ES中的收集器

ES中的收集器

org.elasticsearch.search.query.QueryPhase#executeInternal 

            final linkedList collectors = new linkedList<>();
            // whether the chain contains a collector that filters documents
            boolean hasFilterCollector = false;
            if (searchContext.terminateAfter() != SearchContext.DEFAULT_TERMINATE_AFTER) {
                // add terminate_after before the filter collectors
                // it will only be applied on documents accepted by these filter collectors
                collectors.add(createEarlyTerminationCollectorContext(searchContext.terminateAfter()));
                // this collector can filter documents during the collection
                hasFilterCollector = true;
            }
            if (searchContext.parsedPostFilter() != null) {
                // add post filters before aggregations
                // it will only be applied to top hits
                collectors.add(createFilteredCollectorContext(searcher, searchContext.parsedPostFilter().query()));
                // this collector can filter documents during the collection
                hasFilterCollector = true;
            }
            if (searchContext.queryCollectors().isEmpty() == false) {
                // plug in additional collectors, like aggregations
                collectors.add(createMultiCollectorContext(searchContext.queryCollectors().values()));
            }
            if (searchContext.minimumScore() != null) {
                // apply the minimum score after multi collector so we filter aggs as well
                collectors.add(createMinScoreCollectorContext(searchContext.minimumScore()));
                // this collector can filter documents during the collection
                hasFilterCollector = true;
            }

org.elasticsearch.search.query.QueryPhase#searchWithCollector 

        // create the top docs collector last when the other collectors are known
        final TopDocsCollectorContext topDocsFactory = createTopDocsCollectorContext(searchContext, hasFilterCollector);
        // add the top docs collector, the first collector context in the chain
        collectors.addFirst(topDocsFactory);

{
  "min_score": 10,
  "query": {
    "bool": {
      "must": [
        {
          "term": {
            "speaker": "HOTSPUR"
          }
        }
      ]
    }
  },
  "post_filter": {
    "term": {
      "speaker": "HOTSPUR"
    }
  },
  "aggs": {
    "all_colors": {
      "terms": {
        "field": "speaker",
        "size": 200
      }
    }
  }
}

    
    static Collector createQueryCollector(List collectors) throws IOException {
        Collector collector = null;
        for (QueryCollectorContext ctx : collectors) {
            collector = ctx.create(collector);
        }
        return collector;
    }

 转换后的tree结构