Problems with custom work item handlers

[gsi]

Service tasks in general do not work for me on kie workbench. I have tried to follow the documentation but to no success. All tasks under Service Tasks in Kie workbench do not work and a similar issue is experienced with my custom work item handlers.

I can go as far as including service tasks and custom tasks in a business process and deploying the project. The problem starts when I try to start a process instance, I get this error:

Process Instances failed to start: [TestProject.test:3 - Log:3] -- Could not find work item handler for Log

The server log snippet is as follows:

========================================================================================================================================================

[org.jbpm.designer.web.preprocessing.impl.JbpmPreprocessingUnit] (default task-93) Successfully deleted file : .../jbpm-installer/wildfly-8.1.0.Final/standalone/tmp/vfs/temp/tempc014fddbc9e42a15/jbpm-console.war-3107a71416517166/org.kie.workbench.KIEWebapp/stencilsets/bpmn2.0jbpm/view/activity/workitems/Log.svg

2014-08-21 23:15:16,227 WARN  [org.jboss.solder.exception.control.log] (default task-122) No handlers found for exception java.lang.IllegalArgumentException: java.io.FileNotFoundException:.../jbpm-installer/wildfly-8.1.0.Final/standalone/tmp/vfs/temp/tempc014fddbc9e42a15/jbpm-console.war-3107a71416517166/org.kie.workbench.KIEWebapp/stencilsets/bpmn2.0jbpm/view/activity/workitems/Email.svg (No such file or directory)

2014-08-21 23:15:16,237 ERROR [io.undertow.request] (default task-122) UT005023: Exception handling request to /jbpm-console/stencilset//org.kie.workbench.KIEWebapp/stencilsets/bpmn2.0jbpm/bpmn2.0jbpm.json/view/activity/workitems/Email.svg: java.lang.IllegalArgumentException: java.io.FileNotFoundException: .../jbpm-installer/wildfly-8.1.0.Final/standalone/tmp/vfs/temp/tempc014fddbc9e42a15/jbpm-console.war-3107a71416517166/org.kie.workbench.KIEWebapp/stencilsets/bpmn2.0jbpm/view/activity/workitems/Email.svg (No such file or directory)

  at org.jbpm.designer.web.stencilset.impl.LocalStencilSetImpl.getResourceContents(LocalStencilSetImpl.java:46) [jbpm-designer-backend-6.1.0.Final.jar:6.1.0.Final]

  at org.jbpm.designer.web.stencilset.impl.StencilSetServiceServlet.doGet(StencilSetServiceServlet.java:119) [jbpm-designer-backend-6.1.0.Final.jar:6.1.0.Final]

  at javax.servlet.http.HttpServlet.service(HttpServlet.java:687) [jboss-servlet-api_3.1_spec-1.0.0.Final.jar:1.0.0.Final]

=====================================================================================================================================================

I started with version 6.0.1 and later Version 6.1 and I still experience the same problem. I suspect I am missing something.

These are the steps that I follow when using my own work item handlers:

1. I put the jar with my custom work item handlers inside the dependency/ folder found inside the jbpm-installation directory

2. Edit the conf/META-INF/CustomWorkItemHandlers.conf and include my own as follows:

    "MyWorkItemHandler" : org.myorganisation.handlers.MyWorkItemHandler()

3. Execute ant install.dependencies

4. Execute ant install.demo

5. Execute ant start.demo

6. In my Kie workbench project's work item definitions I include an entry as follows;

[

    "name" : "MyWorkItemHandler",

    "displayName" : "My Work Item Handler",

    "icon" : "defaultservicenodeicon.png"

  ]

"My Work Item Handler" task becomes available under service tasks and I can include it in a business process. Starting a new process instance gives the Could not find work item handler error.

What am I missing?

I am using Java 1.7.0_67 and Ant 1.9.3 on Ubuntu 14.04.

G

[salaboy21]

Hi George,

I think that the only thing that you are missing is :

"1. I put the jar with my custom work item handlers inside the dependency/ folder found inside the jbpm-installation directory"

It should be inside the web application/WEB-INF/lib directory. As explained here:

http://salaboy.com/2013/10/22/kie-wb-jbpm-console-ng-configurations/

Look also for your second point that you need to edit that file but inside the web app..

HTH

[gsi]

Hi Mauricio,

Thanks. Copying the files manually works. It is strange though as the procedure explained above also does copy the files to correct directories in the jbpm-console.war.

I also think there is a bug though as sometimes even the default service tasks (Log,Email, Web Service ...) throw the same error while I expect them to work out of the box. I will investigate the bug  and report it if found.

Thanks once again.

G

[gsi]

It works perfectly now. The root cause was that the web app was failing to resolve a class that implements one of my custom work item handlers.