IMPORTANT: No additional bug fixes or documentation updates will be released for this version. For the latest information, see the current release documentation.

« Index Aliases API Update Indices Settings API »

› › ›

Exists Alias API

edit

IMPORTANT: This documentation is no longer updated. Refer to Elastic's version policy and the latest documentation.

Exists Alias API

edit

Exists Alias Request

edit

The Exists Alias API uses GetAliasesRequest as its request object. One or more aliases can be optionally provided either at construction time or later on through the relevant setter method.

GetAliasesRequest request = new GetAliasesRequest();
GetAliasesRequest requestWithAlias = new GetAliasesRequest("alias1");
GetAliasesRequest requestWithAliases =
        new GetAliasesRequest(new String[]{"alias1", "alias2"});

Optional arguments

edit

The following arguments can optionally be provided:

request.aliases("alias");

One or more aliases to look for

request.indices("index");

The index or indices that the alias is associated with

request.indicesOptions(IndicesOptions.lenientExpandOpen());

Setting IndicesOptions controls how unavailable indices are resolved and how wildcard expressions are expanded

request.local(true);

The local flag (defaults to false) controls whether the aliases need to be looked up in the local cluster state or in the cluster state held by the elected master node

Synchronous Execution

edit

boolean exists = client.indices().existsAlias(request);

Asynchronous Execution

edit

The asynchronous execution of a exists alias request requires both a GetAliasesRequest instance and an ActionListener instance to be passed to the asynchronous method:

client.indices().existsAliasAsync(request, listener);

The GetAliasesRequest 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.

A typical listener for the Boolean response looks like:

ActionListener<Boolean> listener = new ActionListener<Boolean>() {
    @Override
    public void onResponse(Boolean exists) {
        
    }

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

	Called when the execution is successfully completed. The response is provided as an argument
	Called in case of failure. The raised exception is provided as an argument

Exists Alias Response

edit

The Exists Alias API returns a boolean that indicates whether the provided alias (or aliases) was found or not.

« Index Aliases API Update Indices Settings API »