Enable retries when sending notifications

This patch enables retries when a connection error occurred
at the time of sending a notification.

This patch introduces a new config parameter
v2_vnfm.notify_connect_retries that specifies the maximum number
of retries. Note that the period between retries is exponential
starting 0.5 seconds up to a maximum of 60 seconds.

Change-Id: Ie75a7d1ec7a8dd8970b1cf58cff86f699bcc3311

tacker/sol_refactored/common/config.py

@@ -16,24 +16,28 @@
 
 from oslo_config import cfg
 
+from tacker._i18n import _
+
+
 CONF = cfg.CONF
 
 VNFM_OPTS = [
     cfg.StrOpt('endpoint',
                default='http://127.0.0.1:9890',
-               help='Endpoint of VNFM (self).'),
+               help=_('Endpoint of VNFM (self).')),
     cfg.IntOpt('default_graceful_termination_timeout',
                default=10,
-               help='Default timeout value (second) of GRACEFUL termination.'),
+               help=_('Default timeout value (second) of GRACEFUL '
+                      'termination.')),
     cfg.IntOpt('max_content_length',
                default=1000000,
-               help='Max content length for list APIs.'),
+               help=_('Max content length for list APIs.')),
     cfg.IntOpt('openstack_vim_stack_create_timeout',
                default=20,
-               help='Timeout (in minuts) of heat stack creation.'),
+               help=_('Timeout (in minuts) of heat stack creation.')),
     cfg.IntOpt('kubernetes_vim_rsc_wait_timeout',
                default=500,
-               help='Timeout (second) of k8s res creation.'),
+               help=_('Timeout (second) of k8s res creation.')),
     cfg.IntOpt('vnf_instance_page_size',
                default=0,  # 0 means no paging
                help=_('Paged response size of the query result '
@@ -46,6 +50,12 @@ VNFM_OPTS = [
                default=0,  # 0 means no paging
                help=_('Paged response size of the query result '
                       'for VNF LCM operation occurrences.')),
+    cfg.IntOpt('notify_connect_retries',
+               default=0,  # 0 means no retry
+               help=_('Number of retries that should be attempted for '
+                      'connection error when sending a notification. '
+                      'Period between retries is exponential starting '
+                      '0.5 seconds up to a maximum of 60 seconds.')),
     # NOTE: This is for test use since it is convenient to be able to delete
     # under development.
     cfg.BoolOpt('test_enable_lcm_op_occ_delete',
@@ -63,32 +73,33 @@ NFVO_OPTS = [
                        'use internal NFVO in tacker if False')),
     cfg.StrOpt('grant_api_version',
                default='1.4.0',  # SOL003 v3.3.1 9.1a
-               help='Grant api_version of NFVO.'),
+               help=_('Grant api_version of NFVO.')),
     cfg.StrOpt('vnfpkgm_api_version',
                default='2.1.0',  # SOL003 v3.3.1 10.1a
-               help='Vnf package management api_version of NFVO.'),
+               help=_('Vnf package management api_version of NFVO.')),
     # The following four parameters are for external NFVO.
     # Must be set when using external NFVO.
     # NOTE: It is assumed the VNFM communicates only one NFVO. That is
     # the same NFVO provides both the grant and vnf package management APIs.
     cfg.StrOpt('endpoint',
                default='',
-               help='Endpoint of external NFVO.'),
+               help=_('Endpoint of external NFVO.')),
     cfg.StrOpt('token_endpoint',
                default='',
-               help='Token endpoint for OAuth2.0 authentication.'),
+               help=_('Token endpoint for OAuth2.0 authentication.')),
     cfg.StrOpt('client_id',
                default='',
-               help='Client id used by OAuth2.0 authentication.'),
+               help=_('Client id used by OAuth2.0 authentication.')),
     cfg.StrOpt('client_password',
                default='',
-               help='Client password used by OAuth2.0 authentication.'),
+               help=_('Client password used by OAuth2.0 authentication.')),
     cfg.BoolOpt('test_callback_uri',
                 default=True,
-                help='Check to get notification from callback Uri.'),
+                help=_('Check to get notification from callback Uri.')),
     cfg.ListOpt('test_grant_zone_list',
                 default=["nova"],
-                help='Zones used for test which returned in Grant response.')
+                help=_('Zones used for test which returned in Grant '
+                       'response.'))
 ]
 
 CONF.register_opts(NFVO_OPTS, 'v2_nfvo')

tacker/sol_refactored/common/subscription_utils.py

@@ -76,8 +76,11 @@ def async_call(func):
 @async_call
 def send_notification(subsc, notif_data):
     auth_handle = _get_notification_auth_handle(subsc)
+    connect_retries = (CONF.v2_vnfm.notify_connect_retries
+        if CONF.v2_vnfm.notify_connect_retries else None)
     client = http_client.HttpClient(auth_handle,
-        version=api_version.CURRENT_VERSION)
+        version=api_version.CURRENT_VERSION,
+        connect_retries=connect_retries)
 
     url = subsc.callbackUri
     try: