elastic客户端TransportClient的使用

时间:2021-02-17 20:39:53

  关于TransportClient,elastic计划在Elasticsearch 7.0中弃用TransportClient,并在8.0中完全删除它。后面,应该使用Java高级REST客户端,它执行HTTP请求而不是序列化的Java请求。Java客户端主要用途有:

  (1)在现有集群上执行标准索引,获取,删除和搜索操作

  (2)在正在运行的集群上执行管理任务

  获取Elasticsearch客户端最常用方法是创建连接到群集的TransportClient。

maven依赖

  <dependency>
    <groupId>org.elasticsearch.client</groupId>
    <artifactId>transport</artifactId>
    <version>6.4.3</version>
  </dependency>

  客户端必须具有与群集中的节点相同的主要版本(例如2.x或5.x)。客户端可以连接到具有不同次要版本(例如2.3.x)的群集,但可能不支持新功能。理想情况下,客户端应具有与群集相同的版本。此博客目前正在使用的版本是6.4.3。

获取TransportClient

  TransportClient使用传输模块远程连接到Elasticsearch集群。它不加入集群,而只是获取一个或多个初始传输地址,并在每个操作上以循环方式与它们通信。

import org.elasticsearch.client.transport.TransportClient;
import org.elasticsearch.cluster.node.DiscoveryNode;
import org.elasticsearch.common.settings.Settings;
import org.elasticsearch.common.transport.TransportAddress;
import org.elasticsearch.transport.client.PreBuiltTransportClient; import java.net.InetAddress;
import java.net.UnknownHostException; public class Elasticsearch {
public static void main(String[] args) throws UnknownHostException {
//on startup
TransportClient client = new PreBuiltTransportClient(Settings.EMPTY)
.addTransportAddress(new TransportAddress(InetAddress.getByName("127.0.0.1"), 9300));
//继续添加其他地址
//on shutdown
client.close();
}
}

  如果出现:

elastic客户端TransportClient的使用

  说明需要配置日志

  maven依赖

<dependency>
<groupId>org.apache.logging.log4j</groupId>
<artifactId>log4j-core</artifactId>
<version>2.11.1</version>
</dependency> 然后再resources里面添加log4j2.properties,内容如下:
appender.console.type = Console
appender.console.name = console
appender.console.layout.type = PatternLayout rootLogger.level = info
rootLogger.appenderRef.console.ref = console

  如果出现"Exception in thread "main" java.lang.NoSuchMethodError: org.apache.logging.log4j.Logger.debug(Ljava/lang/String;Ljava/lang/Object;)", 则说明版本冲突,或者引的包是错的。

  请注意,如果使用集群名称不是默认的“elasticsearch”,则必须设置集群名称, 通过对Settings经行设置:

Settings settings = Settings.builder()
.put("cluster.name", "myClusterName").build();
TransportClient client = new PreBuiltTransportClient(settings);
//Add transport addresses and do something with the client...

  如果开启嗅探功能,即自动检测集群内其他的节点和新加入的节点,不需要全部都是用addTransportAddress添加,设置如下:

Settings settings = Settings.builder()
.put("client.transport.sniff", true).build();
TransportClient client = new PreBuiltTransportClient(settings);

  

Document APIs

  Single document APIs

  (1)Index api

import com.fasterxml.jackson.core.JsonProcessingException;
import org.elasticsearch.action.index.IndexResponse;
import org.elasticsearch.client.transport.TransportClient;
import org.elasticsearch.common.settings.Settings;
import org.elasticsearch.common.transport.TransportAddress;
import org.elasticsearch.common.xcontent.XContentType;
import org.elasticsearch.rest.RestStatus;
import org.elasticsearch.transport.client.PreBuiltTransportClient; import java.net.InetAddress;
import java.net.UnknownHostException;
import java.util.Date;
import java.util.HashMap;
import java.util.Map; public class Elasticsearch {
public static void main(String[] args) throws UnknownHostException, JsonProcessingException {
//on startup
TransportClient client = new PreBuiltTransportClient(Settings.EMPTY)
.addTransportAddress(new TransportAddress(InetAddress.getByName("127.0.0.1"), 9300));
//继续添加其他地址
Map<String, Object> json = new HashMap<String, Object>();
json.put("user", "kimchy");
json.put("postDate", new Date());
json.put("message", "trying out Elasticsearch");
     // index--twitter type--_doc id--1
IndexResponse indexResponse = client.prepareIndex("twitter", "_doc", "1").setSource(json, XContentType.JSON).get();
// Index name
String _index = indexResponse.getIndex();
// Type name
String _type = indexResponse.getType();
// Document ID (generated or not)
String _id = indexResponse.getId();
// Version (if it's the first time you index this document, you will get: 1)
long _version = indexResponse.getVersion();
// status has stored current instance statement.
RestStatus status = indexResponse.status();
//on shutdown
client.close();
}
}

