Added a instance state update notification

Added a instance update notification (compute.instance.update) that
will report on changes to vm_state and task_state. The goal here is
to provide useful insight into instance state transitions.  (e.g.
BUILDING->ACTIVE)

The new notification has minimial dependencies and is intended for
wide use across the different layers/packages within nova.  Calls
in compute api/manager, scheduler, and the virt layer that modify
the instance state have been instrumented with this notification.

Change-Id: I223eb7eccc8aa079b782f6bb17727cd0b71d18ed

3 files changed, 35 insertions, 90 deletions

diff --git a/nova/compute/api.py b/nova/compute/api.py
index e83dfb3a6..3fd358a34 100644
--- a/nova/compute/api.py
+++ b/nova/compute/api.py
@@ -41,6 +41,7 @@ from nova import flags
 import nova.image
 from nova import log as logging
 from nova import network
+from nova import notifications
 from nova.openstack.common import cfg
 from nova.openstack.common import excutils
 from nova.openstack.common import jsonutils
@@ -599,6 +600,11 @@ class API(base.Base):
         instance_id = instance['id']
         instance_uuid = instance['uuid']
 
+        # send a state update notification for the initial create to
+        # show it going from non-existent to BUILDING
+        notifications.send_update_with_states(context, instance, None,
+                vm_states.BUILDING, None, None)
+
         for security_group_id in security_groups:
             self.db.instance_add_security_group(elevated,
                                                 instance_uuid,
@@ -919,8 +925,14 @@ class API(base.Base):
 
         :returns: None
         """
-        rv = self.db.instance_update(context, instance["id"], kwargs)
-        return dict(rv.iteritems())
+
+        # Update the instance record and send a state update notification
+        # if task or vm state changed
+        old_ref, instance_ref = self.db.instance_update_and_get_original(
+                context, instance["id"], kwargs)
+        notifications.send_update(context, old_ref, instance_ref)
+
+        return dict(instance_ref.iteritems())
 
     @wrap_check_policy
     @check_instance_state(vm_state=[vm_states.ACTIVE, vm_states.SHUTOFF,
@@ -1260,9 +1272,16 @@ class API(base.Base):
         else:
             raise Exception(_('Image type not recognized %s') % image_type)
 
+        # change instance state and notify
+        old_vm_state = instance["vm_state"]
+        old_task_state = instance["task_state"]
+
         self.db.instance_test_and_set(
                 context, instance_uuid, 'task_state', [None], task_state)
 
+        notifications.send_update_with_states(context, instance, old_vm_state,
+                instance["vm_state"], old_task_state, instance["task_state"])
+
         properties = {
             'instance_uuid': instance_uuid,
             'user_id': str(context.user_id),
diff --git a/nova/compute/manager.py b/nova/compute/manager.py
index bd3cd02cc..6a0251a15 100644
--- a/nova/compute/manager.py
+++ b/nova/compute/manager.py
@@ -61,6 +61,7 @@ from nova import log as logging
 from nova import manager
 from nova import network
 from nova.network import model as network_model
+from nova import notifications
 from nova.notifier import api as notifier
 from nova.openstack.common import cfg
 from nova.openstack.common import excutils
@@ -253,7 +254,12 @@ class ComputeManager(manager.SchedulerDependentManager):
 
     def _instance_update(self, context, instance_id, **kwargs):
         """Update an instance in the database using kwargs as value."""
-        return self.db.instance_update(context, instance_id, kwargs)
+
+        (old_ref, instance_ref) = self.db.instance_update_and_get_original(
+                context, instance_id, kwargs)
+        notifications.send_update(context, old_ref, instance_ref)
+
+        return instance_ref
 
     def _set_instance_error_state(self, context, instance_uuid):
         try:
diff --git a/nova/compute/utils.py b/nova/compute/utils.py
index 7a6ac8671..ab5ccfbf0 100644
--- a/nova/compute/utils.py
+++ b/nova/compute/utils.py
@@ -25,6 +25,7 @@ from nova import flags
 from nova import log
 from nova import network
 from nova.network import model as network_model
+from nova import notifications
 from nova.notifier import api as notifier_api
 from nova import utils
 
@@ -52,45 +53,10 @@ def notify_usage_exists(context, instance_ref, current_period=False,
         override in the notification if not None.
     """
 
