RestClient操作文档

初始化RestClient

在elasticsearch提供的API中，与elasticsearch一切交互都封装在一个名为RestHighLevelClient的类中，必须先完成这个对象的初始化，建立与elasticsearch的连接。

分为三步：

1）引入es的RestHighLevelClient依赖：

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

2）因为SpringBoot默认的ES可能版本不一致，所以我们需要覆盖默认的ES版本：

<properties>
    <java.version>1.8</java.version>
    <elasticsearch.version>7.12.1</elasticsearch.version>
</properties>

3）初始化RestHighLevelClient：

初始化的代码如下：

//可以使用配置类交给ioc
@Configuration
public class ESConfig {
    @Bean
    public RestHighLevelClient restHighLevelClient() {
        return new RestHighLevelClient(
                RestClient.builder(
                        new HttpHost("00.0xx.x0x.xxx", 9200, "http")
                ));
    }
}

索引库相关操作

@SpringBootTest
class HotelIndexTest {

    @Autowired
    private RestHighLevelClient client;

//创建索引库
    @Test
    void testCreateIndex() throws Exception {
        // 1.准备Request      PUT /hotel
        CreateIndexRequest request = new CreateIndexRequest("hotel");
        // 2.准备请求参数
        request.source(MAPPING_TEMPLATE, XContentType.JSON);
        // 3.发送请求
        client.indices().create(request, RequestOptions.DEFAULT);

    }
//删除索引库
    @Test
    void testDeleteIndex() throws IOException {
        // 1.准备Request
        DeleteIndexRequest request = new DeleteIndexRequest("hotel");
        // 2.判断存不存在
        GetIndexRequest indexRequest = new GetIndexRequest("hotel");
        boolean exists = client.indices().exists(indexRequest, RequestOptions.DEFAULT);
        if (!exists) {
            System.out.println("不存在哦！");
            return;
        }
        // 3.发送请求
        client.indices().delete(request, RequestOptions.DEFAULT);
    }
//判断是否存在
    @Test
    void testGetIndex() throws IOException {
        GetIndexRequest request = new GetIndexRequest("hotel");
        boolean exists = client.indices().exists(request, RequestOptions.DEFAULT);
        System.out.println(exists ? "存在" : "不存在");
    }

}

Document文档操作

@SpringBootTest
class HotelDocumentTest {

    @Autowired
    private RestHighLevelClient client;

    @Autowired
    private IHotelService hotelService;

    @Test
    void testAddDoc() throws IOException {
        //1.查询数据库hotel数据
        Hotel hotel = hotelService.getById(61083);
        //2.转换为HotelDoc
        HotelDoc hotelDoc = new HotelDoc(hotel);
        //3.转换成json
        String jsonString = JSONObject.toJSONString(hotelDoc);
        //4.准备request
        IndexRequest request = new IndexRequest("hotel").id(hotelDoc.getId().toString());
        //5.这是发送的文档
        request.source(jsonString, XContentType.JSON);
        client.index(request, RequestOptions.DEFAULT);
    }

    @Test
    void testGetDoc() throws IOException {
        //1.准备Request
        GetRequest request = new GetRequest("hotel").id("61083");
        //2.发送请求
        GetResponse response = client.get(request, RequestOptions.DEFAULT);
        //3.解析响应
        String source = response.getSourceAsString();
        //json转换成对象
        HotelDoc hotelDoc = JSON.parseObject(source, HotelDoc.class);

        System.out.println(hotelDoc);
    }

    @Test
    void testDeleteDoc() throws IOException {
        DeleteRequest request = new DeleteRequest("hotel", "61083");
        client.delete(request, RequestOptions.DEFAULT);
    }

    @Test
    void testUpdateDoc() throws IOException {
        UpdateRequest request = new UpdateRequest("hotel", "61083");
        request.doc(
                "price", "999"
        );
        client.update(request, RequestOptions.DEFAULT);
    }

    @Test
    void testBulkNewRequest() throws IOException {
        //分页打包添加
        int page = 1;
        int size = 100;
        Page<Hotel> hotelPage = hotelService.page(new Page<>(page, size));

        for (long i = 1; i <= hotelPage.getPages(); i++) {
            Page<Hotel> hotelData = hotelService.page(new Page<>(i, size));
            BulkRequest bulkRequest = new BulkRequest();
            for (Hotel hotel : hotelData.getRecords()) {
                HotelDoc hotelDoc = new HotelDoc(hotel);
                String hotelString = JSONObject.toJSONString(hotelDoc);
                bulkRequest.add(new IndexRequest("hotel")
                        .id(hotelDoc.getId().toString())
                        .source(hotelString, XContentType.JSON));
            }
            client.bulk(bulkRequest, RequestOptions.DEFAULT);
        }
    }
}