  实现了数据的插入

  (2)GET API

  get API允许根据其id从索引中获取类型化的JSON文档。以下示例从名为twitter的索引中获取JSON文档,该类型名为_doc`,id值为1:

import com.fasterxml.jackson.core.JsonProcessingException;
import org.elasticsearch.action.get.GetRequestBuilder;
import org.elasticsearch.action.get.GetResponse;
import org.elasticsearch.action.index.IndexResponse;
import org.elasticsearch.client.transport.TransportClient;
import org.elasticsearch.common.settings.Settings;
import org.elasticsearch.common.transport.TransportAddress;
import org.elasticsearch.common.xcontent.XContentType;
import org.elasticsearch.rest.RestStatus;
import org.elasticsearch.transport.client.PreBuiltTransportClient; import java.net.InetAddress;
import java.net.UnknownHostException;
import java.util.Date;
import java.util.HashMap;
import java.util.Map; public class Elasticsearch {
public static void main(String[] args) throws UnknownHostException, JsonProcessingException {
//on startup
TransportClient client = new PreBuiltTransportClient(Settings.EMPTY)
.addTransportAddress(new TransportAddress(InetAddress.getByName("127.0.0.1"), 9300));
//继续添加其他地址 GetResponse documentFields = client.prepareGet("twitter", "_doc", "1").get();
System.out.println(documentFields.getIndex());
System.out.println(documentFields.getType());
System.out.println(documentFields.getId());
System.out.println(documentFields.getSourceAsString());
//on shutdown
client.close();
}
}

输出结果:

elastic客户端TransportClient的使用

  (3)DELETE  API

import com.fasterxml.jackson.core.JsonProcessingException;
import org.elasticsearch.action.delete.DeleteResponse;
import org.elasticsearch.action.get.GetRequestBuilder;
import org.elasticsearch.action.get.GetResponse;
import org.elasticsearch.action.index.IndexResponse;
import org.elasticsearch.client.transport.TransportClient;
import org.elasticsearch.common.settings.Settings;
import org.elasticsearch.common.transport.TransportAddress;
import org.elasticsearch.common.xcontent.XContentType;
import org.elasticsearch.rest.RestStatus;
import org.elasticsearch.transport.client.PreBuiltTransportClient; import java.net.InetAddress;
import java.net.UnknownHostException;
import java.util.Date;
import java.util.HashMap;
import java.util.Map; public class Elasticsearch {
public static void main(String[] args) throws UnknownHostException, JsonProcessingException {
//on startup
TransportClient client = new PreBuiltTransportClient(Settings.EMPTY)
.addTransportAddress(new TransportAddress(InetAddress.getByName("127.0.0.1"), 9300));
//继续添加其他地址 DeleteResponse response = client.prepareDelete("twitter", "_doc", "1").get();
System.out.println(response.toString());
//on shutdown
client.close();
}
}

  结果如下:

elastic客户端TransportClient的使用

  (4)Delete By Query API

import com.fasterxml.jackson.core.JsonProcessingException;
import org.elasticsearch.action.delete.DeleteResponse;
import org.elasticsearch.action.get.GetRequestBuilder;
import org.elasticsearch.action.get.GetResponse;
import org.elasticsearch.action.index.IndexResponse;
import org.elasticsearch.client.transport.TransportClient;
import org.elasticsearch.common.settings.Settings;
import org.elasticsearch.common.transport.TransportAddress;
import org.elasticsearch.common.xcontent.XContentType;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.index.reindex.BulkByScrollResponse;
import org.elasticsearch.index.reindex.DeleteByQueryAction;
import org.elasticsearch.rest.RestStatus;
import org.elasticsearch.transport.client.PreBuiltTransportClient; import java.net.InetAddress;
import java.net.UnknownHostException;
import java.util.Date;
import java.util.HashMap;
import java.util.Map; public class Elasticsearch {
public static void main(String[] args) throws UnknownHostException, JsonProcessingException {
//on startup
TransportClient client = new PreBuiltTransportClient(Settings.EMPTY)
.addTransportAddress(new TransportAddress(InetAddress.getByName("127.0.0.1"), 9300));
//继续添加其他地址 BulkByScrollResponse response = DeleteByQueryAction.INSTANCE.newRequestBuilder(client)
.filter(QueryBuilders.matchQuery("user", "kimchy"))
.source("twitter")
.get();
long deleted = response.getDeleted(); //on shutdown
client.close();
}
}

