Put Watch API

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The PUT watch API either registers a new watch in Watcher or update an existing one. Once registered, a new document will be added to the .watches index, representing the watch, and its trigger will immediately be registered with the relevant trigger engine (typically the scheduler, for the schedule trigger).

Putting a watch must be done via this API only. Do not put a watch directly to the .watches index using Elasticsearch’s Index API. If X-Pack security is enabled, make sure no write privileges are granted to anyone over the .watches index.

The following example adds a watch with the my-watch id that has the following characteristics:

  • The watch schedule triggers every minute.
  • The watch search input looks for any 404 HTTP responses that occurred in the last five minutes.
  • The watch condition checks if any search hits where found.
  • When found, the watch action sends an email to an administrator.
PUT _xpack/watcher/watch/my-watch
{
  "trigger" : {
    "schedule" : { "cron" : "0 0/1 * * * ?" }
  },
  "input" : {
    "search" : {
      "request" : {
        "indices" : [
          "logstash*"
        ],
        "body" : {
          "query" : {
            "bool" : {
              "must" : {
                "match": {
                   "response": 404
                }
              },
              "filter" : {
                "range": {
                  "@timestamp": {
                    "from": "{{ctx.trigger.scheduled_time}}||-5m",
                    "to": "{{ctx.trigger.triggered_time}}"
                  }
                }
              }
            }
          }
        }
      }
    }
  },
  "condition" : {
    "compare" : { "ctx.payload.hits.total" : { "gt" : 0 }}
  },
  "actions" : {
    "email_admin" : {
      "email" : {
        "to" : "admin@domain.host.com",
        "subject" : "404 recently encountered"
      }
    }
  }
}

A watch has the following fields:

Name Description

trigger

The trigger that defines when the watch should run.

input

The input that defines the input that loads the data for the watch.

condition

The condition that defines if the actions should be run.

actions

The list of actions that will be run if the condition matches

metadata

Metadata json that will be copied into the history entries.

throttle_period

The minimum time between actions being run, the default for this is 5 seconds. This default can be changed in the config file with the setting xpack.watcher.throttle.period.default_period.

Timeouts

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When updating a watch while it is executing, the put action will block and wait for the watch execution to finish. Depending on the nature of the watch, in some situations this can take a while. For this reason, the put watch action is associated with a timeout that is set to 10 seconds by default. You can control this timeout by passing in the master_timeout parameter.

The following snippet shows how to change the default timeout of the put action to 30 seconds:

PUT _xpack/watcher/watch/my-watch?master_timeout=30s

Controlling Default Active State

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When adding a watch you can also define its initial active state. You do that by setting the active parameter. The following command add a watch and sets it to be inactive by default:

PUT _xpack/watcher/watch/my-watch?active=false

If you omit the active parameter, the watch is active by default.