ElasticSearch7.4.2：RestHighLevelClient应用

ElasticSearch7.4.2：RestHighLevelClient

这次项目应客户要求使用7.4.2 highLevel-client版本，由于之前做的es搜索还是使用SpringData+Transport来操作,所以这次也是看了好久的官方api以及好多大神的笔记，但是由于是版本太高，使用的人可能或许太少或许大神是没时间写笔记记录，所以做的过程中也遇到了好多的问题和踩了好多的坑，所以现在记录一下自己做的过程，一方面希望能给大家提供一些帮助，一方面也算是对这方面的回顾，也希望能有大神提供一些建议和批评，互相讨论，共同进步。

一：pom依赖

<dependency>
    <groupId>org.elasticsearch.client</groupId>
    <artifactId>elasticsearch-rest-high-level-client</artifactId>
    <version>7.4.0</version>
</dependency>

<dependency>
    <groupId>org.elasticsearch</groupId>
    <artifactId>elasticsearch</artifactId>
    <version>7.4.0</version>
</dependency>
<!-- https://mvnrepository.com/artifact/commons-logging/commons-logging -->
<dependency>
    <groupId>commons-logging</groupId>
    <artifactId>commons-logging</artifactId>
    <version>1.2</version>
</dependency>

<!-- https://mvnrepository.com/artifact/commons-codec/commons-codec -->
<dependency>
    <groupId>commons-codec</groupId>
    <artifactId>commons-codec</artifactId>
    <version>1.13</version>
</dependency>

<!-- https://mvnrepository.com/artifact/org.apache.httpcomponents/httpcore -->
<dependency>
    <groupId>org.apache.httpcomponents</groupId>
    <artifactId>httpcore</artifactId>
    <version>4.4.12</version>
</dependency>

<!-- https://mvnrepository.com/artifact/org.apache.httpcomponents/httpclient -->
<dependency>
    <groupId>org.apache.httpcomponents</groupId>
    <artifactId>httpclient</artifactId>
    <version>4.5.10</version>
</dependency>

二：后台创建index，mapping和同步数据

一：controller层

@RestController
public class EsController {

    @Autowired
    EsSearchService esSearchService;
    @PostMapping("checkIndex")
    //检查该index是否存在
    public boolean checkIndex(String index){
        return esSearchService.checkIndex(index);
    }
    @PostMapping("createIndex")
    //创建index，可以自己手动输入创建，也可以写在代码中，我是直接写在代码中里，一方面是懒，也方便管理
    public String createIndex(){
        return esSearchService.createIndex();
    }

    @PostMapping("createMapping")
    //创建mapping，可以用dts也可以自己写，我是自己用API写的，API创建的需要注意数据类型
    public String createMapping(){
        return esSearchService.createMapping();
    }

    @PostMapping("saveById")
    //通过id新增
    public int synchroEsDatas(@RequestBody List<EsSearchDTO> es){
        return esSearchService.synchroEsDatas(es);
    }

    @PostMapping("saveAll")
    //批量新增
    public int save(){
        return esSearchService.synchroEsDatasAll();
    }

二：实现类

public class EsSearchServiceImp implements EsSearchService{

   
//如果是用的阿里云的Es服务器，可以在这里注入
    @Value("${aliyun.es.username}")
    private String username;
    @Value("${aliyun.es.password}")
    private String password;
    @Value("${aliyun.es.hostname}")
    private String hostname;
    @Value("${aliyun.es.port}")
    private int port;
    @Value("${aliyun.es.protocol}")
    private String protocol;

    //获取es连接（不需要密码可以直接连接）
    //private RestHighLevelClient restHighLevelClient = new RestHighLevelClient(RestClient
    // .builder(new HttpHost(hostname, port, protocol)));
    //使用密码连接（阿里云给的API）
    public  RestHighLevelClient getRestClient(){
        CredentialsProvider credentialsProvider = new BasicCredentialsProvider();
        credentialsProvider.setCredentials(AuthScope.ANY,new UsernamePasswordCredentials(username, password));
        RestClientBuilder builder = RestClient.builder(new HttpHost(hostname, port, protocol))
                .setHttpClientConfigCallback(new RestClientBuilder.HttpClientConfigCallback() {
                    @Override
                    public HttpAsyncClientBuilder customizeHttpClient(HttpAsyncClientBuilder httpAsyncClientBuilder) {
                        return httpAsyncClientBuilder.setDefaultCredentialsProvider(credentialsProvider);
                    }
                }).setRequestConfigCallback(new RestClientBuilder.RequestConfigCallback() {
                    @Override
                    public RequestConfig.Builder customizeRequestConfig(RequestConfig.Builder requestBuilder) {
                        requestBuilder.setConnectTimeout(5000);
                        requestBuilder.setSocketTimeout(40000);
                        requestBuilder.setConnectionRequestTimeout(1000);
                        return requestBuilder;
                    }
                });
        RestHighLevelClient restHighLevelClient = new RestHighLevelClient(builder);
        return restHighLevelClient;
    }

