如何在 Spring Data ES 3.2.0.M1 中使用 High Level Rest Client

Question

Spring Data ES 3.2.0.M1 仍然使用旧的TransportClient 而不是HighLevelRestClient

Spring Data ES 3.2.0.M1 支持 High Level Rest Client，参见Add support for Java High Level REST Client。我已将 Spring Data ES 3.2.0.M1 添加到 SB2 应用程序：

        <dependency>
            <groupId>org.springframework.data</groupId>
            <artifactId>spring-data-elasticsearch</artifactId>
            <version>3.2.0.M1</version>
        </dependency>

但是，仍然使用TransportClient。有两个迹象表明：启动异常：

o.e.transport.netty4.Netty4Transport     : exception caught on transport layer [NettyTcpChannel{localAddress=/127.0.0.1:61171, remoteAddress=localhost/127.0.0.1:8085}], closing connection

io.netty.handler.codec.DecoderException: java.io.StreamCorruptedException: invalid internal transport message format, got (48,54,54,50)
    at io.netty.handler.codec.ByteToMessageDecoder.callDecode(ByteToMessageDecoder.java:472) ~[netty-codec-4.1.33.Final.jar:4.1.33.Final]

调用ElasticsearchTemplate时的异常堆栈跟踪：

    at org.elasticsearch.client.transport.TransportClientNodesService.ensureNodesAreAvailable(TransportClientNodesService.java:349)
    at org.elasticsearch.client.transport.TransportClientNodesService.execute(TransportClientNodesService.java:247)
    at org.elasticsearch.client.transport.TransportProxyClient.execute(TransportProxyClient.java:60)
    at org.elasticsearch.client.transport.TransportClient.doExecute(TransportClient.java:382)
    at org.elasticsearch.client.support.AbstractClient.execute(AbstractClient.java:395)
    at org.elasticsearch.client.support.AbstractClient.execute(AbstractClient.java:384)
    at org.elasticsearch.action.ActionRequestBuilder.execute(ActionRequestBuilder.java:46)
    at org.springframework.data.elasticsearch.core.ElasticsearchTemplate.getSearchResponse(ElasticsearchTemplate.java:947)

是否有任何配置参数告诉 Spring Data ES 切换到新的 High Level Rest Client？文档对此只字未提。

附： Spring Data ES 3.2.0.M1 有 6.4.3 ES 客户端版本：

Caused by: java.io.StreamCorruptedException: invalid internal transport message format, got (48,54,54,50)
    at org.elasticsearch.transport.TcpTransport.validateMessageHeader(TcpTransport.java:1327) ~[elasticsearch-6.4.3.jar:6.4.3]
    at org.elasticsearch.transport.netty4.Netty4SizeHeaderFrameDecoder.decode(Netty4SizeHeaderFrameDecoder.java:36) ~[transport-netty4-client-6.4.3.jar:6.4.3]
    at io.netty.handler.codec.ByteToMessageDecoder.decodeRemovalReentryProtection(ByteToMessageDecoder.java:502) ~[netty-codec-4.1.33.Final.jar:4.1.33.Final]
    at io.netty.handler.codec.ByteToMessageDecoder.callDecode(ByteToMessageDecoder.java:441) ~[netty-codec-4.1.33.Final.jar:4.1.33.Final]
    ... 20 common frames omitted

后端运行6.4.2版本：

bash-4.4$ curl http://127.0.0.1:8085
{
  "name" : "NA17WWR",
  "cluster_name" : "494164851665",
  "cluster_uuid" : "7t3LoK7PRp-ur6FyxSmHwQ",
  "version" : {
    "number" : "6.4.2",
    "build_flavor" : "oss",
    "build_type" : "zip",
    "build_hash" : "04711c2",
    "build_date" : "2018-10-16T09:16:35.059415Z",
    "build_snapshot" : false,
    "lucene_version" : "7.4.0",
    "minimum_wire_compatibility_version" : "5.6.0",
    "minimum_index_compatibility_version" : "5.0.0"
  },
  "tagline" : "You Know, for Search"
}

Answer 1

正如您所指的问题中所述，高级 REST 客户端在 ElasticsearchRestTemplate（请参阅 PR #216）而不是在 ElasticsearchTemplate 中可用，出于向后兼容性的原因，它们将保留到 ES 7。

您可以使用以下配置创建一个：

<bean name="elasticsearchTemplate"
      class="org.springframework.data.elasticsearch.core.ElasticsearchRestTemplate">
    <constructor-arg name="client" ref="restClient"/>
</bean>

<elasticsearch:rest-client id="restClient"/>