custom metadata for GET options

apps/api/metadata.py

@@ -0,0 +1,33 @@
+from rest_framework import serializers
+from rest_framework.metadata import SimpleMetadata
+from rest_framework.request import clone_request
+
+
+class ExpandedMetadata(SimpleMetadata):
+
+    def determine_actions(self, request, view):
+        """
+        For generic class based views we return information about
+        the fields that are accepted for 'PUT' and 'POST' methods.
+        """
+        actions = {}
+        for method in {'PUT', 'POST', "GET"} & set(view.allowed_methods):
+            view.request = clone_request(request, method)
+            try:
+                # Test global permissions
+                if hasattr(view, 'check_permissions'):
+                    view.check_permissions(view.request)
+                # Test object permissions
+                if method == 'PUT' and hasattr(view, 'get_object'):
+                    view.get_object()
+            except (exceptions.APIException, PermissionDenied, Http404):
+                pass
+            else:
+                # If user has appropriate permissions for the view, include
+                # appropriate metadata about the fields that should be supplied.
+                serializer = view.get_serializer()
+                actions[method] = self.get_serializer_info(serializer)
+            finally:
+                view.request = request
+
+        return actions