    @Resource
    private EsSearchMapper esSearchMapper;

   
//    @Async("taskExecutor") 加线程池自动同步
//异步同步所有数据
    @Override
    public Integer synchroEsDatasAll(){
        int syncount = 0;
        try {
                //异步执行延迟5秒
                Thread.sleep(5000);
                //获取需要同步的记录
                List<EsSearchEntity> list = esSearchMapper.selectESObject(null);
                if(list != null && list.size() >0 && !list.isEmpty()){
                    log.info("ES同步开始");
                    //同步ES
                    syncount = this.saveDocumentByIndex(list);
                    log.info("ES同步完成");
                } else {
                    log.info("未获取到ES同步记录集");
                }
        } catch (Exception e){
            e.printStackTrace();
            log.error("ES同步数据异常");
        }
        return syncount;
    }

   //删除数据
    public void deleteUtil(String id) throws IOException {
       Map<String,Object> _Map=new HashMap<String,Object>();
        _Map.put("id", id);
       DeleteByQueryRequest deleteByQueryRequest = new DeleteByQueryRequest(IndexData.indexName);
       BoolQueryBuilder boolQueryBuilder = QueryBuilders.boolQuery();
       for (Map.Entry<String,Object> id:_Map.entrySet()){
            boolQueryBuilder.must(QueryBuilders.termQuery(id.getKey(),id.getValue()));
       }
       deleteByQueryRequest.setQuery(boolQueryBuilder);
       BulkByScrollResponse bulkByScrollResponse = getRestClient().deleteByQuery(deleteByQueryRequest,RequestOptions.DEFAULT);
       bulkByScrollResponse.getDeleted();
    }


    @Override
    //判断index是否存在
    public  boolean checkIndex(String index) {

        try {
            GetIndexRequest request = new GetIndexRequest(index);
            boolean result = getRestClient().indices().exists(request, RequestOptions.DEFAULT);
            return result;
        } catch (IOException e) {
            e.printStackTrace();
            return false;
        }
    }

    @Override
    //创建index
    public String createIndex() {

        String result = "创建成功";
        CreateIndexRequest createIndexRequest = new CreateIndexRequest(IndexData.indexName);
        try {
            CreateIndexResponse createIndexResponse = getRestClient().indices().create(createIndexRequest,RequestOptions.DEFAULT);

            if (!createIndexResponse.isAcknowledged()){
                result = "创建失败";
            }else{
                result = "索引已经存在";
            }
        } catch (IOException e) {
            e.printStackTrace();
            result = "接口异常";
        }
        return result;
    }

    @Override
    //创建mapping
    //注意数据格式，此版本已经取去除String格式，改为text和keyword格式，其中text格式支持分词和建立索引，支持模糊查询和精确查询，不支持聚合，keyword不支持分词，支持模糊查询和精确查询，支持聚合查询，排序
    public String createMapping() {
        String result = "mapping创建成功";
        PutMappingRequest putMappingRequest = new PutMappingRequest(IndexData.indexName);

        XContentBuilder builder = null;
        try {
            builder = XContentFactory.jsonBuilder()
                    .startObject()
                    .startObject("properties")
                    .startObject("id")
                    .field("type","keyword")
                    .field("index",true)
                    .endObject()
                    .startObject("pics")
                    .field("type","text")
                    .field("index",false)
                    .endObject()
                    .startObject("name")
                    .field("type","text")
                    .field("index",true)
                    //分词器采用ik_smart分词器
                    .field("analyzer","ik_smart")
                    .endObject()
                    .startObject("prices")
                    .field("type","double")
                    .field("index",true)
                    .endObject()
                    //可以按照城市排序，需要在其中再套一层，并且格式为keyword
                    .startObject("city")
                    .field("type","text")
                    .startObject("fields")
                    .startObject("raw")
                    .field("type","keyword")
                    .endObject()
                    .endObject()
                    .endObject()
                    //支持指定时间格式
                    .startObject("createTime")
                    .field("type","date")
                    .field("format","yyyy-MM-dd HH:mm:ss||yyyy-MM-dd||epoch_millis")
                    .endObject()
                    .endObject()
                    .endObject();
        } catch (IOException e) {
            e.printStackTrace();
        }
        putMappingRequest.source(builder);
        try {
            AcknowledgedResponse putMappingResponse = getRestClient().indices().putMapping(putMappingRequest, RequestOptions.DEFAULT);
            System.out.println(putMappingResponse);
            if (!putMappingResponse.isAcknowledged()){
                result = "接口执行失败";
            }else {
                result = "mapping“”已经存在";
            }
        } catch (IOException e) {
            result = "mapping创建接口异常";
        }

