Allow to decide between Nova-network and Neutron

Adds a heat.conf option to set the OpenStack component responsible for
networking, and makes heat-engine auto-discover the networking service
on start up if such option is not set.
Also adds a convenience method to Resource class to let resources decide
what networking service to use.

Implements blueprint discover-networking-service

Change-Id: If7121089068cc2d2774bedb73e4e252b520eb5b3

bin/heat-engine

@@ -46,12 +46,31 @@ gettextutils.install('heat', lazy=True)
 
 LOG = logging.getLogger('heat.engine')
 
+
+def discover_networking_service():
+    from heat.common import heat_keystoneclient as hkc
+
+    # create empty context
+    ctxt = hkc.context.RequestContext()
+    # create admin client
+    admin_client = hkc.KeystoneClient(ctxt).admin_client
+    services = admin_client.services.list()
+
+    if 'network' in [s.type for s in services]:
+        cfg.CONF.set_override('networking_service', 'neutron')
+    else:
+        cfg.CONF.set_override('networking_service', 'nova')
+
+
 if __name__ == '__main__':
 
     cfg.CONF(project='heat', prog='heat-engine')
     logging.setup('heat')
     messaging.setup()
 
+    if not cfg.CONF.networking_service:
+        discover_networking_service()
+
     from heat.engine import service as engine
 
     srv = engine.EngineService(cfg.CONF.host, rpc_api.ENGINE_TOPIC)

etc/heat/heat.conf.sample

@@ -73,6 +73,10 @@
 # Deprecated. (string value)
 #onready=<None>
 
+# Select OpenStack component responsible for networking - nova
+# or neutron. (string value)
+#networking_service=<None>
+
 
 #
 # Options defined in heat.common.config

heat/common/config.py

@@ -138,7 +138,11 @@ engine_opts = [
                help=_('RPC timeout for the engine liveness check that is used'
                       ' for stack locking.')),
     cfg.StrOpt('onready',
-               help=_('Deprecated.'))]
+               help=_('Deprecated.')),
+    cfg.StrOpt('networking_service',
+               choices=['nova', 'neutron'],
+               help=_('Select OpenStack component '
+                      'responsible for networking - nova or neutron.'))]
 
 rpc_opts = [
     cfg.StrOpt('host',

heat/engine/resource.py

@@ -1086,3 +1086,7 @@ class Resource(object):
             # force fetch all resource data from the database again
             self._data = None
             return True
+
+    @staticmethod
+    def is_using_neutron():
+        return cfg.CONF.networking_service == 'neutron'

heat/tests/test_resource.py

@@ -995,6 +995,15 @@ class ResourceTest(HeatTestCase):
                          TestResource.resource_to_template(
                              'Test::Resource::resource'))
 
+    def test_is_using_neutron(self):
+        snippet = rsrc_defn.ResourceDefinition('aresource',
+                                               'GenericResourceType')
+        res = resource.Resource('aresource', snippet, self.stack)
+        cfg.CONF.set_override('networking_service', 'neutron')
+        self.assertTrue(res.is_using_neutron())
+        cfg.CONF.set_override('networking_service', 'nova')
+        self.assertFalse(res.is_using_neutron())
+
 
 class ResourceAdoptTest(HeatTestCase):
     def setUp(self):