GraphQlView: Do not 'instantiate_middleware' if middleware is already a MiddlewareManager (#952)

Author: msimon

graphene_django/views.py

@@ -15,6 +15,7 @@
 from graphql.error import GraphQLError
 from graphql.execution import ExecutionResult
 from graphql.type.schema import GraphQLSchema
+from graphql.execution.middleware import MiddlewareManager
 
 from .settings import graphene_settings
 
@@ -86,7 +87,10 @@ def __init__(
 
         self.schema = self.schema or schema
         if middleware is not None:
-            self.middleware = list(instantiate_middleware(middleware))
+            if isinstance(middleware, MiddlewareManager):
+                self.middleware = middleware
+            else:
+                self.middleware = list(instantiate_middleware(middleware))
         self.executor = executor
         self.root_value = root_value
         self.pretty = self.pretty or pretty