[WORKER] Support PING message

This change prepares the code to support a separation of the ping
functionality and a new statistics gathering call. This change will
see either the STATS action or the PING action as the same, so both
will be supported for the time being. Eventually, the STATS action
will have a different meaning and return info like bytes output.

Change-Id: Ib86893725818ce0e6fa57c0bb01ec6df56e4d48a

libra/worker/controller.py

@@ -69,7 +69,10 @@ class LBaaSController(object):
             elif action == 'ARCHIVE':
                 return self._action_archive()
             elif action == 'STATS':
-                return self._action_stats()
+                # TODO: Implement new STATS function
+                return self._action_ping()
+            elif action == 'PING':
+                return self._action_ping()
             elif action == 'DIAGNOSTICS':
                 return self._action_diagnostic()
             else:
@@ -438,29 +441,28 @@ class LBaaSController(object):
             self.msg[self.RESPONSE_FIELD] = self.RESPONSE_SUCCESS
         return self.msg
 
-    def _action_stats(self):
+    def _action_ping(self):
         """
-        Get load balancer statistics.
+        Get load balancer and node status.
 
         We push responsibility for knowing what state a load balancer
-        current is in to the driver. Trying to get statistics for a LB that
+        current is in to the driver. Trying to get status for a LB that
         has been deleted is an error.
         """
 
         try:
-            # TODO: Do something with the returned statistics
+            stats = self.driver.get_status()
-            stats = self.driver.get_stats()
         except NotImplementedError:
-            error = "Selected driver does not support STATS action."
+            error = "Selected driver does not support PING action."
             self.logger.error(error)
             self.msg[self.RESPONSE_FIELD] = self.RESPONSE_FAILURE
             self.msg[self.ERROR_FIELD] = error
         except DeletedStateError:
-            self.logger.info("Invalid operation STATS on a deleted LB")
+            self.logger.info("Invalid operation PING on a deleted LB")
             self.msg['status'] = 'DELETED'
             self.msg[self.RESPONSE_FIELD] = self.RESPONSE_FAILURE
         except Exception as e:
-            self.logger.error("STATS failed: %s, %s" % (e.__class__, e))
+            self.logger.error("PING failed: %s, %s" % (e.__class__, e))
             self.msg[self.RESPONSE_FIELD] = self.RESPONSE_FAILURE
             self.msg[self.ERROR_FIELD] = str(e)
         else:

libra/worker/drivers/base.py

@@ -96,8 +96,8 @@ class LoadBalancerDriver(object):
         """ Delete a load balancer. """
         raise NotImplementedError()
 
-    def get_stats(self, protocol):
+    def get_status(self, protocol):
-        """ Get load balancer statistics for specified protocol. """
+        """ Get load balancer status for specified protocol. """
         raise NotImplementedError()
 
     def archive(self, method, params):

libra/worker/drivers/haproxy/driver.py

@@ -393,8 +393,8 @@ class HAProxyDriver(LoadBalancerDriver):
         # restart, otherwise the log file will be kept open and not reappear.
         self.ossvc.syslog_restart()
 
-    def get_stats(self, protocol=None):
+    def get_status(self, protocol=None):
-        return self.ossvc.get_stats(protocol)
+        return self.ossvc.get_status(protocol)
 
     def archive(self, method, params):
         """

libra/worker/drivers/haproxy/ubuntu_services.py

@@ -146,9 +146,9 @@ class UbuntuServices(ServicesBase):
         self.sudo_rm(self._config_file)
         self.sudo_rm(self._backup_config)
 
-    def get_stats(self, protocol=None):
+    def get_status(self, protocol=None):
         """
-        Query HAProxy socket for stats on the given protocol.
+        Query HAProxy socket for node status on the given protocol.
 
         protocol
             One of the supported protocol names (http or tcp).