Checked that a match was found when deriving equipment name

inventory_provider/tasks/worker.py

@@ -448,6 +448,7 @@ def reload_router_config(self, hostname):
 
 
 def _derive_router_hostnames(config):
+    logger = logging.getLogger(__name__)
     r = get_redis(config)
     junosspace_equipment = set()
     for k in r.keys('junosspace:*'):
@@ -460,8 +461,11 @@ def _derive_router_hostnames(config):
         m = re.match(
             'opsdb:interface_services:([^:]+):.*$',
             k.decode('utf-8'))
-        opsdb_equipment.add(m.group(1))
-
+        if m:
+            opsdb_equipment.add(m.group(1))
+        else:
+            logger.info("Unable to derive router name from %s" %
+                        k.decode('utf-8'))
     return junosspace_equipment & opsdb_equipment