Engine.Searcher engineSearcher = indexShard.searcher();
SearchContext context = new SearchContext(idGenerator.incrementAndGet(), shardTarget, request.searchType(), request.numberOfShards(), request.timeout(), request.types(), engineSearcher, indexService, scriptService);
SearchContext.setCurrent(context);
try {
context.scroll(request.scroll());
parseSource(context, request.source(), request.sourceOffset(), request.sourceLength());
parseSource(context, request.extraSource(), request.extraSourceOffset(), request.extraSourceLength());
// if the from and size are still not set, default them