Alarm API does not validate schema in alarm_actions

[Rikimaru Honjo]

Currently, alarm API does not validate schema in alarm_actions.
When invalid schema is specified, error occurs later in alarm notifier.
Schema should be validated in advance in API.

Reproduce:
1.For example, an alarm with alarm_actions is set to 'spam://localhost:80/alarm', where the schema 'spam' is invalid, can be defined.

$ curl -v -X POST -H 'X-Auth-Token:bd8659bcc3154eeaa895e4a765de02b0' -H 'Content-type: application/json' -d '{"alarm_actions": ["spam://localhost:80/alarm"], "name": "TestAlarm", "threshold_rule": {"meter_name":"image", "period":10, "comparison_operator":"eq", "threshold":1.0, "statistic": "avg", "evaluation_periods":10}, "type": "threshold"}' http://localhost:8777/v2/alarms

2.When alarm notifier try to notify with the alarm_action defined, following error occurs.

2014-07-14 16:25:30.721 4429 ERROR ceilometer.alarm.service [-] Action spam for alarm 4d4fba29-2703-4b52-acca-589c9c07856c is unknown, cannot notify

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/107330

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/107330
Committed: https://git.openstack.org/cgit/openstack/ceilometer/commit/?id=3e8f8e988fde82713461740058ba8e12c7d8820f
Submitter: Jenkins
Branch: master

commit 3e8f8e988fde82713461740058ba8e12c7d8820f
Author: Rikimaru Honjo <email address hidden>
Date: Wed Sep 3 21:28:02 2014 +0900

    Add validate alarm_actions schema in alarm API

    Currently, alarm API does not validate schema in alarm_actions.
    When invalid schema is specified, error occurs later in alarm notifier.
    Schema should be validated in advance in API.

    Change-Id: I3b28cfe36c460daead2945ba3577fbc1274f9d91
    Closes-bug: #1342673