restart_on_stop Ticket: [SOL-950]

- Added restart_on_stop decorator function which starts plumgrid service is it has been stopped in the function
- Added restart_on_change to config-changed hook so that any config changes result in plugrid restart
- ifc_list_gateway only removed when change in ifcs.conf

hooks/pg_gw_hooks.py

@@ -14,8 +14,6 @@ from charmhelpers.core.hookenv import (
     config,
 )
 
-from charmhelpers.core.host import service_running
-
 from charmhelpers.fetch import (
     apt_install,
     configure_sources,
@@ -24,7 +22,6 @@ from charmhelpers.fetch import (
 from pg_gw_utils import (
     register_configs,
     ensure_files,
-    restart_pg,
     restart_map,
     stop_pg,
     determine_packages,
@@ -35,6 +32,7 @@ from pg_gw_utils import (
     fabric_interface_changed,
     load_iptables,
     restart_on_change,
+    restart_on_stop,
     director_cluster_ready
 )
 
@@ -71,6 +69,8 @@ def plumgrid_changed():
 
 
 @hooks.hook('config-changed')
+@restart_on_stop()
+@restart_on_change(restart_map())
 def config_changed():
     '''
     This hook is run when a config parameter is changed.
@@ -83,10 +83,6 @@ def config_changed():
     if charm_config.changed('fabric-interfaces'):
         if not fabric_interface_changed():
             log("Fabric interface already set")
-        else:
-            stop_pg()
-    if charm_config.changed('external-interfaces'):
-        stop_pg()
     if (charm_config.changed('install_sources') or
         charm_config.changed('plumgrid-build') or
         charm_config.changed('install_keys') or
@@ -100,8 +96,6 @@ def config_changed():
             load_iovisor()
     ensure_mtu()
     CONFIGS.write_all()
-    if not service_running('plumgrid'):
-        restart_pg()
 
 
 @hooks.hook('upgrade-charm')

hooks/pg_gw_utils.py

@@ -393,6 +393,19 @@ def director_cluster_ready():
     return True if dirs_count == 1 or dirs_count == 3 else False
 
 
+def restart_on_stop():
+    """
+    Starts plumgrid service if it is stopped
+    """
+    def wrap(f):
+        def wrapped_f(*args, **kwargs):
+            f(*args, **kwargs)
+            if not service_running('plumgrid'):
+                restart_pg()
+        return wrapped_f
+    return wrap
+
+
 def restart_on_change(restart_map):
     """
     Restart services based on configuration files changing
@@ -403,6 +416,8 @@ def restart_on_change(restart_map):
             f(*args, **kwargs)
             for path in restart_map:
                 if path_hash(path) != checksums[path]:
+                    if path == PG_IFCS_CONF:
+                        ensure_files()
                     restart_pg()
                     break
         return wrapped_f

unit_tests/test_pg_gw_hooks.py

@@ -24,7 +24,6 @@ TO_PATCH = [
     'configure_sources',
     'ensure_files',
     'stop_pg',
-    'restart_pg',
     'load_iovisor',
     'ensure_mtu',
     'add_lcm_key',