Rollover Index API

Rollover Request

The Rollover Index API requires a RolloverRequest instance. A RolloverRequest requires two string arguments at construction time, and one or more conditions that determine when the index has to be rolled over:

RolloverRequest request = new RolloverRequest("alias", "index-2"); 
request.addMaxIndexAgeCondition(new TimeValue(7, TimeUnit.DAYS)); 
request.addMaxIndexDocsCondition(1000); 
request.addMaxIndexSizeCondition(new ByteSizeValue(5, ByteSizeUnit.GB)); 

The alias (first argument) that points to the index to rollover, and the name of the new index in case the rollover operation is performed. The new index argument is optional, and can be set to null

Condition on the age of the index

Condition on the number of documents in the index

Condition on the size of the index

Optional arguments

The following arguments can optionally be provided:

request.dryRun(true); 

Whether the rollover should be performed (default) or only simulated

request.setTimeout(TimeValue.timeValueMinutes(2)); 

Timeout to wait for the all the nodes to acknowledge the index is opened as a TimeValue

request.setMasterTimeout(TimeValue.timeValueMinutes(1)); 

Timeout to connect to the master node as a TimeValue

request.getCreateIndexRequest().waitForActiveShards(ActiveShardCount.from(2)); 
request.getCreateIndexRequest().waitForActiveShards(ActiveShardCount.DEFAULT); 

Sets the number of active shard copies to wait for before the rollover index API returns a response

Resets the number of active shard copies to wait for to the default value

request.getCreateIndexRequest().settings(Settings.builder()
        .put("index.number_of_shards", 4)); 

Add the settings to apply to the new index, which include the number of shards to create for it

String mappings = "{\"properties\":{\"field-1\":{\"type\":\"keyword\"}}}";
request.getCreateIndexRequest().mapping(mappings, XContentType.JSON); 

Add the mappings to associate the new index with. See Index mappings for examples on the different ways to provide mappings

request.getCreateIndexRequest().alias(new Alias("another_alias")); 

Add the aliases to associate the new index with

Synchronous Execution

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

RolloverResponse rolloverResponse = client.indices().rollover(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

Executing a RolloverRequest 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 rollover-index method:

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

The RolloverRequest 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 rollover-index looks like:

ActionListener<RolloverResponse> listener = new ActionListener<RolloverResponse>() {
    @Override
    public void onResponse(RolloverResponse rolloverResponse) {
        
    }

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

Called when the execution is successfully completed.

Called when the whole RolloverRequest fails.

Rollover Response

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

boolean acknowledged = rolloverResponse.isAcknowledged(); 
boolean shardsAcked = rolloverResponse.isShardsAcknowledged(); 
String oldIndex = rolloverResponse.getOldIndex(); 
String newIndex = rolloverResponse.getNewIndex(); 
boolean isRolledOver = rolloverResponse.isRolledOver(); 
boolean isDryRun = rolloverResponse.isDryRun(); 
Map<String, Boolean> conditionStatus = rolloverResponse.getConditionStatus();

Indicates whether all of the nodes have acknowledged the request

Indicates whether the requisite number of shard copies were started for each shard in the index before timing out

The name of the old index, eventually rolled over

The name of the new index

Whether the index has been rolled over

Whether the operation was performed or it was a dry run

The different conditions and whether they were matched or not