        return result;
    }

    @Override
    //将查询出的数据通过实体类映射到es中
    //注意：字段映射必须和es中的一致，可以直接映射，也可以转换为json映射
    public int saveDocumentByIndex(List<EsSearchEntity> esSearchList) {

        BulkRequest bulkRequest = new BulkRequest();
        Map<String,Object> map = new HashMap<>();
        int count = 0;
        for (EsSearchEntity esSearch:esSearchList){
            String json = JSON.toJSONString(esSearch);
            JSONObject jsonObject = JSONObject.parseObject(json);

            Date date = new Date();
            map.put("id",jsonObject.getString("id"));
            map.put("pics",jsonObject.getString("pics"));
            map.put("name",jsonObject.getString("name"));
            map.put("prices",jsonObject.getBigDecimal("prices"));
            map.put("city",jsonObject.getString("city"));
            //时间采用当前时间
            map.put("createTime",date);
            bulkRequest.add(new IndexRequest(IndexData.indexName,IndexData.type,esSearch.getBid()).source(map));
            bulkRequest.timeout("10m");
            try {
                BulkResponse bulkResponse = getRestClient().bulk(bulkRequest, RequestOptions.DEFAULT);
                count ++;
            } catch (IOException e) {
                log.info(esSearch.getBid() + "同步失败");
                e.printStackTrace();
            }
        }
        log.info("es同步完成,更新总记录数:" + count);
        return count;
    }
}

二：前台执行查询、分页、高亮

一：controller层

@RestController
@RequestMapping("es")
@Api(tags = "ES搜索")
public class ESController {

    @Autowired
    EsSearchService esSearchService;
    @PostMapping("search")
    //queryData中为查询的字段、排序字段
    //pageNum，pageSize是分页
    public Map<String,List<Map<String, Object>>> search( QueryData queryData,int pageNum,int pageSize){
        return esSearchService.searchProductByQuery(queryData,pageNum,pageSize);
    }
    }

二：实现类

@Override
public Map<String, List<Map<String, Object>>> searchProductByQuery(QueryData queryData,int pageNum,int pageSize) {
    //searchRequest 是用于查询
    SearchRequest searchRequest = new SearchRequest();
    //searchRequest1 用于统计查询的总数，由于Es中设置了from和size之后就无法查询出总数，所以就加了一次查询，如果大家有好的办法请务必告知于我，非常感谢！！！！
    SearchRequest searchRequest1 = new SearchRequest();
    //现在的版本已经不支持指定type啦，可以去掉，因为现在的type都是_doc
    searchRequest.indices(IndexData.indexName).types(IndexData.type);
    //将searchSourceBuilder加入到searchRequest中
    //由于好多的查询都用到了查询条件，所以我i直接将sourceBuilder进行了封装，用的时候可以直接调用，避免代码冗杂
    searchRequest.source(sourceBuilder(queryData,pageNum,pageSize));
    searchRequest1.source(sourceBuilderTotal(queryData));
//现在的Es的查询返回值都是map集合，需要用map来接
    List<Map<String, Object>> listTotal = searchResult(searchRequest1);
   同步执行
    List<Map<String, Object>> list = searchResult(searchRequest);
    Map<String, List<Map<String, Object>>> listMap = new HashMap<>();
//查询出来的值
   listMap.put("List", List);
   //查询出的总数
   listMap.put("total",listTotal.size);
    return listMap;
}

封装的sourceBuilder

//用于查询
public SearchSourceBuilder sourceBuilder(QueryData queryData,int pageNum,int pageSize) {

    SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();


        //开始搜索的位置
        searchSourceBuilder.from((pageNum-1)*pageSize);
        //搜索结果的数量大小
        searchSourceBuilder.size(pageSize);


    //设置超时时间
    searchSourceBuilder.timeout(new TimeValue(60, TimeUnit.SECONDS));

   
    //按照名称查询
    MatchQueryBuilder matchQueryBuilder = QueryBuilders.matchQuery("name", queryData.getQueryName());

    BoolQueryBuilder boolQueryBuilder = QueryBuilders.boolQuery();
    //嵌套查询，满足其一即可
    boolQueryBuilder.should(matchQueryBuilder);
   


