使用Elasticsearch聚合搜索進行數據的分類統計

HTTP請求

• 單個條件聚合，根據某一個維度去聚合統計

GET /zwfw/_search
{
  "size": 0, 
 "aggregations" : {
    "organDn.keyword_arr" : {
      "terms" : {
        "field" : "organDn.keyword",
        "size" : 100,
        "min_doc_count" : 1,
        "shard_min_doc_count" : 0,
        "show_term_doc_count_error" : false,
        "order" : [
          {
            "_count" : "desc"
          },
          {
            "_term" : "asc"
          }
        ]
      }
    }
  }
}

• 子聚合，先根據某一個維度聚合，再在這個維度裏，根據另一個維度聚合

GET /zwfw/_search
{
  "size" : 0,
  "aggregations" : {
    "platformCode.keyword_arr" : {
      "terms" : {
        "field" : "platformCode.keyword",
        "size" : 20,
        "min_doc_count" : 1,
        "shard_min_doc_count" : 0,
        "show_term_doc_count_error" : false,
        "order" : [
          {
            "_count" : "desc"
          },
          {
            "_term" : "asc"
          }
        ]
      },
      "aggregations" : {
        "siteId_arr" : {
          "terms" : {
            "field" : "siteId",
            "size" : 100,
            "min_doc_count" : 1,
            "shard_min_doc_count" : 0,
            "show_term_doc_count_error" : false,
            "order" : [
              {
                "_count" : "desc"
              },
              {
                "_term" : "asc"
              }
            ]
          }
        }
      }
    }
  }
}

java連接客戶端請求

 @Override
    public Map<String, Object> aggregateByField(EsQueryVO queryVO) {
        Map<String, Object> result = new HashedMap();

        SearchRequestBuilder builder = esQueryBuild(queryVO);
        TermsAggregationBuilder aggregation = AggregationBuilders.terms(queryVO.getAggregateKey()+"_arr")
                .field(queryVO.getAggregateKey());
        if(queryVO.getAggregateOrder() != null){
            aggregation.order(Terms.Order.count(queryVO.getAggregateOrder()));
        }
        if(null != queryVO.getAggregateSize()){
            aggregation.size(queryVO.getAggregateSize());
        }else {
            aggregation.size(2000);
        }
        builder = builder.addAggregation(aggregation).setSize(0);
        logger.info("builder:\n{}",builder);
        SearchResponse response = builder.get();
        if(response != null){
            String bucketKey = queryVO.getAggregateKey()+"_arr";
            Terms terms = response.getAggregations().get(bucketKey);
            Map<String,Long> staticMap = new LinkedHashMap();
            for (Terms.Bucket entry1 : terms.getBuckets()) {
                String key = entry1.getKey().toString();          // bucket key
                Long docCount = entry1.getDocCount();            // Doc count
                staticMap.put(key,docCount);
            }
            result.put(bucketKey,staticMap);
        }

        return result;
    }

    @Override
    public Map<String, Long> aggregateByField(EsQueryVO queryVO, String subField) {
        Map<String, Long> result = new HashedMap();

        //如果包含子查詢
        if(!StringUtils.isEmpty(subField)){
            SearchRequestBuilder builder = esQueryBuild(queryVO);
            TermsAggregationBuilder aggregation = AggregationBuilders.terms(queryVO.getAggregateKey()+"_arr")
                    .field(queryVO.getAggregateKey()).size(20);
            aggregation = aggregation.subAggregation(
                    AggregationBuilders.terms(subField+"_arr").field(subField).size(2000));
            if(queryVO.getAggregateOrder() != null){
                aggregation.order(Terms.Order.count(queryVO.getAggregateOrder()));
            }
            if(null != queryVO.getAggregateSize()){
                aggregation.size(queryVO.getAggregateSize());
            }else {
                aggregation.size(2000);
            }
            builder = builder.addAggregation(aggregation).setSize(0);
            logger.info("builder:\n{}",builder);
            SearchResponse response = builder.get();
            if(response != null){
                String bucketKey = queryVO.getAggregateKey()+"_arr";
                Terms terms = response.getAggregations().get(bucketKey);
                for (Terms.Bucket entry1 : terms.getBuckets()) {
                    String key = entry1.getKey().toString();          // bucket key
                    Aggregations subAgg = entry1.getAggregations();
                    if(subAgg.asList().size() > 0){
                        Terms terms2 = subAgg.get(subField+"_arr");
                        for (Terms.Bucket entry2 : terms2.getBuckets()) {
                            String key2 = entry2.getKey().toString();          // bucket key
                            Long docCount2 = entry2.getDocCount();            // Doc count
                            result.put(key + "_" + key2,docCount2);
                        }
                    }
                }
            }

            return result;
        }else {
            Map<String, Object> aggs = aggregateByField(queryVO);
            if(aggs != null && aggs.size() > 0){
                return (Map<String, Long>)aggs.get(queryVO.getAggregateKey()+"_arr");
            }
            return null;
        }
    }

• 核心是構造需要聚合的維度對象TermsAggregationBuilder，然後再使用addAggregation加到搜索後

TermsAggregationBuilder aggregation = AggregationBuilders.terms(searchQueryVO.getAggregateKey()+"_arr")
                .field(searchQueryVO.getAggregateKey());
aggregation.size(2000);

• 得到的結果需要處理下，才方便使用。

			Terms terms = response.getAggregations().get(bucketKey);
            Map<String,Long> staticMap = new LinkedHashMap();
            for (Terms.Bucket entry1 : terms.getBuckets()) {
                String key = entry1.getKey().toString();          // bucket key
                Long docCount = entry1.getDocCount();            // Doc count
                staticMap.put(key,docCount);
                logger.info("[{}]key [{}], doc_count [{}]",bucketKey, key, docCount);
            }
            result.put(bucketKey,staticMap);