add format query parameter #110

drf_spectacular/openapi.py

@@ -149,6 +149,18 @@ def _process_override_parameters(self):
                 warn(f'could not resolve parameter annotation {parameter}. skipping.')
         return result
 
+    def _get_format_parameters(self):
+        parameters = []
+        formats = self.map_renderers('format')
+        if api_settings.URL_FORMAT_OVERRIDE and len(formats) > 1:
+            parameters.append(build_parameter_type(
+                name=api_settings.URL_FORMAT_OVERRIDE,
+                schema=build_basic_type(OpenApiTypes.STR),
+                location=OpenApiParameter.QUERY,
+                enum=formats
+            ))
+        return parameters
+
     def _get_parameters(self):
         def dict_helper(parameters):
             return {(p['name'], p['in']): p for p in parameters}
@@ -162,6 +174,7 @@ def dict_helper(parameters):
             **dict_helper(self._resolve_path_parameters(path_variables)),
             **dict_helper(self._get_filter_parameters()),
             **dict_helper(self._get_pagination_parameters()),
+            **dict_helper(self._get_format_parameters()),
         }
         # override/add @extend_schema parameters
         for key, parameter in override_parameters.items():
@@ -272,7 +285,7 @@ def _resolve_path_parameters(self, variables):
             description = ''
 
             resolved_parameter = resolve_regex_path_parameter(
-                self.path_regex, variable, self.map_formats(),
+                self.path_regex, variable, self.map_renderers('format'),
             )
 
             if resolved_parameter:
@@ -738,23 +751,12 @@ def _get_paginator(self):
     def map_parsers(self):
         return list(map(attrgetter('media_type'), self.view.parser_classes))
 
-    def map_renderers(self):
-        media_types = []
-        for renderer in self.view.renderer_classes:
-            # BrowsableAPIRenderer not relevant to OpenAPI spec
-            if renderer == renderers.BrowsableAPIRenderer:
-                continue
-            media_types.append(renderer.media_type)
-        return media_types
-
-    def map_formats(self):
-        formats = set()
-        for renderer in self.view.renderer_classes:
-            # BrowsableAPIRenderer not relevant to OpenAPI spec
-            if renderer == renderers.BrowsableAPIRenderer:
-                continue
-            formats.add(renderer.format)
-        return list(formats)
+    def map_renderers(self, attribute):
+        assert attribute in ['media_type', 'format']
+        return list(dict.fromkeys([
+            getattr(r, attribute) for r in self.view.renderer_classes
+            if r != renderers.BrowsableAPIRenderer
+        ]))
 
     def _get_serializer(self):
         view = self.view
@@ -900,7 +902,7 @@ def _get_response_for_code(self, serializer):
 
         return {
             'content': {
-                mt: {'schema': schema} for mt in self.map_renderers()
+                mt: {'schema': schema} for mt in self.map_renderers('media_type')
             },
             # Description is required by spec, but descriptions for each response code don't really
             # fit into our model. Description is therefore put into the higher level slots.

drf_spectacular/plumbing.py

@@ -234,8 +234,8 @@ def build_parameter_type(
         schema['explode'] = explode
     if style is not None:
         schema['style'] = style
-    if enum is not None:
-        schema['schema']['enum'] = enum
+    if enum:
+        schema['schema']['enum'] = sorted(enum)
     return schema
 
 

tests/test_extend_schema.yml

@@ -20,8 +20,8 @@ paths:
         schema:
           type: boolean
           enum:
-          - true
           - false
+          - true
         description: creation will be in the sandbox
       tags:
       - custom_tag

tests/test_i18n.yml

@@ -13,6 +13,13 @@ paths:
         - YAML: application/vnd.oai.openapi
         - JSON: application/vnd.oai.openapi+json
       parameters:
+      - in: query
+        name: format
+        schema:
+          type: string
+          enum:
+          - json
+          - yaml
       - in: query
         name: lang
         schema: