.title, url, info.get('description', ''), patterns, urlconf)
         self.info = info
+        self.swagger_settings = swagger_settings
         self.version = version
         self.consumes = []
         self.produces = []
@@ -215,7 +217,7 @@ def get_security_definitions(self):
         :return: the security schemes usable with this API
         :rtype: dict[str,dict] or None
         """
-        security_definitions = swagger_settings.SECURITY_DEFINITIONS
+        security_definitions = self.swagger_settings.SECURITY_DEFINITIONS
         if security_definitions is not None:
             security_definitions = SwaggerDict._as_odict(security_definitions, {})
 
@@ -229,7 +231,7 @@ def get_security_requirements(self, security_definitions):
         :return: the security schemes accepted by default
         :rtype: list[dict[str,list[str]]] or None
         """
-        security_requirements = swagger_settings.SECURITY_REQUIREMENTS
+        security_requirements = self.swagger_settings.SECURITY_REQUIREMENTS
         if security_requirements is None:
             security_requirements = [{security_scheme: []} for security_scheme in security_definitions]
 
@@ -250,7 +252,7 @@ def get_schema(self, request=None, public=False):
         endpoints = self.get_endpoints(request)
         components = self.reference_resolver_class(openapi.SCHEMA_DEFINITIONS, force_init=True)
         self.consumes = get_consumes(api_settings.DEFAULT_PARSER_CLASSES)
-        self.produces = get_produces(api_settings.DEFAULT_RENDERER_CLASSES)
+        self.produces = get_produces(api_settings.DEFAULT_RENDERER_CLASSES, self.swagger_settings)
         paths, prefix = self.get_paths(endpoints, components, request, public)
 
         security_definitions = self.get_security_definitions()
@@ -441,7 +443,7 @@ def get_operation(self, view, path, prefix, method, components, request):
 
         # the inspector class can be specified, in decreasing order of priorty,
         #   1. globaly via DEFAULT_AUTO_SCHEMA_CLASS
-        view_inspector_cls = swagger_settings.DEFAULT_AUTO_SCHEMA_CLASS
+        view_inspector_cls = self.swagger_settings.DEFAULT_AUTO_SCHEMA_CLASS
         #   2. on the view/viewset class
         view_inspector_cls = getattr(view, 'swagger_schema', view_inspector_cls)
         #   3. on the swagger_auto_schema decorator
@@ -450,7 +452,8 @@ def get_operation(self, view, path, prefix, method, components, request):
         if view_inspector_cls is None:
             return None
 
-        view_inspector = view_inspector_cls(view, path, method, components, request, overrides, operation_keys)
+        view_inspector = view_inspector_cls(
+            view, path, method, components, request, overrides, operation_keys, self.swagger_settings)
         operation = view_inspector.get_operation(operation_keys)
         if operation is None:
             return None

src/drf_yasg/inspectors/__init__.py

@@ -1,4 +1,3 @@
-from ..app_settings import swagger_settings
 from .base import (
     BaseInspector, FieldInspector, FilterInspector, NotHandled, PaginatorInspector, SerializerInspector, ViewInspector
 )
@@ -10,11 +9,6 @@
 from .query import CoreAPICompatInspector, DjangoRestResponsePagination
 from .view import SwaggerAutoSchema
 
-# these settings must be accessed only after defining/importing all the classes in this module to avoid ImportErrors
-ViewInspector.field_inspectors = swagger_settings.DEFAULT_FIELD_INSPECTORS
-ViewInspector.filter_inspectors = swagger_settings.DEFAULT_FILTER_INSPECTORS
-ViewInspector.paginator_inspectors = swagger_settings.DEFAULT_PAGINATOR_INSPECTORS
-
 __all__ = [
     # base inspectors
     'BaseInspector', 'FilterInspector', 'PaginatorInspector', 'FieldInspector', 'SerializerInspector', 'ViewInspector',

src/drf_yasg/inspectors/base.py

@@ -4,6 +4,7 @@
 from rest_framework import serializers
 
 from .. import openapi
+from ..app_settings import swagger_settings as _swagger_settings
 from ..utils import force_real_str, get_field_default, get_object_classes, is_list_view
 
