java - 如何使用 Java API 从 Pentaho 作业中获取错误？

Question

我正在使用以下代码执行一些 Pentaho 作业(不是我的，只是来自遗留应用程序。如果需要，我必须更改代码):

JobMeta jobMeta = new JobMeta(jobName, null);
Job job = new Job(null, jobMeta);
job.start();
job.waitUntilFinished();

if (job.getErrors() != 0) {
    logger.error("Error encountered!");
    throw new RuntimeException(getTrace(job.getStackTrace()));
}

//...

private String getTrace(StackTraceElement[] elements) {
    StringBuilder sb = new StringBuilder();
    for (StackTraceElement element : elements) {
        sb.append(element.toString());
    }
    return sb.toString();
}

一切似乎都很好，但是 if 语句返回 true 并且我收到了这样一个蹩脚的无意义消息:

2015-03-29 16:30:43,658 INFO  [com.foo.bar.component.ETLComponent] ERROR on job /home/path/to/pentaho/jobs/main_job.kjb
java.lang.RuntimeException:
        at com.foo.barpentaho.KettleService.executeJob(KettleService.java:48)  //my class
        at com.foo.bar.component.ETLComponent.process(ETLComponent.java:64)    //my class
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
        at java.lang.reflect.Method.invoke(Method.java:597)
        at org.mule.model.resolvers.AbstractEntryPointResolver.invokeMethod(AbstractEntryPointResolver.java:151)
        at org.mule.model.resolvers.ExplicitMethodEntryPointResolver.invoke(ExplicitMethodEntryPointResolver.java:93)
        at org.mule.model.resolvers.DefaultEntryPointResolverSet.invoke(DefaultEntryPointResolverSet.java:39)
        at org.mule.component.DefaultComponentLifecycleAdapter.invoke(DefaultComponentLifecycleAdapter.java:350)
        at org.mule.component.AbstractJavaComponent.invokeComponentInstance(AbstractJavaComponent.java:86)
        at org.mule.component.AbstractJavaComponent.doInvoke(AbstractJavaComponent.java:77)
        at org.mule.component.AbstractComponent.invokeInternal(AbstractComponent.java:126)
        at org.mule.component.AbstractComponent.access$000(AbstractComponent.java:61)
        at org.mule.component.AbstractComponent$1$1.process(AbstractComponent.java:242)
        at org.mule.processor.chain.DefaultMessageProcessorChain.doProcess(DefaultMessageProcessorChain.java:99)
        at org.mule.processor.chain.AbstractMessageProcessorChain.process(AbstractMessageProcessorChain.java:66)
        at org.mule.processor.chain.InterceptingChainLifecycleWrapper.doProcess(InterceptingChainLifecycleWrapper.java:56)
        at org.mule.processor.chain.AbstractMessageProcessorChain.process(AbstractMessageProcessorChain.java:66)
        at org.mule.processor.chain.InterceptingChainLifecycleWrapper.process(InterceptingChainLifecycleWrapper.java:87)
        at org.mule.component.AbstractComponent.process(AbstractComponent.java:160)
        at org.mule.processor.chain.DefaultMessageProcessorChain.doProcess(DefaultMessageProcessorChain.java:99)
        at org.mule.processor.chain.AbstractMessageProcessorChain.process(AbstractMessageProcessorChain.java:66)
        at org.mule.processor.AbstractInterceptingMessageProcessorBase.processNext(AbstractInterceptingMessageProcessorBase.java:105)
        at org.mule.interceptor.AbstractEnvelopeInterceptor.process(AbstractEnvelopeInterceptor.java:55)
        at org.mule.processor.AsyncInterceptingMessageProcessor.processNextTimed(AsyncInterceptingMessageProcessor.java:111)
        at org.mule.processor.AsyncInterceptingMessageProcessor$AsyncMessageProcessorWorker.doRun(AsyncInterceptingMessageProcessor.java:158)
        at org.mule.work.AbstractMuleEventWork.run(AbstractMuleEventWork.java:43)
        at org.mule.work.WorkerContext.run(WorkerContext.java:310)
        at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
        at java.lang.Thread.run(Thread.java:662)

在网上搜索，我从 Pentaho API 示例中找到了这段代码(使用 Pentaho 5，但思路保持不变):

String filename = "..."; //path for the job to execute
TransMeta transMeta = new TransMeta(filename);
Trans trans = new Trans(transMeta);

trans.execute(null); // You can pass arguments instead of null.
trans.waitUntilFinished();
if ( trans.getErrors() > 0 )
{
  throw new RuntimeException( "There were errors during transformation execution." );
}

所以我会再次收到一条无意义的消息。我已经搜索到 javadoc 并且没有有用的信息获取错误的结果。

如何从 Pentaho 作业执行的结果中获取正确的错误消息？

我正在使用 Pentaho 4.3。

Answer 1

CentralLogStore可用于从作业执行步骤中获取正确的错误消息。 我在 Custom Java Api 中出于相同目的使用以下代码:

    job.waitUntilFinished();
    if (job.getErrors() > 0) {
      Log4jBufferAppender appender = CentralLogStore.getAppender();
      appender.removeGeneralMessages();
      String logText = appender.getBuffer(job.getLogChannelId(), false).toString();
      CentralLogStore.discardLines(job.getLogChannelId(), false);
      throw new RuntimeException(logText);
    } 

错误信息如下:

Job-62001 Error in [Processes/SubProcesses/ETL Report Transformation Process.process/Get Record Count]
Running Get_Number_Of_Records Transformation occurred error.
caused by: org.pentaho.di.core.exception.KettleException: 
We failed to initialize at least one step.  Execution can not begin!
    at org.pentaho.di.trans.Trans.prepareExecution(Trans.java:823)
    ...

可以在 wiki 上找到更多详细信息 here .