Add simple file loggin to ovs_quantum_agent.

Default behaviour is retained. Fix bug #1016232

Change-Id: If11244d48a5c966bbbf8786e3e9f42d205a70164

etc/quantum/plugins/openvswitch/ovs_quantum_plugin.ini

@@ -51,6 +51,8 @@ root_helper = sudo
 # integration_bridge = br-int
 # [AGENT]
 # root_helper = sudo
+# Add the following setting, if you want to log to a file
+# log_file = /var/log/quantum/ovs_quantum_agent.log
 #
 # 2. With tunneling.
 # [DATABASE]

quantum/plugins/openvswitch/agent/ovs_quantum_agent.py

@@ -523,6 +523,15 @@ def main():
     config_file = args[0]
     conf = config.parse(config_file)
 
+    if conf.AGENT.log_file:
+        # Avoid to redirect traces to stdout/stderr
+        logging.getLogger().handlers = []
+        handler = logging.FileHandler(conf.AGENT.log_file)
+        formatter = logging.Formatter('%(asctime)s %(levelname)s %(message)s')
+        handler.setFormatter(formatter)
+        LOG.addHandler(handler)
+        LOG.debug('Verbose: %s', options.verbose)
+
     # Determine which agent type to use.
     enable_tunneling = conf.OVS.enable_tunneling
     integ_br = conf.OVS.integration_bridge

quantum/plugins/openvswitch/common/config.py

@@ -34,6 +34,7 @@ ovs_opts = [
 agent_opts = [
     cfg.IntOpt('polling_interval', default=2),
     cfg.StrOpt('root_helper', default='sudo'),
+    cfg.StrOpt('log_file', default=None),
 ]