Put Auto Follow Pattern APIedit

Requestedit

The Put Auto Follow Pattern API allows you to store auto follow patterns in order to automatically follow leader indices in a remote clusters matching certain index name patterns.

PutAutoFollowPatternRequest request =
    new PutAutoFollowPatternRequest(
        "my_pattern", 
        "local", 
        Arrays.asList("logs-*", "metrics-*"), 
        Arrays.asList("logs-excluded", "metrics-excluded") 
);
request.setFollowIndexNamePattern("copy-{{leader_index}}"); 
Settings settings =
    Settings.builder().put("index.number_of_replicas", 0L).build();
request.setSettings(settings); 

The name of the auto follow pattern.

The name of the remote cluster.

The leader index patterns.

The leader index exclusion patterns.

The pattern used to create the follower index.

The settings overrides for the follower index.

Responseedit

The returned AcknowledgedResponse indicates if the put auto follow pattern request was received.

boolean acknowledged = response.isAcknowledged(); 

Whether or not the put auto follow pattern request was acknowledged.

Synchronous executionedit

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

AcknowledgedResponse response = client.ccr()
    .putAutoFollowPattern(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 executionedit

Executing a PutAutoFollowPatternRequest 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 ccr-put-auto-follow-pattern method:

client.ccr().putAutoFollowPatternAsync(request,
    RequestOptions.DEFAULT, listener); 

The PutAutoFollowPatternRequest 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 ccr-put-auto-follow-pattern looks like:

ActionListener<AcknowledgedResponse> listener =
    new ActionListener<AcknowledgedResponse>() {
        @Override
        public void onResponse(AcknowledgedResponse response) { 
            boolean acknowledged = response.isAcknowledged();
        }

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

Called when the execution is successfully completed.

Called when the whole PutAutoFollowPatternRequest fails.