heat-all: all-in-one heat launcher

This patch implements a new heat-all command that can be used
to launch a single process version of the configured heat services.
The end user can control which services are launched by setting
'enabled_services' in the heat config file:

[heat_all]
  enabled_services = api,engine

One use case for this launcher would be to launch a single process heat
using rpc_backend = fake, connection=sqlite://heat.db, to have access
to a minimal all in one Heat API/Engine for TripleO undercloud
deployments via Heat templates.

Change-Id: Ic35bdc455fe1397ac575522af0c8fca96dd95676

1 files changed, 11 insertions, 4 deletions

diff --git a/heat/cmd/engine.py b/heat/cmd/engine.py
index d3858943a..41cf8008a 100644
--- a/heat/cmd/engine.py
+++ b/heat/cmd/engine.py
@@ -44,12 +44,14 @@ i18n.enable_lazy()
 LOG = logging.getLogger('heat.engine')
 
 
-def main():
-    logging.register_options(cfg.CONF)
+def launch_engine(setup_logging=True):
+    if setup_logging:
+        logging.register_options(cfg.CONF)
     cfg.CONF(project='heat', prog='heat-engine',
              version=version.version_info.version_string())
-    logging.setup(cfg.CONF, 'heat-engine')
-    logging.set_defaults()
+    if setup_logging:
+        logging.setup(cfg.CONF, 'heat-engine')
+        logging.set_defaults()
     messaging.setup()
 
     config.startup_sanity_check()
@@ -76,4 +78,9 @@ def main():
         # We create the periodic tasks here, which mean they are created
         # only in the parent process when num_engine_workers>1 is specified
         srv.create_periodic_tasks()
+    return launcher
+
+
+def main():
+    launcher = launch_engine()
     launcher.wait()