-    admin_context = nova.context.get_admin_context(read_deleted='yes')
-    begin, end = utils.last_completed_audit_period()
-    bw = {}
-    if current_period:
-        audit_start = end
-        audit_end = utils.utcnow()
-    else:
-        audit_start = begin
-        audit_end = end
-
-    if (instance_ref.get('info_cache') and
-        instance_ref['info_cache'].get('network_info')):
-
-        cached_info = instance_ref['info_cache']['network_info']
-        nw_info = network_model.NetworkInfo.hydrate(cached_info)
-    else:
-        try:
-            nw_info = network.API().get_instance_nw_info(admin_context,
-                                                         instance_ref)
-        except Exception:
-            LOG.exception('Failed to get nw_info', instance=instance_ref)
-            if ignore_missing_network_data:
-                return
-            raise
-
-    macs = [vif['address'] for vif in nw_info]
-    uuids = [instance_ref.uuid]
-
-    bw_usages = db.bw_usage_get_by_uuids(admin_context, uuids, audit_start)
-    bw_usages = [b for b in bw_usages if b.mac in macs]
-
-    for b in bw_usages:
-        label = 'net-name-not-found-%s' % b['mac']
-        for vif in nw_info:
-            if vif['address'] == b['mac']:
-                label = vif['network']['label']
-                break
+    audit_start, audit_end = notifications.audit_period_bounds(current_period)
 
-        bw[label] = dict(bw_in=b.bw_in, bw_out=b.bw_out)
+    bw = notifications.bandwidth_usage(instance_ref, audit_start,
+            ignore_missing_network_data)
 
     if system_metadata is None:
         try:
@@ -100,10 +66,7 @@ def notify_usage_exists(context, instance_ref, current_period=False,
             system_metadata = {}
 
     # add image metadata to the notification:
-    image_meta = {}
-    for md_key, md_value in system_metadata.iteritems():
-        if md_key.startswith('image_'):
-            image_meta[md_key[6:]] = md_value
+    image_meta = notifications.image_meta(system_metadata)
 
     extra_info = dict(audit_period_beginning=str(audit_start),
                       audit_period_ending=str(audit_end),
@@ -231,49 +194,6 @@ def legacy_network_info(network_model):
     return network_info
 
 
-def _usage_from_instance(context, instance_ref, network_info,
-        system_metadata, **kw):
-    """
-    Get usage information for an instance which is common to all
-    notifications.
-
-    :param network_info: network_info provided if not None
-    :param system_metadata: system_metadata DB entries for the instance,
-        if not None.  *NOTE*: Currently unused here in trunk, but needed for
-        potential custom modifications.
-    """
-
-    def null_safe_str(s):
-        return str(s) if s else ''
-
-    image_ref_url = utils.generate_image_url(instance_ref['image_ref'])
-
-    usage_info = dict(
-          tenant_id=instance_ref['project_id'],
-          user_id=instance_ref['user_id'],
-          instance_id=instance_ref['uuid'],
-          instance_type=instance_ref['instance_type']['name'],
-          instance_type_id=instance_ref['instance_type_id'],
-          memory_mb=instance_ref['memory_mb'],
-          disk_gb=instance_ref['root_gb'] + instance_ref['ephemeral_gb'],
-          display_name=instance_ref['display_name'],
-          created_at=str(instance_ref['created_at']),
-          # Nova's deleted vs terminated instance terminology is confusing,
-          # this should be when the instance was deleted (i.e. terminated_at),
-          # not when the db record was deleted. (mdragon)
-          deleted_at=null_safe_str(instance_ref['terminated_at']),
-          launched_at=null_safe_str(instance_ref['launched_at']),
-          image_ref_url=image_ref_url,
-          state=instance_ref['vm_state'],
-          state_description=null_safe_str(instance_ref['task_state']))
-
-    if network_info is not None:
-        usage_info['fixed_ips'] = network_info.fixed_ips()
-
-    usage_info.update(kw)
-    return usage_info
-
-
 def notify_about_instance_usage(context, instance, event_suffix,
                                 network_info=None, system_metadata=None,
                                 extra_usage_info=None, host=None):
@@ -296,8 +216,8 @@ def notify_about_instance_usage(context, instance, event_suffix,
     if not extra_usage_info:
         extra_usage_info = {}
 
-    usage_info = _usage_from_instance(context, instance, network_info,
-            system_metadata, **extra_usage_info)
+    usage_info = notifications.usage_from_instance(context, instance,
+            network_info, system_metadata, **extra_usage_info)
 
     notifier_api.notify(context, 'compute.%s' % host,
                         'compute.instance.%s' % event_suffix,