Get Rollup Capabilities API

The Get Rollup Capabilities API allows the user to query a target index pattern (logstash-*, etc) and determine if there are any rollup jobs that are/were configured to rollup that pattern. The API accepts a GetRollupCapsRequest object as a request and returns a GetRollupCapsResponse.

Get Rollup Capabilities Request

A GetRollupCapsRequest requires a single parameter: the target index or index pattern (e.g. logstash-*):

GetRollupCapsRequest getRollupCapsRequest = new GetRollupCapsRequest("docs");

Execution

The Get Rollup Capabilities API can be executed through a RollupClient instance. Such instance can be retrieved from a RestHighLevelClient using the rollup() method:

GetRollupCapsResponse capsResponse = client.rollup().getRollupCapabilities(getRollupCapsRequest, RequestOptions.DEFAULT);

Response

The returned GetRollupCapsResponse holds lists and maps of values which correspond to the capabilities of the target index/index pattern (what jobs were configured for the pattern, where the data is stored, what aggregations are available, etc). It provides essentially the same data as the original job configuration, just presented in a different manner.

For example, if we had created a job with the following config:

final String indexPattern = "docs";
final String rollupIndexName = "rollup";
final String cron = "*/1 * * * * ?";
final int pageSize = 100;
final TimeValue timeout = null;

String id = "job_1";
RollupJobConfig config = new RollupJobConfig(id, indexPattern, rollupIndexName, cron,
    pageSize, groups, metrics, timeout);

PutRollupJobRequest request = new PutRollupJobRequest(config);
AcknowledgedResponse response = client.rollup().putRollupJob(request, RequestOptions.DEFAULT);

boolean acknowledged = response.isAcknowledged();

The GetRollupCapsResponse object would contain the same information, laid out in a slightly different manner:

Map<String, RollableIndexCaps> rolledPatterns = capsResponse.getJobs();

RollableIndexCaps docsPattern = rolledPatterns.get("docs");

// indexName will be "docs" in this case... the index pattern that we rolled up
String indexName = docsPattern.getIndexName();

// Each index pattern can have multiple jobs that rolled it up, so getJobCaps()
// returns a list of jobs that rolled up the pattern
List<RollupJobCaps> rollupJobs = docsPattern.getJobCaps();
RollupJobCaps jobCaps = rollupJobs.get(0);

// jobID is the identifier we used when we created the job (e.g. job1)
String jobID = jobCaps.getJobID();

// rollupIndex is the location that the job stored it's rollup docs (e.g. rollup)
String rollupIndex = jobCaps.getRollupIndex();

// indexPattern is the same as the indexName that we retrieved earlier, redundant info
assert jobCaps.getIndexPattern().equals(indexName);

// Finally, fieldCaps are the capabilities of individual fields in the config
// The key is the field name, and the value is a RollupFieldCaps object which
// provides more info.
Map<String, RollupJobCaps.RollupFieldCaps> fieldCaps = jobCaps.getFieldCaps();

// If we retrieve the "timestamp" field, it returns a list of maps.  Each list
// item represents a different aggregation that can be run against the "timestamp"
// field, and any additional details specific to that agg (interval, etc)
List<Map<String, Object>> timestampCaps = fieldCaps.get("timestamp").getAggs();
assert timestampCaps.get(0).toString().equals("{agg=date_histogram, delay=7d, interval=1h, time_zone=UTC}");

// In contrast to the timestamp field, the temperature field has multiple aggs configured
List<Map<String, Object>> temperatureCaps = fieldCaps.get("temperature").getAggs();
assert temperatureCaps.toString().equals("[{agg=min}, {agg=max}, {agg=sum}]");

Asynchronous Execution

This request can be executed asynchronously:

client.rollup().getRollupCapabilitiesAsync(getRollupCapsRequest, RequestOptions.DEFAULT, listener); 

The GetRollupCapsRequest 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 GetRollupCapsResponse looks like:

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

        
    }

    @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