6

I am trying to use Java High Level Rest Client in Adobe Experience Manager to finish project of comparison between Lucene, Solr and Elasticsearch search engines.

I am having some problems with elasticsearh implementation. Here is the code:

  • Dependency in the parent pom.xml (the same is defined in core pom.xml)

    <!-- Elasticseach dependencies -->
<dependency>
    <groupId>org.elasticsearch.client</groupId>
    <artifactId>elasticsearch-rest-high-level-client</artifactId>
    <version>7.4.0</version>
</dependency>

  • The only line of code that I am using that is from dependencies above

    try (RestHighLevelClient client = new 
RestHighLevelClient(RestClient.builder(new HttpHost(server, port, 
protocol),
  new HttpHost(server, secondPort, protocol)));)
{

}
catch (ElasticsearchException e)
{
    LOG.error("Exception: " + e);
}

protocol = "http", server = "localhost", port = 9200, secondPort = 9201

  • Error

enter image description here

  • Dependencies from IntelliJ

enter image description here

I know that there is usually problem with dependencies versions, but all are 7.4.0 in this case. Also elasticsearch 7.4.0v is running locally on 3 nodes.

This project is done on We.Retail project so it is easy to replicate. Also all the code with this error is available here: https://github.com/tadijam64/search-engines-comparison-on-we-retail/tree/elasticsearch-integration AEM 6.4v.

Any info or idea is appreciated.

UPDATE I tried with adding the following to embed these dependencies externally since they are not OSGi dependencies:

<build>
        <plugins>
            <plugin>
                <groupId>org.apache.felix</groupId>
                <artifactId>maven-scr-plugin</artifactId>
            </plugin>
            <plugin>
                <groupId>org.apache.felix</groupId>
                <artifactId>maven-bundle-plugin</artifactId>
                <extensions>true</extensions>
                <configuration>
                    <instructions>
                        <Embed-Dependency>org.apache.servicemix.bundles.solr-solrj, log4j, noggit, zookeeper,
                            elasticsearch-rest-high-level-client
                        </Embed-Dependency>
                        <Embed-Transitive>true</Embed-Transitive>
                        <Embed-Directory>OSGI-INF/lib</Embed-Directory>
                        <Export-Package>we.retail.core.model*</Export-Package>
                        <Import-Package>
                            *;resolution:=optional
                        </Import-Package>
                        <Private-Package>we.retail.core*</Private-Package>
                        <Sling-Model-Packages>
                            we.retail.core.model
                        </Sling-Model-Packages>
                    </instructions>
                </configuration>
            </plugin>
        </plugins>
    </build>

The error remains. I also tried adding it to the "export-package", but nothing helps.

And by Elasticsearch documentation, all I need to use Elasticsearch is 

<dependency>
    <groupId>org.elasticsearch.client</groupId>
    <artifactId>elasticsearch-rest-high-level-client</artifactId>
    <version>7.4.0</version>
</dependency>

but then NoClassDefFoundErrors occurs. It seems like a problem with transitive dependencies maybe. Not sure, but any idea is appreciated.

Some other suggestions can be found here: https://forums.adobe.com/thread/2653586

I have also tried adding it's transitive dependencies like org.elasticsearch and org.elasticsearch.client, but it does not work. The same error, just other class.

AEM version 6.4, Java version: jdk1.8.0_191.jdk

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1 回答 1

4

<Embed-Transitive>true</Embed-Transitive>所以我的猜测是正确的，尽管存在传递依赖项，但不包括在内。

在AEM上运行elasticsearch作为搜索引擎时，需要执行以下操作：

  • 我在 pom.xml 中添加了所有传递依赖项（版本在 parent/pom.xml 中定义）：

      <!-- Elasticsearch -->
      <dependency>
          <groupId>org.elasticsearch.client</groupId>
          <artifactId>elasticsearch-rest-high-level-client</artifactId>
      </dependency>
      <dependency>
          <groupId>org.elasticsearch.client</groupId>
          <artifactId>elasticsearch-rest-client</artifactId>
      </dependency>
      <dependency>
          <groupId>org.elasticsearch</groupId>
          <artifactId>elasticsearch</artifactId>
      </dependency>
      <dependency>
          <groupId>org.elasticsearch</groupId>
          <artifactId>elasticsearch-x-content</artifactId>
      </dependency>
      <dependency>
          <groupId>org.elasticsearch.plugin</groupId>
          <artifactId>rank-eval-client</artifactId>
      </dependency>
      <dependency>
          <groupId>org.apache.commons</groupId>
          <artifactId>commons-imaging</artifactId>
          <scope>test</scope>
      </dependency>
      <dependency>
          <groupId>org.elasticsearch.plugin</groupId>
          <artifactId>lang-mustache-client</artifactId>
      </dependency>
      <dependency>
          <groupId>org.apache.httpcomponents</groupId>
          <artifactId>httpasyncclient</artifactId>
      </dependency>

在maven-bundle-plugin中将所有第三方依赖项添加为 < Embed-Dependency >非常重要，如下所示：

    <plugin>
        <groupId>org.apache.felix</groupId>
        <artifactId>maven-bundle-plugin</artifactId>
        <extensions>true</extensions>
        <configuration>
            <instructions>
                <Embed-Dependency>org.apache.servicemix.bundles.solr-solrj, noggit,
                    elasticsearch-rest-high-level-client,
                    elasticsearch,
                    elasticsearch-rest-client,
                    elasticsearch-x-content,
                    elasticsearch-core,
                    rank-eval-client,
                    lang-mustache-client,
                    httpasyncclient;
                </Embed-Dependency>
                <Embed-Transitive>true</Embed-Transitive>
                <Embed-Directory>OSGI-INF/lib</Embed-Directory>
                <Export-Package>we.retail.core.model*</Export-Package>
                <Import-Package>
                    *;resolution:=optional
                </Import-Package>
                <Private-Package>
                    we.retail.core*
                </Private-Package>
                <Sling-Model-Packages>
                    we.retail.core.model
                </Sling-Model-Packages>
                <_fixupmessages>"Classes found in the wrong directory";is:=warning</_fixupmessages>
            </instructions>
        </configuration>
    </plugin>

需要注意的重要事项：

  • 所有第三方依赖项（OSGi 之外的）必须包含在“嵌入依赖项”中
  • "Embed-Transitive" 必须设置为 true 才能包含传递依赖项
  • "Import-Package" 必须包含"*;resolution:=optional" 以排除所有无法解析的依赖项，以便程序可以正常运行
  • 出于某种原因，在添加“elasticsearch”依赖项时编译时出现错误，这对该任务并不重要，所以我决定以这种方式忽略它：
<_fixupmessages>"Classes found in the wrong directory";is:=warning</_fixupmessages>

尽管具有挑战性，但我最终解决了它。Google上有很多类似或相同的问题，所以我希望这会对某人有所帮助。感谢所有试图提供帮助的人。

于 2019-10-21T16:56:57.300 回答