Index Aliases APIedit

Indices Aliases Requestedit

The Index Aliases API allows aliasing an index with a name, with all APIs automatically converting the alias name to the actual index name.

An IndicesAliasesRequest must have at least one AliasActions:

IndicesAliasesRequest request = new IndicesAliasesRequest(); 
AliasActions aliasAction =
        new AliasActions(AliasActions.Type.ADD)
        .index("index1")
        .alias("alias1"); 
request.addAliasAction(aliasAction); 

Creates an IndicesAliasesRequest

Creates an AliasActions that aliases index test1 with alias1

Adds the alias action to the request

The following action types are supported: add - alias an index, remove - removes the alias associated with the index, and remove_index - deletes the index.

AliasActions addIndexAction =
        new AliasActions(AliasActions.Type.ADD)
        .index("index1")
        .alias("alias1")
        .filter("{\"term\":{\"year\":2016}}"); 
AliasActions addIndicesAction =
        new AliasActions(AliasActions.Type.ADD)
        .indices("index1", "index2")
        .alias("alias2")
        .routing("1"); 
AliasActions removeAction =
        new AliasActions(AliasActions.Type.REMOVE)
        .index("index3")
        .alias("alias3"); 
AliasActions removeIndexAction =
        new AliasActions(AliasActions.Type.REMOVE_INDEX)
        .index("index4"); 

Creates an alias alias1 with an optional filter on field year

Creates an alias alias2 associated with two indices and with an optional routing

Removes the associated alias alias3

remove_index is just like Delete Index API

Optional argumentsedit

The following arguments can optionally be provided:

request.timeout(TimeValue.timeValueMinutes(2)); 
request.timeout("2m"); 

Timeout to wait for the all the nodes to acknowledge the operation as a TimeValue

Timeout to wait for the all the nodes to acknowledge the operation as a String

request.masterNodeTimeout(TimeValue.timeValueMinutes(1)); 
request.masterNodeTimeout("1m"); 

Timeout to connect to the master node as a TimeValue

Timeout to connect to the master node as a String

Synchronous Executionedit

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

AcknowledgedResponse indicesAliasesResponse =
        client.indices().updateAliases(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 IndicesAliasesRequest 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 update-aliases method:

client.indices().updateAliasesAsync(request, RequestOptions.DEFAULT, listener); 

The IndicesAliasesRequest 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 update-aliases looks like:

ActionListener<AcknowledgedResponse> listener =
        new ActionListener<AcknowledgedResponse>() {
    @Override
    public void onResponse(AcknowledgedResponse indicesAliasesResponse) {
        
    }

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

Called when the execution is successfully completed.

Called when the whole IndicesAliasesRequest fails.

Indices Aliases Responseedit

The returned IndicesAliasesResponse allows to retrieve information about the executed operation as follows:

boolean acknowledged = indicesAliasesResponse.isAcknowledged(); 

Indicates whether all of the nodes have acknowledged the request