Merge "Make RPC implementation configurable"

mistral/cmd/launch.py

@@ -231,7 +231,6 @@ def get_properly_ordered_parameters():
 def main():
     try:
         config.parse_args(get_properly_ordered_parameters())
-
         print_server_info()
 
         logging.setup(CONF, 'Mistral')

mistral/config.py

@@ -46,6 +46,13 @@ api_opts = [
     )
 ]
 
+rpc_impl_opt = cfg.StrOpt(
+    'rpc_implementation',
+    default='oslo',
+    choices=['oslo', 'kombu'],
+    help='Specifies RPC implementation for RPC client and server.'
+)
+
 pecan_opts = [
     cfg.StrOpt(
         'root',
@@ -188,6 +195,7 @@ CONF.register_opts(execution_expiration_policy_opts,
 CONF.register_opt(wf_trace_log_name_opt)
 CONF.register_opts(coordination_opts, group=COORDINATION_GROUP)
 CONF.register_opts(profiler_opts, group=PROFILER_GROUP)
+CONF.register_opt(rpc_impl_opt)
 
 
 CLI_OPTS = [
@@ -224,6 +232,7 @@ def list_opts():
             CLI_OPTS,
             [
                 wf_trace_log_name_opt,
+                rpc_impl_opt
             ]
         ))
     ]

mistral/engine/rpc/rpc.py

@@ -19,6 +19,7 @@ import oslo_messaging as messaging
 from oslo_messaging.rpc import client
 from oslo_messaging.rpc import dispatcher
 from oslo_messaging.rpc import server
+from stevedore import driver
 
 from mistral import context as auth_ctx
 from mistral.engine import base
@@ -29,6 +30,8 @@ from mistral.workflow import utils as wf_utils
 LOG = logging.getLogger(__name__)
 
 
+_IMPL_CLIENT = None
+_IMPL_SERVER = None
 _TRANSPORT = None
 
 _ENGINE_CLIENT = None
@@ -84,6 +87,32 @@ def get_executor_client():
     return _EXECUTOR_CLIENT
 
 
+def get_rpc_server_driver():
+    rpc_impl = cfg.CONF.rpc_implementation
+
+    global _IMPL_SERVER
+    if not _IMPL_SERVER:
+        _IMPL_SERVER = driver.DriverManager(
+            'mistral.engine.rpc',
+            '%s_server' % rpc_impl
+        ).driver
+
+    return _IMPL_SERVER
+
+
+def get_rpc_client_driver():
+    rpc_impl = cfg.CONF.rpc_implementation
+
+    global _IMPL_CLIENT
+    if not _IMPL_CLIENT:
+        _IMPL_CLIENT = driver.DriverManager(
+            'mistral.engine.rpc',
+            '%s_client' % rpc_impl
+        ).driver
+
+    return _IMPL_CLIENT
+
+
 class EngineServer(object):
     """RPC Engine server."""
 

setup.cfg

@@ -40,6 +40,12 @@ console_scripts =
     mistral-server = mistral.cmd.launch:main
     mistral-db-manage = mistral.db.sqlalchemy.migration.cli:main
 
+mistral.engine.rpc =
+    oslo_client = mistral.engine.rpc.oslo.oslo_client:OsloRPCClient
+    oslo_server = mistral.engine.rpc.oslo.oslo_server:OsloRPCServer
+    kombu_client = mistral.engine.rpc.kombu.kombu_client:KombuRPCClient
+    kombu_server = mistral.engine.rpc.kombu.kombu_server:KombuRPCServer
+
 oslo.config.opts =
     mistral.config = mistral.config:list_opts