Stats API

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The stats API returns the current Watcher metrics. You can control what metrics this API returns using the metric parameter.

The supported metrics are:

Metric Description

executing_watches

Include the current executing watches in the response.

queued_watches

Include the watches queued for execution in the response.

_all

Include all metrics in the response.

The Watcher stats API always returns basic metrics regardless of the metric option. The following example calls the stats API including the basic metrics:

GET _xpack/watcher/stats

A successful call returns a JSON structure similar to the following example:

{
   "watcher_state": "started",  
   "watch_count": 1, 
   "execution_thread_pool": {
      "size": 1000, 
      "max_size": 1 
   }
}

The current state of watcher. May be either started, starting or stopped.

The number of watches currently registered.

The number of watches that were triggered and currently queued for execution.

The largest size of the execution thread pool indicating the largest number of concurrent executing watches.

Current executing watches metric

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The current executing watches metric gives insight into the watches that are currently being executed by Watcher. Additional information is shared per watch that is currently executing. This information includes the watch_id, the time its execution started and its current execution phase.

To include this metric, the metric option should be set to executing_watches or _all.

The following example specifies the metric option as a query string argument and will include the basic metrics and metrics about the current executing watches:

GET _xpack/watcher/stats?metric=executing_watches

The following example specifies the metric option as part of the url path:

GET _xpack/watcher/stats/current_watches

The following snippet shows an example of a successful JSON response that captures a watch in execution:

{
   "watcher_state": "started",
   "watch_count": 2,
   "execution_thread_pool": {
      "queue_size": 1000,
      "max_size": 20
   },
   "current_watches": [ 
      {
         "watch_id": "slow_condition", 
         "watch_record_id": "slow_condition_3-2015-05-13T07:42:32.179Z", 
         "triggered_time": "2015-05-12T11:53:51.800Z", 
         "execution_time": "2015-05-13T07:42:32.179Z", 
         "execution_phase": "condition" 
      }
   ]
}

A list of all the Watches that are currently being executed by Watcher. When no watches are currently executing an empty array is returned. The captured watches are sorted by execution time in descending order. Thus the longest running watch is always at the top.

The id of the watch being executed.

The id of the watch record.

The time the watch was triggered by the trigger engine.

The time the watch was executed. This is just before the input is being executed.

The current watch execution phase. Can be input, condition actions, awaits_execution, started, watch_transform, aborted, finished.

In addition you can also specify the emit_stacktraces=true parameter, which adds stack traces for each watch that is being executed. These stacktraces can give you more insight into an execution of a watch.

Queued watches metric

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Watcher moderates the execution of watches such that their execution won’t put too much pressure on the node and its resources. If too many watches trigger concurrently and there isn’t enough capacity to execute them all, some of the watches are queued, waiting for the current executing watches to finish their execution. The queued watches metric gives insight on these queued watches.

To include this metric, the metric option should include queued_watches or _all.

The following example specifies the queued_watches metric option and includes both the basic metrics and the queued watches:

GET _xpack/watcher/stats/queued_watches

An example of a successful JSON response that captures a watch in execution:

{
   "watcher_state": "started",
   "watch_count": 10,
   "execution_thread_pool": {
      "queue_size": 1000,
      "max_size": 20
   },
   "queued_watches": [ 
         {
            "watch_id": "slow_condition4", 
            "watch_record_id": "slow_condition4_223-2015-05-21T11:59:59.811Z", 
            "triggered_time": "2015-05-21T11:59:59.811Z", 
            "execution_time": "2015-05-21T11:59:59.811Z" 
         },
      ...
   ]
}

A list of all watches that are currently queued for execution. When no watches are queued, an empty array is returned.

The id of the watch queued for execution.

The id of the watch record.

The time the watch was triggered by the trigger engine.

The time the watch was went into a queued state.