 #: Sentinel value that inspectors must return to signal that they do not know how to handle an object
@@ -60,19 +61,21 @@ def call_view_method(view, method_name, fallback_attr=None, default=None):
 
 
 class BaseInspector(object):
-    def __init__(self, view, path, method, components, request):
+    def __init__(self, view, path, method, components, request, swagger_settings=_swagger_settings):
         """
         :param rest_framework.views.APIView view: the view associated with this endpoint
         :param str path: the path component of the operation URL
         :param str method: the http method of the operation
         :param openapi.ReferenceResolver components: referenceable components
         :param rest_framework.request.Request request: the request made against the schema view; can be None
+        :param swagger_settings: if given global swagger_settings are overridden with local settings
         """
         self.view = view
         self.path = path
         self.method = method
         self.components = components
         self.request = request
+        self.swagger_settings = swagger_settings
 
     def process_result(self, result, method_name, obj, **kwargs):
         """After an inspector handles an object (i.e. returns a value other than :data:`.NotHandled`), all inspectors
@@ -193,8 +196,8 @@ def get_filter_parameters(self, filter_backend):
 class FieldInspector(BaseInspector):
     """Base inspector for serializers and serializer fields. """
 
-    def __init__(self, view, path, method, components, request, field_inspectors):
-        super(FieldInspector, self).__init__(view, path, method, components, request)
+    def __init__(self, view, path, method, components, request, field_inspectors, swagger_settings=_swagger_settings):
+        super(FieldInspector, self).__init__(view, path, method, components, request, swagger_settings)
         self.field_inspectors = field_inspectors
 
     def add_manual_fields(self, serializer_or_field, schema):
@@ -345,18 +348,42 @@ class ViewInspector(BaseInspector):
     #: methods which are assumed to return a list of objects when present on non-detail endpoints
     implicit_list_response_methods = ('GET',)
 
-    # real values set in __init__ to prevent import errors
-    field_inspectors = []  #:
-    filter_inspectors = []  #:
-    paginator_inspectors = []  #:
+    _field_inspectors = None
+    _filter_inspectors = None
+    _paginator_inspectors = None
 
-    def __init__(self, view, path, method, components, request, overrides):
+    @property
+    def field_inspectors(self):
+        return self._field_inspectors or self.swagger_settings.DEFAULT_FIELD_INSPECTORS
+
+    @field_inspectors.setter
+    def field_inspectors(self, value):
+        self._field_inspectors = value
+
+    @property
+    def filter_inspectors(self):
+        return self._filter_inspectors or self.swagger_settings.DEFAULT_FILTER_INSPECTORS
+
+    @filter_inspectors.setter
+    def filter_inspectors(self, value):
+        self._filter_inspectors = value
+
+    @property
+    def paginator_inspectors(self):
+        return self._paginator_inspectors or self.swagger_settings.DEFAULT_PAGINATOR_INSPECTORS
+
+    @paginator_inspectors.setter
+    def paginator_inspectors(self, value):
+        self._paginator_inspectors = value
+
+    def __init__(self, view, path, method, components, request, overrides, swagger_settings=_swagger_settings):
         """
         Inspector class responsible for providing :class:`.Operation` definitions given a view, path and method.
 
         :param dict overrides: manual overrides as passed to :func:`@swagger_auto_schema <.swagger_auto_schema>`
+        :param swagger_settings: if given global swagger_settings are overridden with local settings
         """
-        super(ViewInspector, self).__init__(view, path, method, components, request)
+        super(ViewInspector, self).__init__(view, path, method, components, request, swagger_settings)
         self.overrides = overrides
         self._prepend_inspector_overrides('field_inspectors')
         self._prepend_inspector_overrides('filter_inspectors')

src/drf_yasg/inspectors/view.py

@@ -6,6 +6,7 @@
 from rest_framework.status import is_success
 
 from .. import openapi
+from ..app_settings import swagger_settings as _swagger_settings
 from ..errors import SwaggerGenerationError
 from ..utils import (
     filter_none, force_real_str, force_serializer_instance, get_consumes, get_produces, guess_response_status,
@@ -17,8 +18,8 @@
 
 
 class SwaggerAutoSchema(ViewInspector):
-    def __init__(self, view, path, method, components, request, overrides, operation_keys=None):
-        super(SwaggerAutoSchema, self).__init__(view, path, method, components, request, overrides)
+    def __init__(self, view, path, method, components, request, overrides, operation_keys=None, swagger_settings=_swagger_settings):
+        super(SwaggerAutoSchema, self).__init__(view, path, method, components, request, overrides, swagger_settings)
         self._sch = AutoSchema()
         self._sch.view = view
         self.operation_keys = operation_keys

src/drf_yasg/renderers.py

@@ -7,7 +7,7 @@
 from rest_framework.renderers import BaseRenderer, JSONRenderer, TemplateHTMLRenderer
 from rest_framework.utils import encoders, json
 
