Ack Watch API

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Execution

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Acknowledging a watch enables you to manually throttle execution of a watch’s actions. A watch can be acknowledged through the following request:

AckWatchRequest request = new AckWatchRequest("my_watch_id", 
    "logme", "emailme"); 

The ID of the watch to ack.

An optional list of IDs representing the watch actions that should be acked. If no action IDs are provided, then all of the watch’s actions will be acked.

Response

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The returned AckWatchResponse contains the new status of the requested watch:

WatchStatus watchStatus = response.getStatus();
ActionStatus actionStatus = watchStatus.actionStatus("logme"); 
AckStatus.State ackState = actionStatus.ackStatus().state(); 

The status of a specific action that was acked.

The acknowledgement state of the action. If the action was successfully acked, this state will be equal to AckStatus.State.ACKED.

Synchronous execution

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When executing a AckWatchRequest in the following manner, the client waits for the AckWatchResponse to be returned before continuing with code execution:

AckWatchResponse response = client.watcher().ackWatch(request, RequestOptions.DEFAULT);

Synchronous calls may throw an IOException in case of either failing to parse the REST response in the high-level REST client, the request times out or similar cases where there is no response coming back from the server.

In cases where the server returns a 4xx or 5xx error code, the high-level client tries to parse the response body error details instead and then throws a generic ElasticsearchException and adds the original ResponseException as a suppressed exception to it.

Asynchronous execution

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Executing a AckWatchRequest can also be done in an asynchronous fashion so that the client can return directly. Users need to specify how the response or potential failures will be handled by passing the request and a listener to the asynchronous ack-watch method:

client.watcher().ackWatchAsync(request, RequestOptions.DEFAULT, listener); 

The AckWatchRequest to execute and the ActionListener to use when the execution completes

The asynchronous method does not block and returns immediately. Once it is completed the ActionListener is called back using the onResponse method if the execution successfully completed or using the onFailure method if it failed. Failure scenarios and expected exceptions are the same as in the synchronous execution case.

A typical listener for ack-watch looks like:

ActionListener<AckWatchResponse> listener = new ActionListener<AckWatchResponse>() {
    @Override
    public void onResponse(AckWatchResponse response) {
        
    }

    @Override
    public void onFailure(Exception e) {
        
    }
};

Called when the execution is successfully completed.

Called when the whole AckWatchRequest fails.