Acknowledging a watch enables you to manually throttle
execution of the watch’s actions. An action’s acknowledgement state is stored
in the _status.actions.<id>.ack.state
structure.
To demonstrate let’s create a new watch:
PUT _xpack/watcher/watch/my_watch { "trigger": { "schedule": { "hourly": { "minute": [ 0, 5 ] } } }, "input": { "simple": { "payload": { "send": "yes" } } }, "condition": { "always": {} }, "actions": { "test_index": { "throttle_period": "15m", "index": { "index": "test", "doc_type": "test2" } } } }
The current status of a watch and the state of its actions is returned with the watch definition when you call the Get Watch API:
GET _xpack/watcher/watch/my_watch
The action state of a newly-created watch is awaits_successful_execution
:
{ "found": true, "_id": "my_watch", "_status": { "version": 1, "actions": { "test_index": { "ack": { "timestamp": "2015-05-26T18:04:27.723Z", "state": "awaits_successful_execution" } } }, "state": ... }, "watch": ... }
When the watch executes and the condition matches, the value of the ack.state
changes to ackable
. Let’s force execution of the watch and fetch it again to
check the status:
POST _xpack/watcher/watch/my_watch/_execute GET _xpack/watcher/watch/my_watch
and the action is now in ackable
state:
{ "found": true, "_id": "my_watch", "_status": { "version": 1, "actions": { "test_index": { "ack": { "timestamp": "2015-05-26T18:04:27.723Z", "state": "ackable" } } }, "state": ... }, "watch": ... }
Now we can acknowledge it:
PUT _xpack/watcher/watch/my_watch/_ack/test_index GET _xpack/watcher/watch/my_watch
{ "found": true, "_id": "my_watch", "_status": { "version": 1, "actions": { "test_index": { "ack": { "timestamp": "2015-05-26T18:04:27.723Z", "state": "acknowledged" } } }, "state": ... }, "watch": ... }
Acknowledging an action throttles further executions of that action until its
ack.state
is reset to awaits_successful_execution
. This happens when the
condition of the watch is not met (the condition evaluates to false
).
You can acknowledge multiple actions by assigning the actions
parameter a
comma-separated list of action ids:
POST _xpack/watcher/watch/my_watch/_ack/action1,action2
To acknowledge all of the actions of a watch, simply omit the actions
parameter:
POST _xpack/watcher/watch/my_watch/_ack
Timeouts
If you acknowledge a watch while it is executing, the request blocks and waits
for the watch execution to finish. For some watches, this can take a significant
amount of time. By default, the acknowledge action has a timeout of 10 seconds.
You can change the timeout setting by specifying the master_timeout
parameter.
The following snippet shows how to change the default timeout of the acknowledge action to 30 seconds:
POST _xpack/watcher/watch/my_watch/_ack?master_timeout=30s
Response format
The response format looks like:
{ "_status": { "last_checked": "2015-05-26T18:21:08.630Z", "last_met_condition": "2015-05-26T18:21:08.630Z", "actions": { "my-action": { "ack_status": { "timestamp": "2015-05-26T18:21:09.982Z", "state": "acked" }, "last_execution": { "timestamp": "2015-05-26T18:21:04.106Z", "successful": true }, "last_successful_execution": { "timestamp": "2015-05-26T18:21:04.106Z", "successful": true }, "last_throttle": { "timestamp": "2015-05-26T18:21:08.630Z", "reason": "throttling interval is set to [5 seconds] but time elapsed since last execution is [4 seconds and 530 milliseconds]" } } } } }