Kill process instance when running in an infinite loop without wait state

Camunda 7 Topics Discussion & Questions
6

Hi,

Just to provide some basic understanding: Camunda does not compile a BPMN model or generates code. It interprets the model.

Regarding your actual question, it should be fairly easy to build such a timeout facility yourself and plug it into the engine:

Write a command interceptor that keeps track of the time:

package org.camunda.bpm.unittest;

import org.camunda.bpm.engine.impl.interceptor.Command;
import org.camunda.bpm.engine.impl.interceptor.CommandInterceptor;

public class TimeoutInterceptor extends CommandInterceptor {

  protected static final long TIMEOUT_MILLIS = 5 * 60 * 1000;
  protected static ThreadLocal<Long> commandBeginTime = new ThreadLocal<Long>();

  public <T> T execute(Command<T> cmd) {

    boolean recordTime = commandBeginTime.get() == null;
    if (recordTime) {
      commandBeginTime.set(System.currentTimeMillis());
    }

    try {
      return next.execute(cmd);
    } finally {
      if (recordTime) {
        commandBeginTime.set(null);
      }
    }
  }

  public static void ensureThreadNotTimedOut() {
    long currentTimeMillis = System.currentTimeMillis();
    long startTime = commandBeginTime.get();

    if (currentTimeMillis - startTime > TIMEOUT_MILLIS) {
      throw new RuntimeException("timeout");
    }
  }
}

Register the interceptor with the engine:

package org.camunda.bpm.unittest;

import java.util.Arrays;

import org.camunda.bpm.engine.ProcessEngine;
import org.camunda.bpm.engine.impl.cfg.ProcessEngineConfigurationImpl;
import org.camunda.bpm.engine.impl.cfg.ProcessEnginePlugin;
import org.camunda.bpm.engine.impl.interceptor.CommandInterceptor;

public class TimeoutPlugin implements ProcessEnginePlugin {

  public void postInit(ProcessEngineConfigurationImpl config) {
  }

  public void postProcessEngineBuild(ProcessEngine config) {
  }

  public void preInit(ProcessEngineConfigurationImpl config) {
    TimeoutInterceptor timeoutInterceptor = new TimeoutInterceptor();
    config.setCustomPreCommandInterceptorsTxRequired(Arrays.<CommandInterceptor>asList(timeoutInterceptor));
    config.setCustomPreCommandInterceptorsTxRequiresNew(Arrays.<CommandInterceptor>asList(timeoutInterceptor));
  }
}

Then use TimeoutInterceptor#ensureThreadNotTimedOut from any code that is called by the process engine as you like.

Cheers,
Thorben

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