es 6版本以后 改为restClient请求demo

本文示例es版本为6.4.3，理论上支持到最新的7.x

es在6.3.x版本后不支持transport版本，改为支持restClient, 底层调用依旧为httpclient,只是基于es请求包装了一层。

restClient分为hign版本和low版本，暂时只调试了hign版本

经过一天的调试，写了一个简单的demo记录一下。

疑问：restClient底层依旧为长连接，那么我如果不长期close情况的下，会不会造成什么影响呢

pom:

<!-- es pom start-->
        <dependency>
            <groupId>org.elasticsearch.client</groupId>
            <artifactId>elasticsearch-rest-high-level-client</artifactId>
            <version>${es.version}</version>
        </dependency>
        <dependency>
            <groupId>org.elasticsearch.client</groupId>
            <artifactId>elasticsearch-rest-client</artifactId>
            <version>${es.version}</version>
        </dependency>
        <dependency>
            <groupId>org.elasticsearch</groupId>
            <artifactId>elasticsearch</artifactId>
            <version>${es.version}</version>
        </dependency>
        <!--如果项目本身的依赖低于该版本时，restClient会创建失败-->
        <dependency>
        <groupId>org.apache.httpcomponents</groupId>
        <artifactId>httpclient</artifactId>
        <version>4.5.3</version>
        </dependency>
        <!-- es pom emd-->

demo代码

/**
 * @Desc:
 * @Auth: li
 * @Date: 2020/9/1
 **/
@Component
public class RestClient {

    protected static final Logger LOG = LoggerFactory.getLogger(RestClient.class);

    /**
     * 相关配置信息Test
     */
    public static String URL = "127.0.0.1";
    public static int PORT = 9300;
    public static String USERNAME = "es-test";
    public static String PASSWORD = "xxx";


    private static RestHighLevelClient client;

    @PostConstruct
    public void init() {
        client = getClient();
    }

    public RestHighLevelClient getClient() {
        if (Objects.nonNull(client)) {
            return client;
        }
        synchronized (RestClient.class) {
            try {
                RestClientBuilder builder = org.elasticsearch.client.RestClient.builder(new HttpHost(URL, PORT, "http"));
                //没有用户名 密码的话 这块可以忽略 直接调用最后一行
                CredentialsProvider credentialsProvider = new BasicCredentialsProvider();
                credentialsProvider.setCredentials(AuthScope.ANY, new UsernamePasswordCredentials(USERNAME, PASSWORD));
                builder.setHttpClientConfigCallback(f -> f.setDefaultCredentialsProvider(credentialsProvider));
                client = new RestHighLevelClient(builder);
            } catch (Exception e) {
                e.printStackTrace();
            }
            return client;
        }
    }


    /**
     * getApi
     *
     * @param index
     * @param type
     * @param id
     * @param includes 返回的字段集合 不能为空
     * @throws Exception
     */
    public Map<String, Object> getDocById(String index, String type, String id, List<String> includes) throws Exception {
        GetRequest request = new GetRequest(index, type, id);
        //可选参数设置
        request.fetchSourceContext(FetchSourceContext.DO_NOT_FETCH_SOURCE);
        FetchSourceContext fetchSourceContext = new FetchSourceContext(true, includes.toArray(new String[0]), null);
        request.fetchSourceContext(fetchSourceContext);
        //同步执行
        GetResponse getResponse = getClient().get(request, RequestOptions.DEFAULT);
        LOG.debug("开始获取doc信息,index-{},id-{},result-{}", index, id, JSON.toJSONString(getResponse.getSource()));
        return getResponse.getSource();
    }

    /**
     * 删除doc
     *
     * @param index
     * @param type
     * @param id
     * @throws Exception
     */
    public void deleteDocById(String index, String type, String id) throws Exception {
        DeleteRequest request = new DeleteRequest(index, type, id);
        DeleteResponse deleteResponse = getClient().delete(request, RequestOptions.DEFAULT);
        LOG.debug("开始删除数据id-{},返回值-{}", id, JSON.toJSONString(deleteResponse.getResult()));
    }

    /**
     * 新增doc
     *
     * @param index
     * @param type
     * @param jsonString
     * @return
     * @throws Exception
     */
    public String addDoc(String index, String type, String jsonString) throws Exception {
        IndexRequest indexRequest = new IndexRequest(index, type);
        indexRequest.source(jsonString, XContentType.JSON);
        //同步执行
        IndexResponse indexResponse = getClient().index(indexRequest, RequestOptions.DEFAULT);
        LOG.debug("新增doc,index-{},context-{},resultId-{}", index, jsonString, indexResponse.getId());
        return indexResponse.getId();
    }

    /**
     * 更新doc
     *
     * @param index
     * @param type
     * @param id
     * @param updateMap
     * @return
     * @throws Exception
     */
    public void updateDocById(String index, String type, String id, Map<String, String> updateMap) throws Exception {
        UpdateRequest updateRequest = new UpdateRequest(index, type, id);
        updateRequest.doc(updateMap, XContentType.JSON);
        //同步执行
        UpdateResponse updateResponse = getClient().update(updateRequest, RequestOptions.DEFAULT);
        LOG.debug("更新doc,index-{},id-{},updateJson-{}", index, id, JSON.toJSONString(updateMap));
    }

    public static void main(String[] args) throws Exception {
        Map<String, Object> docById = new RestClient().getDocById("test202002111215", "doc", "97x3MnABuFEFg1xQqGnQ", Lists.newArrayList("title", "url", "remark"));
        System.out.println(JSON.toJSONString(docById));
    }


public <T> List<T>  select(String key,String value,Integer size,Class<T> T){
        SearchRequest request = new SearchRequest();
        SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();
        searchSourceBuilder.query(QueryBuilders.termQuery(key, value));
        if(Objects.nonNull(size)) {
            searchSourceBuilder.from(0);
            searchSourceBuilder.size(size);
        }
        request.source(searchSourceBuilder);
        List<T> result = Lists.newArrayList();
        try {
            SearchResponse response = getClient().search(request, RequestOptions.DEFAULT);
            SearchHit[] results = response.getHits().getHits();
            for(SearchHit hit : results){
                String sourceAsString = hit.getSourceAsString();
                if (StringUtils.isNotBlank(sourceAsString)) {
                    result.add(JSONObject.parseObject(sourceAsString, T));
                }
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
        return result;
    }
}