Stop transform API

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Stops a started transform. It accepts a StopTransformRequest object and responds with a StopTransformResponse object.

Stop transform request

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A StopTransformRequest object requires a non-null id. id can be a comma separated list of IDs or a single ID. Wildcards, * and _all are also accepted.

StopTransformRequest request =
        new StopTransformRequest("mega-transform"); 

Constructing a new stop request referencing an existing transform.

Optional arguments

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The following arguments are optional.

request.setWaitForCompletion(Boolean.TRUE);  
request.setTimeout(TimeValue.timeValueSeconds(30));  
request.setAllowNoMatch(true); 

If true wait for the transform task to stop before responding.

Controls the amount of time to wait until the transform stops.

Whether to ignore if a wildcard expression matches no transforms.

Synchronous execution

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

StopTransformResponse response =
        client.transform().stopTransform(
                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 StopTransformRequest 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 stop-transform method:

client.transform().stopTransformAsync(
        request, RequestOptions.DEFAULT, listener); 

The StopTransformRequest 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 stop-transform looks like:

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

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

Called when the execution is successfully completed.

Called when the whole StopTransformRequest fails.

Response

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The returned StopTransformResponse object acknowledges the transform has stopped.