Enable worker-multiplier on manila

This change draws on the charms.openstack and layer-openstack-api
changes to provide the ability to configure the number of workers that
the manila charm starts for API usage.

It also:
 * Packages the manila charm into a venv.  This is because the
   subordinate charms are ALSO reactive, which means that different
   versions of either charms.reactive or charms.openstack could be
   overwritten from the subordinate charm.
 * Band-aid an issue with manila-share not being started even though all
   of the config is properly set.  This uses the update-status hook to
   check to see if the manila-share service should be running.
   (Bug: #1706699)
 * Work-around for a bug in python-manilaclient (Bug: #1707303) which
   caused basic_deployment test 400 to fail.

Change-Id: I0ea0f14fb69bea5d2008ed70d72ba27c98c96679
Depends-On: I3cea350e536306655f5f109ec67ae7f0fba35fda
Depends-On: Id4145ffaa622727523003015d7012ece2f0eae4f
Related-Bug: #1677543
Partial-Bug: #1706699
Related-Bug: #1707303

src/layer.yaml

@@ -6,3 +6,7 @@ includes:
   - interface:neutron-plugin
   - interface:manila-plugin
 repo: https://github.com/openstack/charm-manila
+options:
+  basic:
+    use_venv: true
+    include_system_packages: true

src/reactive/manila_handlers.py

@@ -15,6 +15,9 @@
 # this is just for the reactive handlers and calls into the charm.
 from __future__ import absolute_import
 
+import charmhelpers.contrib.openstack.utils as os_utils
+import charmhelpers.core.host as ch_host
+
 import charms.reactive
 import charms_openstack.charm
 
@@ -28,16 +31,12 @@ charms_openstack.charm.use_defaults(
     'charm.installed',
     'amqp.connected',
     'shared-db.connected',
-    # 'identity-service.connected',
     'identity-service.available',  # enables SSL support
-    # 'config.changed',
-    'update-status'
 )
 
 
 @charms.reactive.when('identity-service.connected')
-@charms.reactive.when_not('identity-service.available',
-                          'update-status')
+@charms.reactive.when_not('identity-service.available')
 def register_endpoints(keystone):
     """Register the endpoints when the identity-service connects.
     Note that this charm doesn't use the default endpoint registration function
@@ -51,7 +50,6 @@ def register_endpoints(keystone):
 
 @charms.reactive.when('identity-service.connected',
                       'manila-plugin.connected')
-@charms.reactive.when_not('update-status')
 def share_to_manila_plugins_auth(keystone, manila_plugin, *args):
     """When we have the identity-service and (a) backend plugin, share the auth
     plugin with the back end.
@@ -81,7 +79,6 @@ def share_to_manila_plugins_auth(keystone, manila_plugin, *args):
 
 @charms.reactive.when('shared-db.available',
                       'manila.config.rendered')
-@charms.reactive.when_not('update-status')
 def maybe_do_syncdb(shared_db):
     """Sync the database when the shared-db becomes available.  Note that the
     charms.openstack.OpenStackCharm.db_sync() default method checks that only
@@ -96,7 +93,6 @@ def maybe_do_syncdb(shared_db):
 @charms.reactive.when('shared-db.available',
                       'identity-service.available',
                       'amqp.available')
-@charms.reactive.when_not('update-status')
 def render_stuff(*args):
     """Render the configuration for Manila when all the interfaces are
     available.
@@ -120,7 +116,6 @@ def render_stuff(*args):
                       'amqp.available')
 @charms.reactive.when_any('config-changed',
                           'manila-plugin.changed')
-@charms.reactive.when_not('update-status')
 def config_changed(*args):
     """When the configuration is changed, check that we have all the interfaces
     and then re-render all the configuration files.  Note that this means that
@@ -128,3 +123,25 @@ def config_changed(*args):
     available and STAY available.
     """
     render_stuff(*args)
+
+
+@charms.reactive.hook('update-status')
+def update_status():
+    """Use the update-status hook to check to see if we can restart the
+    manila-share service: (BUG#1706699).  The bug appears to be a race-hazard
+    but it's proving very difficult to track it down.
+
+    This is a band-aid to enable the charm to get into a working state once all
+    of the interfaces have joined, and the bug has been hit; otherwise the
+    charm stays "stuck" with the service not running.
+
+    Note, there is no need to actually call update_status as one of the other
+    handlers will activate it.
+    """
+    if not os_utils.is_unit_paused_set():
+        state, message = os_utils._ows_check_services_running(
+            services=['manila-share'],
+            ports=None)
+        if state == 'blocked':
+            # try to start the 'manila-share' service
+            ch_host.service_start('manila-share')

src/templates/mitaka/manila.conf

@@ -25,6 +25,8 @@ scheduler_driver = manila.scheduler.drivers.filter.FilterScheduler
 
 debug = {{ options.debug }}
 
+# Number of workers for OpenStack Share API service. (integer value)
+osapi_share_workers = {{ options.workers }}
 
 [cors]
 

src/tests/basic_deployment.py

@@ -430,7 +430,8 @@ class ManilaBasicDeployment(OpenStackAmuletDeployment):
         manila = manila_client.Client(session=self.keystone_demo.session,
                                       endpoint=manila_ep)
         # now just try a list the shares
-        manila.shares.list()
+        # NOTE(AJK) the 'search_opts={}' is to work around Bug#1707303
+        manila.shares.list(search_opts={})
         u.log.debug('OK')
 
     def test_900_restart_on_config_change(self):

unit_tests/test_manila_handlers.py

@@ -46,12 +46,7 @@ class TestRegisteredHooks(test_utils.TestRegisteredHooks):
                                    'amqp.available', )
             },
             'when_not': {
-                'register_endpoints': ('identity-service.available',
-                                       'update-status', ),
-                'config_changed': ('update-status', ),
-                'render_stuff': ('update-status', ),
-                'share_to_manila_plugins_auth': ('update-status', ),
-                'maybe_do_syncdb': ('update-status', ),
+                'register_endpoints': ('identity-service.available', ),
             },
             'when_any': {
                 'config_changed': ('config-changed',