以刚才那条index->twitter为例,此api先查询出满足条件的所有index,然后调用getDeleted函数删除相关的数据。

  (5)Update API

  可以使用prepareUpdate()方法

import com.fasterxml.jackson.core.JsonProcessingException;
import org.elasticsearch.action.delete.DeleteResponse;
import org.elasticsearch.action.get.GetRequestBuilder;
import org.elasticsearch.action.get.GetResponse;
import org.elasticsearch.action.index.IndexResponse;
import org.elasticsearch.client.transport.TransportClient;
import org.elasticsearch.common.settings.Settings;
import org.elasticsearch.common.transport.TransportAddress;
import org.elasticsearch.common.xcontent.XContentType;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.index.reindex.BulkByScrollResponse;
import org.elasticsearch.index.reindex.DeleteByQueryAction;
import org.elasticsearch.rest.RestStatus;
import org.elasticsearch.transport.client.PreBuiltTransportClient; import java.io.IOException;
import java.net.InetAddress;
import java.net.UnknownHostException;
import java.util.Date;
import java.util.HashMap;
import java.util.Map; import static org.elasticsearch.common.xcontent.XContentFactory.jsonBuilder; public class Elasticsearch {
public static void main(String[] args) throws IOException {
//on startup
TransportClient client = new PreBuiltTransportClient(Settings.EMPTY)
.addTransportAddress(new TransportAddress(InetAddress.getByName("127.0.0.1"), 9300));
//继续添加其他地址 client.prepareUpdate("twitter", "_doc", "1")
.setDoc(jsonBuilder()
.startObject()
.field("user", "chenmz")
.endObject())
.get();
//on shutdown
client.close();
}
}

用kibana查询后:

elastic客户端TransportClient的使用

发现名字已经发生改变,更改成功。

  Multi-document APIs

  (1)Multi Get API

  multi get API允许根据索引和id获取文档列表,往elastic中添加id为2的document,然后查询:

import com.fasterxml.jackson.core.JsonProcessingException;
import org.elasticsearch.action.delete.DeleteResponse;
import org.elasticsearch.action.get.GetRequestBuilder;
import org.elasticsearch.action.get.GetResponse;
import org.elasticsearch.action.get.MultiGetItemResponse;
import org.elasticsearch.action.get.MultiGetResponse;
import org.elasticsearch.action.index.IndexResponse;
import org.elasticsearch.client.transport.TransportClient;
import org.elasticsearch.common.settings.Settings;
import org.elasticsearch.common.transport.TransportAddress;
import org.elasticsearch.common.xcontent.XContentType;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.index.reindex.BulkByScrollResponse;
import org.elasticsearch.index.reindex.DeleteByQueryAction;
import org.elasticsearch.rest.RestStatus;
import org.elasticsearch.transport.client.PreBuiltTransportClient; import java.io.IOException;
import java.net.InetAddress;
import java.net.UnknownHostException;
import java.util.Date;
import java.util.HashMap;
import java.util.Map; import static org.elasticsearch.common.xcontent.XContentFactory.jsonBuilder; public class Elasticsearch {
public static void main(String[] args) throws IOException {
//on startup
TransportClient client = new PreBuiltTransportClient(Settings.EMPTY)
.addTransportAddress(new TransportAddress(InetAddress.getByName("127.0.0.1"), 9300));
//继续添加其他地址 MultiGetResponse multiGetItemResponses = client.prepareMultiGet()
.add("twitter", "_doc", "1", "2")
.get();
for (MultiGetItemResponse itemResponse : multiGetItemResponses) {
GetResponse response = itemResponse.getResponse();
if (response.isExists()) {
String json = response.getSourceAsString();
System.out.println(json);
}
} //on shutdown
client.close();
}
}

