公司在用 es 版本

7.14.2

jar 包引入

这里高于公司在用版本，从使用情况来看，基本上是有兼容的
compile("co.elastic.clients:elasticsearch-java:7.17.2")
// 项目存在低版本的 httpclient, 会导致 es 请求出现问题，所以引入了最新版本的 httpclient
compile("org.apache.httpcomponents:httpclient:4.5.13")

elasticSearch 官方链接

https://www.elastic.co/guide/en/elasticsearch/reference/7.17/index.html

配置

配置类

// ... 此处省略各种 import

@Configuration
@ConfigurationProperties(prefix = "demo.elasticsearch")
@RefreshScope
@RefreshBinder
public class EsConfig {

    private Integer port;

    private String host;

    private String username;

    private String password;

    @ApiModelProperty("第三方信息索引")
    private String oauthIndexName;

    @ApiModelProperty("第三方信息索引别名")
    private String oauthIndexAliasName;

    @ApiModelProperty("基本信息索引")
    private String accountIndexName;

    @ApiModelProperty("基本信息索引别名")
    private String accountIndexAliasName;

    @Bean
    public ElasticsearchClient getElasticSearchClient() {

        // 线下，线上都是有配置了访问账号的
        final CredentialsProvider credentialsProvider =
                new BasicCredentialsProvider();
        credentialsProvider.setCredentials(AuthScope.ANY,
                new UsernamePasswordCredentials(username, password));

        // Create the low-level client
        RestClientBuilder builder = RestClient.
                builder(new HttpHost(host, port))
                .setHttpClientConfigCallback(httpClientBuilder ->
                        httpClientBuilder.setDefaultCredentialsProvider(credentialsProvider)
                );

        RestClient restClient = builder.build();

        // Create the transport with a Jackson mapper
        ElasticsearchTransport transport = new RestClientTransport(
                restClient, new JacksonJsonpMapper());

        //这里只返回了 Java API Client
        return new ElasticsearchClient(transport);
    }

    public EsConfig(Integer port, String host, String username, String password, String oauthIndexName, String oauthIndexAliasName, String accountIndexName, String accountIndexAliasName) {
        this.port = port;
        this.host = host;
        this.username = username;
        this.password = password;
        this.oauthIndexName = oauthIndexName;
        this.oauthIndexAliasName = oauthIndexAliasName;
        this.accountIndexName = accountIndexName;
        this.accountIndexAliasName = accountIndexAliasName;
    }

    public EsConfig() {
    }

    public Integer getPort() {
        return port;
    }

    public void setPort(Integer port) {
        this.port = port;
    }

    public String getHost() {
        return host;
    }

    public void setHost(String host) {
        this.host = host;
    }

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public String getOauthIndexName() {
        return oauthIndexName;
    }

    public void setOauthIndexName(String oauthIndexName) {
        this.oauthIndexName = oauthIndexName;
    }

    public String getOauthIndexAliasName() {
        return oauthIndexAliasName;
    }

    public void setOauthIndexAliasName(String oauthIndexAliasName) {
        this.oauthIndexAliasName = oauthIndexAliasName;
    }

    public String getAccountIndexName() {
        return accountIndexName;
    }

    public void setAccountIndexName(String accountIndexName) {
        this.accountIndexName = accountIndexName;
    }

    public String getAccountIndexAliasName() {
        return accountIndexAliasName;
    }

    public void setAccountIndexAliasName(String accountIndexAliasName) {
        this.accountIndexAliasName = accountIndexAliasName;
    }
}

配置文件

demo: 
  elasticsearch:
      host: 127.0.0.1
      port: 9200
      username: "username"
      password: "password"
      oauth-index-name: "xxxx"
      oauth-index-alias-name: "xxxx"
      account-index-name: "yyyyy"
      account-index-alias-name: "yyyyy"

如何使用

High Level Rest Client 废弃

这个类，官方已废弃， 推荐在代码中使用 Java API Client ，所以在elasticSearch 配置类中， 只通过 @Bean 注入Java API Client

如何使用 Java API Client

插入新文档

官方链接

JAVA 语法示例

elasticsearchClient.index(i -> i
        .index("indexName")
        .id("文档id")
        .document("文档内容,  实例化后的对象")
);

更新文档

更新文档有2种方式，一种是通过文档id, 另外一种则是根据查询结果更新

通过文档id 更新

官方链接

JAVA 语法示例

Map<String, Object> updateMap = new HashMap<>();
updateMap.put("fieldName", "fieldValue")
elasticsearchClient.update(UpdateRequest.of(o -> o
        .index("indexName")
        .id("文档id")
        .doc(updateMap)), IndexUserInfo.class); // 这里要指定实体的 class 对象

通过查询条件更新

官方链接

JAVA 语法示例

UpdateByQueryRequest.Builder builder = new UpdateByQueryRequest.Builder();

// bool 是组合查询
// must 要求必须匹配
builder.query(q -> q.bool(b -> b
                .must(TermQuery.of(o -> o.field("fieldName1").value("fieldValue1"))._toQuery())
                .must(TermQuery.of(o -> o.field("fieldName2").value("fieldValue2"))._toQuery())
        )
);

// 这里通过脚本的方式去更新
Script.Builder scriptBuilder = new Script.Builder();

// InlineScript 
InlineScript.Builder inlineScriptBuilder = new InlineScript.Builder();
// 更新的内容, 根据自己需要替换成想要的操作
inlineScriptBuilder.source("ctx._source['is_deleted'] = 1");
// 接收 Inline 类型的脚步
scriptBuilder.inline(inlineScriptBuilder.build());
// 指定索引名
builder.index(esConfig.getOauthIndexName());
// scriptBuilder.build() 实例化 Script
builder.script(scriptBuilder.build());
try {
    elasticsearchClient.updateByQuery(builder.build());
} catch (Exception exception) {
    // ...
}

查询文档

官方链接

简易条件查询

JAVA 语法示例

SearchResponse<IndexUserInfo> indexUserInfoResponse = elasticsearchClient.search(s -> s
                .index("indexName")
                .query(q -> q.match(t -> t.field("username").query("xxxxx")))
        , IndexUserInfo.class);
Optional<Hit<IndexUserInfo>> first = indexUserInfoResponse.hits().hits().stream().findFirst();
return first.map(Hit::source).orElse(null);

查询文档总数

官方链接

JAVA 语法示例

CountRequest.Builder builder = new CountRequest.Builder();
builder.index("indexName");
CountResponse count = elasticsearchClient.count(builder.build());
return count.count();

持续更新中