Rollup Search API

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This functionality is in technical preview and may be changed or removed in a future release. Elastic will work to fix any issues, but features in technical preview are not subject to the support SLA of official GA features.

The Rollup Search endpoint allows searching rolled-up data using the standard Query DSL. The Rollup Search endpoint is needed because, internally, rolled-up documents utilize a different document structure than the original data. The Rollup Search endpoint rewrites standard Query DSL into a format that matches the rollup documents, then takes the response and rewrites it back to what a client would expect given the original query.

Request

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Rollup Search uses the same SearchRequest that is used by the Search API but it is mostly for aggregations you should set the size to 0 and add aggregations like this:

SearchRequest request = new SearchRequest();
request.source(new SearchSourceBuilder()
    .size(0)
    .aggregation(new MaxAggregationBuilder("max_temperature")
        .field("temperature")));
NOTE
Rollup Search is limited in many ways because only some query elements can be translated into queries against the rollup indices. See the main Rollup Search documentation for more.

Synchronous execution

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

SearchResponse response =
    client.rollup().search(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

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Executing a SearchRequest 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 search method:

client.rollup().searchAsync(request, RequestOptions.DEFAULT, listener); 

The SearchRequest 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 search looks like:

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

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

Called when the execution is successfully completed.

Called when the whole SearchRequest fails.

Response

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Rollup Search returns the same SearchResponse that is used by the Search API and everything can be accessed in exactly the same way. This will access the aggregation built by the example request above:

NumericMetricsAggregation.SingleValue maxTemperature =
        response.getAggregations().get("max_temperature");
assertThat(maxTemperature.value(), closeTo(49.0, .00001));