fi(api): improve auth/preferences schema generation

Applying recommendation from https://github.com/tfranzel/drf-spectacular/issues/874

api/config/schema.py

@@ -1,35 +1,97 @@
 import os
 
-from drf_spectacular.contrib.django_oauth_toolkit import OpenApiAuthenticationExtension
-from drf_spectacular.plumbing import build_bearer_security_scheme_object
+from drf_spectacular.contrib.django_oauth_toolkit import (
+    DjangoOAuthToolkitScheme,
+    OpenApiAuthenticationExtension,
+)
+from drf_spectacular.extensions import (
+    OpenApiSerializerExtension,
+    OpenApiSerializerFieldExtension,
+)
+from drf_spectacular.plumbing import (
+    OpenApiTypes,
+    build_basic_type,
+    build_bearer_security_scheme_object,
+)
 
 
-class CustomOAuthExt(OpenApiAuthenticationExtension):
+class CustomRelatedFieldScheme(OpenApiSerializerFieldExtension):
+    target_class = "funkwhale_api.common.serializers.RelatedField"
+    match_subclasses = True
+
+    def map_serializer_field(self, auto_schema, direction):
+        if direction == "request":
+            return build_basic_type(OpenApiTypes.UUID)
+        elif direction == "response" and self.target.serializer:
+            component = auto_schema.resolve_serializer(
+                self.target.serializer, direction
+            )
+            return component.ref
+        else:
+            # happens for
+            # UserViewSet: UserWriteSerializer: not sure how this works for: avatar
+            # AlbumViewSet: AlbumCreateSerializer: not sure how this works for: artist
+            return build_basic_type(OpenApiTypes.UUID)
+
+
+class PreferenceSerializerScheme(OpenApiSerializerExtension):
+    target_class = "dynamic_preferences.api.serializers.PreferenceSerializer"
+    match_subclasses = True
+
+    def map_serializer(self, auto_schema, direction):
+        from dynamic_preferences.api.serializers import PreferenceSerializer
+
+        class Fix(PreferenceSerializer):
+            def get_default(self, o) -> str:
+                pass
+
+            def get_verbose_name(self, o) -> str:
+                pass
+
+            def get_identifier(self, o) -> str:
+                pass
+
+            def get_help_text(self, o) -> str:
+                pass
+
+            def get_additional_data(self, o) -> dict:
+                pass
+
+            def get_field(self, o) -> dict:
+                pass
+
+        return auto_schema._map_serializer(Fix, direction, bypass_extensions=True)
+
+
+class CustomOAuthScheme(DjangoOAuthToolkitScheme):
     target_class = "funkwhale_api.common.authentication.OAuth2Authentication"
-    name = "oauth2"
 
-    def get_security_definition(self, auto_schema):
-        from drf_spectacular.settings import spectacular_settings
-        from oauth2_provider.scopes import get_scopes_backend
+    def get_security_requirement(self, auto_schema):
+        from funkwhale_api.users.oauth.permissions import (
+            METHOD_SCOPE_MAPPING,
+            ScopePermission,
+        )
 
-        flows = {}
-        for flow_type in spectacular_settings.OAUTH2_FLOWS:
-            flows[flow_type] = {}
-            if flow_type in ("implicit", "authorizationCode"):
-                flows[flow_type][
-                    "authorizationUrl"
-                ] = spectacular_settings.OAUTH2_AUTHORIZATION_URL
-            if flow_type in ("password", "clientCredentials", "authorizationCode"):
-                flows[flow_type]["tokenUrl"] = spectacular_settings.OAUTH2_TOKEN_URL
-            if spectacular_settings.OAUTH2_REFRESH_URL:
-                flows[flow_type]["refreshUrl"] = spectacular_settings.OAUTH2_REFRESH_URL
-            scope_backend = get_scopes_backend()
-            flows[flow_type]["scopes"] = scope_backend.get_all_scopes()
+        for permission in auto_schema.view.get_permissions():
+            if isinstance(permission, ScopePermission):
+                scope_config = getattr(auto_schema.view, "required_scope", "noopscope")
 
-        return {"type": "oauth2", "flows": flows}
+                if isinstance(scope_config, str):
+                    scope_config = {
+                        "read": f"read:{scope_config}",
+                        "write": f"write:{scope_config}",
+                    }
+                    action = METHOD_SCOPE_MAPPING[
+                        auto_schema.view.request.method.lower()
+                    ]
+                    required_scope = scope_config[action]
+                else:
+                    required_scope = scope_config[auto_schema.view.action]
+
+                return {self.name: [required_scope]}
 
 
-class CustomApplicationTokenExt(OpenApiAuthenticationExtension):
+class CustomApplicationTokenScheme(OpenApiAuthenticationExtension):
     target_class = "funkwhale_api.common.authentication.ApplicationTokenAuthentication"
     name = "ApplicationToken"