Refactor resource dependencies

This refactors resource dependencies to improve the following points.

 - Avoid unnecessary dependencies across services. For example aodh
   service does not require cinder db.

 - Restart only api service when config files like paste.ini, which
   are used only be api service is changed.

Change-Id: Id4916244bdf4cd4ff2b45a45ec3e25fb0d115249

manifests/api.pp

@@ -218,6 +218,11 @@ class nova::api(
       'DEFAULT/enabled_apis': value => join(any2array($enabled_apis), ',');
     }
     $service_enabled = $enabled
+
+    if $manage_service {
+      Nova_api_paste_ini<||> ~> Service['nova-api']
+      Nova_api_uwsgi_config<||> ~> Service['nova-api']
+    }
   } elsif $service_name == 'httpd' {
     nova_config {
       'DEFAULT/enabled_apis': ensure => absent;
@@ -238,6 +243,8 @@ class nova::api(
       if $metadata_service_name {
         Service['nova-api-metadata'] -> Service[$service_name]
       }
+
+      Nova_api_paste_ini<||> ~> Service[$service_name]
     }
   } else {
     fail("Invalid service_name. Either nova-api/openstack-nova-api for running \
@@ -253,6 +260,9 @@ as a standalone service, or httpd for being run by a httpd server")
   }
 
   if $metadata_service_name {
+    if $manage_service {
+      Nova_api_metadata_uwsgi_config<||> ~> Service['nova-api-metadata']
+    }
     nova::generic_service { 'api-metadata':
       enabled        => $service_enabled,
       manage_service => $manage_service,

manifests/cache.pp

@@ -243,4 +243,8 @@ class nova::cache (
     hashclient_retry_delay               => $hashclient_retry_delay,
     dead_timeout                         => $dead_timeout,
   }
+
+  # all cache settings should be applied and all packages should be installed
+  # before service startup
+  Oslo::Cache['nova_config'] -> Anchor['nova::service::begin']
 }

manifests/db.pp

@@ -145,4 +145,10 @@ class nova::db (
     max_overflow            => $api_database_max_overflow,
     pool_timeout            => $api_database_pool_timeout,
   }
+
+  # all db settings should be applied and all packages should be installed
+  # before dbsync starts
+  Oslo::Db['nova_config'] -> Anchor['nova::dbsync::begin']
+  Oslo::Db['api_database'] -> Anchor['nova::dbsync::begin']
+  Oslo::Db['api_database'] -> Anchor['nova::dbsync_api::begin']
 }

manifests/deps.pp

@@ -24,30 +24,21 @@ class nova::deps {
   ~> Service<| tag == 'nova-service' |>
   ~> anchor { 'nova::service::end': }
 
-  # paste-api.ini config should occur in the config block also.
   Anchor['nova::config::begin']
   -> Nova_api_paste_ini<||>
-  ~> Anchor['nova::config::end']
+  -> Anchor['nova::config::end']
 
-  # rootwrap config should occur in the config block also.
   Anchor['nova::config::begin']
   -> Nova_rootwrap_config<||>
   ~> Anchor['nova::config::end']
 
-  # policy config should occur in the config block also.
-  Anchor['nova::config::begin']
-  -> Openstacklib::Policy<| tag == 'nova' |>
-  -> Anchor['nova::config::end']
-
-  # On any uwsgi config change, we must restart Nova APIs.
   Anchor['nova::config::begin']
   -> Nova_api_uwsgi_config<||>
-  ~> Anchor['nova::config::end']
+  -> Anchor['nova::config::end']
 
   Anchor['nova::config::begin']
   -> Nova_api_metadata_uwsgi_config<||>
-  ~> Anchor['nova::config::end']
-
+  -> Anchor['nova::config::end']
 
   # Support packages need to be installed in the install phase, but we don't
   # put them in the chain above because we don't want any false dependencies
@@ -84,15 +75,6 @@ class nova::deps {
   Anchor['nova::config::begin'] -> Virtstoraged_config<||> -> Anchor['nova::config::end']
   Anchor['nova::config::begin'] -> Qemu_config<||> -> Anchor['nova::config::end']
 
-  # all cache settings should be applied and all packages should be installed
-  # before service startup
-  Oslo::Cache<||> -> Anchor['nova::service::begin']
-
-  # all db settings should be applied and all packages should be installed
-  # before dbsync starts
-  Oslo::Db<||> -> Anchor['nova::dbsync::begin']
-  Oslo::Db<||> -> Anchor['nova::dbsync_api::begin']
-
   # Installation or config changes will always restart services.
   Anchor['nova::install::end'] ~> Anchor['nova::service::begin']
   Anchor['nova::config::end']  ~> Anchor['nova::service::begin']

manifests/keystone/authtoken.pp

@@ -279,4 +279,6 @@ class nova::keystone::authtoken(
       service_type                   => $service_type,
       interface                      => $interface;
   }
+
+  Keystone::Resource::Authtoken['nova_config'] -> Anchor['nova::config::end']
 }

manifests/policy.pp

@@ -70,6 +70,11 @@ class nova::policy (
 
   create_resources('openstacklib::policy', { $policy_path => $policy_parameters })
 
+  # policy config should occur in the config block also.
+  Anchor['nova::config::begin']
+  -> Openstacklib::Policy[$policy_path]
+  -> Anchor['nova::config::end']
+
   oslo::policy { 'nova_config':
     enforce_scope        => $enforce_scope,
     enforce_new_defaults => $enforce_new_defaults,