com.yahoo.bard.webservice.web.handlers

Class TopNMapperRequestHandler

java.lang.Object

com.yahoo.bard.webservice.web.handlers.TopNMapperRequestHandler

All Implemented Interfaces:

DataRequestHandler

public class TopNMapperRequestHandler
extends Object
implements DataRequestHandler

Adds the topN result set mapper to allow for top N aggregations based on general group by druid queries. Its priority should be high in the chain of mappers. Currently it's fixed to be right after the partial data mapper. That's why this handler needs to be injected right after PartialDataRequestHandler in the chain of request handlers.

Constructor Summary

Constructors

Constructor and Description
TopNMapperRequestHandler(DataRequestHandler next) Build a topN request handler.

Method Summary

Modifier and Type	Method and Description
boolean	handleRequest(RequestContext context, DataApiRequest request, DruidAggregationQuery<?> druidQuery, ResponseProcessor response) Handle the response, passing the request down the chain as necessary.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

TopNMapperRequestHandler

public TopNMapperRequestHandler(DataRequestHandler next)

Build a topN request handler.

Parameters:

next - The next handler in the chain

Method Detail

handleRequest

public boolean handleRequest(RequestContext context,
                             DataApiRequest request,
                             DruidAggregationQuery<?> druidQuery,
                             ResponseProcessor response)

Description copied from interface: DataRequestHandler

Handle the response, passing the request down the chain as necessary.

Specified by:

handleRequest in interface DataRequestHandler

Parameters:

context - The context for the Request

request - The Api Request Object

druidQuery - The druid query

response - The Async response

Returns:

True if the async response has been processed or passed to a future for processing