Add removeRoleFromUser API function

backend/database/schema.py

@@ -107,6 +107,23 @@ class AddRoleToUser(graphene.Mutation):
         return AddRoleToUser(user=user,role=role)
 
 
+class RemoveRoleFromUser(graphene.Mutation):
+    class Arguments:
+        username = graphene.String(required=True)
+        role = graphene.String(required=True)
+
+    ok = graphene.Boolean()
+
+    def mutate(self, info, username, role):
+        ok = False
+        user = user_datastore.db.session().query(UserModel).filter_by(username=username).first()
+        if user is not None:
+            user_datastore.remove_role_from_user(user, role)
+            user_datastore.commit()
+            ok = True
+        return RemoveRoleFromUser(ok=ok)
+
+
 class AddApplicationToUser(graphene.Mutation):
     class Arguments:
         username = graphene.String(required=True)
@@ -161,6 +178,7 @@ class Mutation(graphene.ObjectType):
     create_role = CreateRole.Field()
     create_application = CreateApplication.Field()
     add_role_to_user = AddRoleToUser.Field()
+    remove_role_from_user = RemoveRoleFromUser.Field()
     add_application_to_user = AddApplicationToUser.Field()
     delete_user = DeleteUser.Field()
     edit_user = EditUser.Field()

backend/test/test_graphql.py

@@ -155,6 +155,44 @@ class GraphQlTests(LiveServerTestCase):
         users = role["users"]["edges"]
         self.assertEqual(username, users[0]["node"]["username"])
 
+    def test_remove_role_from_user(self):
+        role_name = "testusers"
+        role_description = "A role assigned to users during unittests"
+        username = "graphqluser2"
+        password = "randompassword"
+        email = "user2@example.com"
+        self._create_role(role_name, role_description)
+        self._create_user(username, password, email)
+        querystring = '''
+        mutation{{
+          addRoleToUser(
+            username: "{0}",
+            role: "{1}"){{
+              user{{username}},
+              role{{name}}
+            }}}}'''.format(username, role_name)
+        self.client.execute(querystring)
+        querystring = '''
+        mutation{{
+          removeRoleFromUser(
+            username: "{0}",
+            role: "{1}"){{ ok }}
+            }}'''.format(username, role_name)
+        result = loads(self.client.execute(querystring))
+        self.assertTrue(result["data"]["removeRoleFromUser"]["ok"])
+        querystring = '''
+        {{
+          getUser(username: "{0}"){{
+            roles{{
+                edges{{ node {{ name }}}}
+                }}
+            }}
+        }}
+        '''.format(username).strip()
+        result = loads(self.client.execute(querystring))
+        self.assertEqual(0, len(result["data"]["getUser"]["roles"]["edges"]))
+
+
     def _create_role(self, name, description):
         querystring = '''
         mutation{{