use just once during upgradedb otherwise frontend's request processing

is out of application context

From docs: Setting a SERVER_NAME also by default enables URL generation
without a request context but with an application context.

module_build_service/manage.py

@@ -100,6 +100,7 @@ def testpdc():
 def upgradedb():
     """ Upgrades the database schema to the latest revision
     """
+    app.config["SERVER_NAME"] = 'localhost'
     # TODO: configurable?
     migrations_dir = os.path.join(os.path.abspath(os.path.dirname(__file__)),
                                   'migrations')