Initialize RPC-related flag when starting API

Closes-Bug:1602003

Change-Id: Idf08ce2a5eaa8b7c740b6dc09af29ca48cbc8bab

mistral/api/app.py

@@ -23,6 +23,7 @@ from mistral import config as m_config
 from mistral import context as ctx
 from mistral import coordination
 from mistral.db.v2 import api as db_api_v2
+from mistral.engine.rpc_backend import rpc
 from mistral.services import periodic
 
 
@@ -67,6 +68,9 @@ def setup_app(config=None):
     # Set up access control.
     app = access_control.setup(app)
 
+    # Set up RPC related flags in config
+    rpc.get_transport()
+
     # Set up profiler.
     if cfg.CONF.profiler.enabled:
         app = osprofiler.web.WsgiMiddleware(