-from .app_settings import redoc_settings, swagger_settings
+from .app_settings import redoc_settings as _redoc_settings, swagger_settings as _swagger_settings
 from .codecs import VALIDATORS, OpenAPICodecJson, OpenAPICodecYaml
 from .openapi import Swagger
 from .utils import filter_none
@@ -63,6 +63,7 @@ class _UIRenderer(BaseRenderer):
     media_type = 'text/html'
     charset = 'utf-8'
     template = ''
+    swagger_settings = _swagger_settings
 
     def render(self, swagger, accepted_media_type=None, renderer_context=None):
         if not isinstance(swagger, Swagger):  # pragma: no cover
@@ -78,7 +79,7 @@ def set_context(self, renderer_context, swagger=None):
         renderer_context['title'] = swagger.info.title or '' if swagger else ''
         renderer_context['version'] = swagger.info.version or '' if swagger else ''
         renderer_context['oauth2_config'] = json.dumps(self.get_oauth2_config(), cls=encoders.JSONEncoder)
-        renderer_context['USE_SESSION_AUTH'] = swagger_settings.USE_SESSION_AUTH
+        renderer_context['USE_SESSION_AUTH'] = self.swagger_settings.USE_SESSION_AUTH
         renderer_context.update(self.get_auth_urls())
 
     def resolve_url(self, to):
@@ -102,14 +103,14 @@ def resolve_url(self, to):
 
     def get_auth_urls(self):
         urls = {
-            'LOGIN_URL': self.resolve_url(swagger_settings.LOGIN_URL),
-            'LOGOUT_URL': self.resolve_url(swagger_settings.LOGOUT_URL),
+            'LOGIN_URL': self.resolve_url(self.swagger_settings.LOGIN_URL),
+            'LOGOUT_URL': self.resolve_url(self.swagger_settings.LOGOUT_URL),
         }
 
         return filter_none(urls)
 
     def get_oauth2_config(self):
-        data = swagger_settings.OAUTH2_CONFIG
+        data = self.swagger_settings.OAUTH2_CONFIG
         assert isinstance(data, dict), "OAUTH2_CONFIG must be a dict"
         return data
 
@@ -132,28 +133,28 @@ def set_context(self, renderer_context, swagger=None):
 
     def get_swagger_ui_settings(self):
         data = {
-            'url': self.resolve_url(swagger_settings.SPEC_URL),
-            'operationsSorter': swagger_settings.OPERATIONS_SORTER,
-            'tagsSorter': swagger_settings.TAGS_SORTER,
-            'docExpansion': swagger_settings.DOC_EXPANSION,
-            'deepLinking': swagger_settings.DEEP_LINKING,
-            'showExtensions': swagger_settings.SHOW_EXTENSIONS,
-            'defaultModelRendering': swagger_settings.DEFAULT_MODEL_RENDERING,
-            'defaultModelExpandDepth': swagger_settings.DEFAULT_MODEL_DEPTH,
-            'defaultModelsExpandDepth': swagger_settings.DEFAULT_MODEL_DEPTH,
-            'showCommonExtensions': swagger_settings.SHOW_COMMON_EXTENSIONS,
-            'oauth2RedirectUrl': swagger_settings.OAUTH2_REDIRECT_URL,
-            'supportedSubmitMethods': swagger_settings.SUPPORTED_SUBMIT_METHODS,
-            'displayOperationId': swagger_settings.DISPLAY_OPERATION_ID,
-            'persistAuth': swagger_settings.PERSIST_AUTH,
-            'refetchWithAuth': swagger_settings.REFETCH_SCHEMA_WITH_AUTH,
-            'refetchOnLogout': swagger_settings.REFETCH_SCHEMA_ON_LOGOUT,
-            'fetchSchemaWithQuery': swagger_settings.FETCH_SCHEMA_WITH_QUERY,
+            'url': self.resolve_url(self.swagger_settings.SPEC_URL),
+            'operationsSorter': self.swagger_settings.OPERATIONS_SORTER,
+            'tagsSorter': self.swagger_settings.TAGS_SORTER,
+            'docExpansion': self.swagger_settings.DOC_EXPANSION,
+            'deepLinking': self.swagger_settings.DEEP_LINKING,
+            'showExtensions': self.swagger_settings.SHOW_EXTENSIONS,
+            'defaultModelRendering': self.swagger_settings.DEFAULT_MODEL_RENDERING,
+            'defaultModelExpandDepth': self.swagger_settings.DEFAULT_MODEL_DEPTH,
+            'defaultModelsExpandDepth': self.swagger_settings.DEFAULT_MODEL_DEPTH,
+            'showCommonExtensions': self.swagger_settings.SHOW_COMMON_EXTENSIONS,
+            'oauth2RedirectUrl': self.swagger_settings.OAUTH2_REDIRECT_URL,
+            'supportedSubmitMethods': self.swagger_settings.SUPPORTED_SUBMIT_METHODS,
+            'displayOperationId': self.swagger_settings.DISPLAY_OPERATION_ID,
+            'persistAuth': self.swagger_settings.PERSIST_AUTH,
+            'refetchWithAuth': self.swagger_settings.REFETCH_SCHEMA_WITH_AUTH,
+            'refetchOnLogout': self.swagger_settings.REFETCH_SCHEMA_ON_LOGOUT,
+            'fetchSchemaWithQuery': self.swagger_settings.FETCH_SCHEMA_WITH_QUERY,
         }
 
