Merge lp:~blr/charms/precise/squid-forwardproxy/rutabaga-auth-helper into lp:~canonical-launchpad-branches/charms/precise/squid-forwardproxy/trunk

[Kit Randel]

* Add wait_for_auth_helper config value, allowing delayed config_changed hook until auth-helper-relation-joined.
* Remove 'run' config.

[lp:~blr/charms/precise/squid-forwardproxy/rutabaga-auth-helper]

52. By Kit Randel on 2015-11-30

Rename auth-helper to squid-auth-helper.

53. By Kit Randel on 2015-11-30

Avoid mutating state of wait_for_auth_helper.

54. By Kit Randel on 2015-12-01

Prevent config parsing if not STATE_STARTED.

55. By Kit Randel on 2015-12-01

Update service ports independantly of configuration parsing in config_changed().

56. By Kit Randel on 2015-12-01

Set initial HOOK_START value to False.

[Colin Watson (cjwatson)]

review: Approve

[lp:~blr/charms/precise/squid-forwardproxy/rutabaga-auth-helper]

57. By Kit Randel on 2015-12-03

Add logging...

58. By Kit Randel on 2015-12-03

* Remove juju/general-info relations
* Add additional auth-helper relation symlinks.

59. By Kit Randel on 2015-12-06

Only squid-auth-helper-relation-joined implemented.

60. By Kit Randel on 2015-12-06

Manage hook state more consistently.

=== modified file 'config.yaml'
--- config.yaml	2015-09-16 02:59:55 +0000
+++ config.yaml	2015-12-06 22:48:44 +0000
@@ -47,13 +47,6 @@
     type: int
     default: 8192
     description: Maximum size of an object to be cached (KB).
-  run:
-    type: boolean
-    default: true
-    description: >
-      Run state of squid service. A value of false will stop the service currently running, or prevent
-      the service starting on installation. This is potentially useful for awaiting deployment
-      of a sub-ordinate helper service.
   snmp_community:
     type: string
     default: ''
@@ -64,6 +57,12 @@
     default: ''
     description: Single, or json-formatted list of, IP (with optional subnet mask) allowed to query SNMP.
     # validator: '[0-9a-zA-z]{6,32}'
+  wait_for_auth_helper:
+    type: boolean
+    default: false
+    description: >
+      If True, squid will not be started until an squid-auth-helper relation is joined. This is needed as
+      Squid will fail to start if a defined auth_helper program is not available. 
   nagios_context:
     default: "juju"
     type: string

=== modified file 'hooks/hooks.py'
--- hooks/hooks.py	2015-09-17 22:30:08 +0000
+++ hooks/hooks.py	2015-12-06 22:48:44 +0000
@@ -22,7 +22,9 @@
 default_squid3_config = "%s/squid.conf" % default_squid3_config_dir
 default_squid3_config_cache_dir = "/var/run/squid3"
 hook_name = os.path.basename(sys.argv[0])
-
+HOOK_START = False
+HOOK_AUTH_HELPER_JOINED = False
+STATE_DELAYED_START = False
 ###############################################################################
 # Supporting functions
 ###############################################################################
@@ -315,7 +317,9 @@
     if action is None or squid3_config is None:
         return(None)
     elif action == "check":
-        retVal = subprocess.call(['/usr/sbin/squid3', '-f', squid3_config, '-k', 'parse'])
+        utils.juju_log('INFO', 'Checking squid3 configuration...')
+        retVal = subprocess.call(
+            ['/usr/sbin/squid3', '-f', squid3_config, '-k', 'parse'])
         if retVal == 1:
             return(False)
         elif retVal == 0:
@@ -397,17 +401,21 @@
 
 
 def config_changed():
-    config_data = config_get()
-    if not config_data['run']:
-        return(service_squid3('stop'))
-
     current_service_ports = get_service_ports()
     construct_squid3_config()
     update_nrpe_checks()
 
+    updated_service_ports = get_service_ports()
+    update_service_ports(current_service_ports, updated_service_ports)
+
+    config_data = config_get()
+    if config_data['wait_for_auth_helper'] and not STATE_DELAYED_START:
+        # unable to parse squid3 configuration without auth helper in
+        # place.
+        utils.juju_log('INFO', 'Squid not started, waiting for auth helper...')
+        return
+
     if service_squid3('check'):
-        updated_service_ports = get_service_ports()
-        update_service_ports(current_service_ports, updated_service_ports)
         if service_squid3('status'):
             service_squid3('reload')
         else:
@@ -416,10 +424,27 @@
         sys.exit(1)
 
 
-def start_hook():
+def start_hook(start=None, auth_helper=None):
+    global HOOK_START
+    global HOOK_AUTH_HELPER_JOINED
+
+    if start:
+        HOOK_START = True
+    if auth_helper:
+        HOOK_AUTH_HELPER_JOINED = True
+
     config_data = config_get()
-    if not config_data['run']:
-        return
+    if config_data['wait_for_auth_helper']:
+        if HOOK_AUTH_HELPER_JOINED and HOOK_START:
+            utils.juju_log('INFO', 'Squid auth helper available, starting...')
+            if service_squid3('check'):
+                STATE_DELAYED_START = True
+            else:
+                sys.exit(1)
+        else:
+            utils.juju_log('INFO', 'Waiting for auth helper...')
+            return
+
     if service_squid3("status"):
         return(service_squid3("restart"))
     else:
@@ -449,10 +474,11 @@
     elif hook_name == "config-changed":
         config_changed()
     elif hook_name == "start":
-        start_hook()
+        start_hook(start=True)
     elif hook_name == "stop":
         stop_hook()
-
+    elif hook_name == "squid-auth-helper-relation-joined":
+        start_hook(auth_helper=True)
     elif hook_name == "cached-website-relation-joined":
         proxy_interface("joined")
     elif hook_name == "cached-website-relation-changed":

=== added symlink 'hooks/squid-auth-helper-relation-joined'
=== target is u'hooks.py'
=== modified file 'metadata.yaml'
--- metadata.yaml	2013-07-11 19:15:19 +0000
+++ metadata.yaml	2015-12-06 22:48:44 +0000
@@ -14,6 +14,10 @@
     sitenames: space-delimited list of vhosts to whitelist
 categories:
     - cache-proxy
+requires:
+  squid-auth-helper:
+    interface: squid-auth-helper
+    optional: true
 provides:
   cached-website:
     interface: http