运行结果:

elastic客户端TransportClient的使用

  (2)Bulk API

  批量API允许在单个请求中索引和删除多个文档。以下演示增加多个索引。

import com.fasterxml.jackson.core.JsonProcessingException;
import org.elasticsearch.action.bulk.BulkRequestBuilder;
import org.elasticsearch.action.bulk.BulkResponse;
import org.elasticsearch.action.delete.DeleteResponse;
import org.elasticsearch.action.get.GetRequestBuilder;
import org.elasticsearch.action.get.GetResponse;
import org.elasticsearch.action.get.MultiGetItemResponse;
import org.elasticsearch.action.get.MultiGetResponse;
import org.elasticsearch.action.index.IndexResponse;
import org.elasticsearch.client.transport.TransportClient;
import org.elasticsearch.common.settings.Settings;
import org.elasticsearch.common.transport.TransportAddress;
import org.elasticsearch.common.xcontent.XContentType;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.index.reindex.BulkByScrollResponse;
import org.elasticsearch.index.reindex.DeleteByQueryAction;
import org.elasticsearch.rest.RestStatus;
import org.elasticsearch.transport.client.PreBuiltTransportClient; import java.io.IOException;
import java.net.InetAddress;
import java.net.UnknownHostException;
import java.util.Date;
import java.util.HashMap;
import java.util.Map; import static org.elasticsearch.common.xcontent.XContentFactory.jsonBuilder; public class Elasticsearch {
public static void main(String[] args) throws IOException {
//on startup
TransportClient client = new PreBuiltTransportClient(Settings.EMPTY)
.addTransportAddress(new TransportAddress(InetAddress.getByName("127.0.0.1"), 9300));
//继续添加其他地址 BulkRequestBuilder bulkRequest = client.prepareBulk();
bulkRequest.add(client.prepareIndex("twitter", "_doc", "3")
.setSource(jsonBuilder()
.startObject()
.field("user", "zhangsan")
.field("postDate", new Date())
.field("message", "trying out Elasticsearch")
.endObject()
)
); bulkRequest.add(client.prepareIndex("twitter", "_doc", "4")
.setSource(jsonBuilder()
.startObject()
.field("user", "lisi")
.field("postDate", new Date())
.field("message", "another post")
.endObject()
)
); BulkResponse bulkResponse = bulkRequest.get();
if (bulkResponse.hasFailures()) {
// process failures by iterating through each bulk response item
} //on shutdown
client.close();
}
}

  然后查询,得到如下的结果:

elastic客户端TransportClient的使用

  说明批量添加索引成功。

  (4)Reindex API

   可以提供查询以过滤应该从源索引到目标索引重新索引哪些文档。就是在已有的索引当中选择一些放到另一个索引之中。

import com.fasterxml.jackson.core.JsonProcessingException;
import org.elasticsearch.action.bulk.BulkRequestBuilder;
import org.elasticsearch.action.bulk.BulkResponse;
import org.elasticsearch.action.delete.DeleteResponse;
import org.elasticsearch.action.get.GetRequestBuilder;
import org.elasticsearch.action.get.GetResponse;
import org.elasticsearch.action.get.MultiGetItemResponse;
import org.elasticsearch.action.get.MultiGetResponse;
import org.elasticsearch.action.index.IndexResponse;
import org.elasticsearch.client.transport.TransportClient;
import org.elasticsearch.common.settings.Settings;
import org.elasticsearch.common.transport.TransportAddress;
import org.elasticsearch.common.xcontent.XContentType;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.index.reindex.BulkByScrollResponse;
import org.elasticsearch.index.reindex.DeleteByQueryAction;
import org.elasticsearch.index.reindex.ReindexAction;
import org.elasticsearch.rest.RestStatus;
import org.elasticsearch.transport.client.PreBuiltTransportClient; import java.io.IOException;
import java.net.InetAddress;
import java.net.UnknownHostException;
import java.util.Date;
import java.util.HashMap;
import java.util.Map; import static org.elasticsearch.common.xcontent.XContentFactory.jsonBuilder; public class Elasticsearch {
public static void main(String[] args) throws IOException {
//on startup
TransportClient client = new PreBuiltTransportClient(Settings.EMPTY)
.addTransportAddress(new TransportAddress(InetAddress.getByName("127.0.0.1"), 9300));
//继续添加其他地址
BulkByScrollResponse response = ReindexAction.INSTANCE.newRequestBuilder(client).source("_all")
.destination("target_index")
.filter(QueryBuilders.matchQuery("user", "lisi")).get();
System.out.println(response.toString()); //on shutdown
client.close();
}
}

其中.source后面可以添加具体的索引.source("index1", "index2");等。

用Kibana查询结果如下:

elastic客户端TransportClient的使用

  生成一个target_index,下面多了一条user为lisi的document

ps:这边的主要面向Document APIs, 其实呢还有很多其他的api, elastic封装了很多的其他api也能达到同样的效果。