         data = filter_none(data)
-        if swagger_settings.VALIDATOR_URL != '':
-            data['validatorUrl'] = self.resolve_url(swagger_settings.VALIDATOR_URL)
+        if self.swagger_settings.VALIDATOR_URL != '':
+            data['validatorUrl'] = self.resolve_url(self.swagger_settings.VALIDATOR_URL)
 
         return data
 
@@ -162,21 +163,22 @@ class ReDocRenderer(_UIRenderer):
     """Renders a ReDoc web interface for schema browisng."""
     template = 'drf-yasg/redoc.html'
     format = 'redoc'
+    redoc_settings = _redoc_settings
 
     def set_context(self, renderer_context, swagger=None):
         super(ReDocRenderer, self).set_context(renderer_context, swagger)
         renderer_context['redoc_settings'] = json.dumps(self.get_redoc_settings(), cls=encoders.JSONEncoder)
 
     def get_redoc_settings(self):
         data = {
-            'url': self.resolve_url(redoc_settings.SPEC_URL),
-            'lazyRendering': redoc_settings.LAZY_RENDERING,
-            'hideHostname': redoc_settings.HIDE_HOSTNAME,
-            'expandResponses': redoc_settings.EXPAND_RESPONSES,
-            'pathInMiddlePanel': redoc_settings.PATH_IN_MIDDLE,
-            'nativeScrollbars': redoc_settings.NATIVE_SCROLLBARS,
-            'requiredPropsFirst': redoc_settings.REQUIRED_PROPS_FIRST,
-            'fetchSchemaWithQuery': redoc_settings.FETCH_SCHEMA_WITH_QUERY,
+            'url': self.resolve_url(self.redoc_settings.SPEC_URL),
+            'lazyRendering': self.redoc_settings.LAZY_RENDERING,
+            'hideHostname': self.redoc_settings.HIDE_HOSTNAME,
+            'expandResponses': self.redoc_settings.EXPAND_RESPONSES,
+            'pathInMiddlePanel': self.redoc_settings.PATH_IN_MIDDLE,
+            'nativeScrollbars': self.redoc_settings.NATIVE_SCROLLBARS,
+            'requiredPropsFirst': self.redoc_settings.REQUIRED_PROPS_FIRST,
+            'fetchSchemaWithQuery': self.redoc_settings.FETCH_SCHEMA_WITH_QUERY,
         }
 
         return filter_none(data)

src/drf_yasg/utils.py

@@ -15,7 +15,7 @@
 from rest_framework.utils import encoders, json
 from rest_framework.views import APIView
 
-from .app_settings import swagger_settings
+from .app_settings import swagger_settings as _swagger_settings
 
 logger = logging.getLogger(__name__)
 
@@ -387,7 +387,7 @@ def get_consumes(parser_classes):
     return non_form_media_types
 
 
-def get_produces(renderer_classes):
+def get_produces(renderer_classes, swagger_settings=_swagger_settings):
     """Extract ``produces`` MIME types from a list of renderer classes.
 
     :param list renderer_classes: renderer classes