    //按照价格区间排序
    if (null != queryData.getMinPrices() && null != queryData.getMaxPrices()) {
        RangeQueryBuilder queryBuilder = QueryBuilders
                .rangeQuery("prices")
                .from(queryData.getMinPrices())
                .to(queryData.getMaxPrices());
        searchSourceBuilder.query(queryBuilder);
    }


    if (StringUtils.equals("asc", queryData.getAsc())) {
        //按照价格升序
        searchSourceBuilder.sort(new FieldSortBuilder("prices")
                .order(SortOrder.ASC));
    } else if (StringUtils.equals("desc", queryData.getDesc())) {
        //按照价格降序
        searchSourceBuilder.sort(new FieldSortBuilder("prices")
                .order(SortOrder.DESC));
    } else if (StringUtils.isNotBlank(queryData.getSite())) {
        //按照地域排序
        searchSourceBuilder.sort(new FieldSortBuilder("city.raw")
                .order(SortOrder.ASC));
    }
    //此为高亮字段，作为封装类方法在这里被引用

    searchSourceBuilder.highlighter(highlight());

    //需要查询出来的字段
    String[] includeFields = new String[]{"id", "name", "city",  "pics", "createTime"};
    //不需要的字段
    String[] excludeFields = new String[]{""};
    searchSourceBuilder.fetchSource(includeFields, excludeFields);
    searchSourceBuilder.query(boolQueryBuilder);
    return searchSourceBuilder;
}

//获取总页数
public SearchSourceBuilder sourceBuilderTotal(QueryData queryData) {

    SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();
        //开始搜索的位置
        searchSourceBuilder.from(0);
        //搜索结果的数量大小
        searchSourceBuilder.size(10000);
   
    //按照商品/服务/解决方案名称查询
    MatchQueryBuilder matchQueryBuilder = QueryBuilders.matchQuery("pname", queryData.getQueryName());

   uilder boolQueryBuilder = QueryBuilders.boolQuery();
    //嵌套查询，满足其一即可
    boolQueryBuilder.should(matchQueryBuilder);
    searchSourceBuilder.query(boolQueryBuilder);
    return searchSourceBuilder;
}

封装的高亮字段

public HighlightBuilder highlight() {
    //设置高亮
    HighlightBuilder highlightBuilder = new HighlightBuilder();
    //设置高亮的前缀和后缀
    String preTags = "";
    String postTags = "";
    highlightBuilder.preTags(preTags);
    highlightBuilder.postTags(postTags);

    HighlightBuilder.Field pname = new HighlightBuilder.Field("name");
   
    highlightBuilder.field(name);
   return highlightBuilder;
}

重点来了！！！查询的结果集！！

public List<Map<String, Object>> searchResult(SearchRequest searchRequest) {
    List<Map<String, Object>> list = new ArrayList<>();
    List<String> fieldList = new ArrayList();
    //需要高亮的字段
    fieldList.add("pname");

    try {
        SearchResponse searchResponse = getRestClient().search(searchRequest, RequestOptions.DEFAULT);
        RestStatus status = searchResponse.status();
        log.info("状态：" + status);
        TimeValue took = searchResponse.getTook();
        log.info("执行时间：" + took);
        Boolean terminatedEarly = searchResponse.isTerminatedEarly();
        log.info("请求终止：" + terminatedEarly);
        boolean timedOut = searchResponse.isTimedOut();
        log.info("超时时间：" + timedOut);
        //获得响应的文档
        SearchHits hits = searchResponse.getHits();
        //迭代取出数据
        for (SearchHit hit : hits) {
            Map<String, Object> sourceAsMap = hit.getSourceAsMap();
            for (String field : fieldList()) {
                String keyValue = (String) sourceAsMap.get(field);
                HighlightField highlightFieldValue = hit.getHighlightFields().get(field);
                if (highlightFieldValue == null) {
                    sourceAsMap.put(field, keyValue);
                } else {
                    String highLightContent = highlightFieldValue.getFragments()[0].toString();
                    sourceAsMap.put(field, highLightContent);
                }
            }
            list.add(sourceAsMap);
        }
    } catch (IOException e) {
        e.printStackTrace();
    }
    return list;
}

结语

个人觉得自己看着API写虽然慢但是可以避免好多的版本冲突（因为现在网上大神分享的博客很多都是老版本的），而且还可以提升英语能力！
以上就是自己写的es查询，希望能对大家有所帮助！！！有好的建议或者批评，也欢迎大家留言或者与我联系！！！