User id in act_hi_attachment is always null

[sistemasmunicip]

Hello,
using Java api to add attachments to a Task, the field user_id_ in the act_hi_attachment is never set.
As for the Attachment java class, it doesn't have an user_id attribute either.
I was hoping to control the users that can read/delete an attachment usin the user id.
I tried with Authorization.authenticatedUser and IdentityLink but the field is alwas null.
I'm using PostgreSQL and Activiti 5.14
Is it possible to save - retrieve user id from act_hi_attachment?

Thanks in advance
Esteban

[frederikherema1]

If you're adding attachments using the API, make sure the logic that calls the API is managing the "current user" the engine uses.
This is done by setting a (internally thread-local) value using org.activiti.engine.impl.identity.Authentication:



try {
  Authentication.setAuthenticatedUserId("kermit");

  // Your code here
} finally {
  Authentication.setAuthenticatedUserId(null); 
}

You can perhaps add it to a shared base-class of your application (or a servlet-filter) to have this done transparently.

[sistemasmunicip]

Frederik, thanks for the answer.
I had tried with Authentication.setAuthenticatedUserId but the result is the same. (in the first post I wrote the class wrong - Authorization.authenticatedUser) Here, the code for a test that attachs a file but without user id
<code>
                // ActProcessEngine is a custom class that returns default process engine if exists, or creates a new one
  ProcessEngine processEngine = ActProcessEngine.getProcessEngine();
  Authentication.setAuthenticatedUserId("my.user");
 
  File f = new File("/home/Descargas/5577.pdf");
 
  TaskService ts = processEngine.getTaskService();
   
  try {
   ts.createAttachment("application/pdf", "42592", "42221", "pruebaUsuario.pdf", "prueba con authenticated user", new FileInputStream(f));
  } catch (FileNotFoundException e) {
   e.printStackTrace();
  }

  Authentication.setAuthenticatedUserId(null);
  processEngine.close();
</code>

thanks again. Greetings
Esteban

[balsarori]

AttachmentEntity doesn't have a userId property and USER_ID_ of ACT_HI_ATTACHMENT is not mapped in Attachment.xml to any property.

[frederikherema1]

Good point balsarori. The user who creates the attachment is stored in a "comment":


public void createAttachmentComment(String taskId, String processInstanceId, String attachmentName, boolean create) {
    if (isHistoryEnabled()) {
      String userId = Authentication.getAuthenticatedUserId();
      CommentEntity comment = new CommentEntity();
      comment.setUserId(userId);
      comment.setType(CommentEntity.TYPE_EVENT);
      comment.setTime(ClockUtil.getCurrentTime());
      comment.setTaskId(taskId);
      comment.setProcessInstanceId(processInstanceId);
      if(create) {
        comment.setAction(Event.ACTION_ADD_ATTACHMENT);
      } else {
        comment.setAction(Event.ACTION_DELETE_ATTACHMENT);
      }
      comment.setMessage(attachmentName);
      getSession(CommentEntityManager.class).insert(comment);
    }
  }


[sistemasmunicip]

I know the AttachmentEntity doesn't have a user_id_ property, but I was thinking I could query directly to the table in the worst case. I will try the comment and let you know.
Thanks for your answers.
Esteban

[sistemasmunicip]

Hello. here's an update:
I got it working by querying the TaskService via getProcessInstanceComments(processInstanceId) - once the task is completed the attachment is related to the process instance - and then matching with the taskId (will see what to do when a task has more than one attachment)

Maybe I'm approaching it the wrong way, but here's the scenario:
I have a user task that has a listener for the onComplete event. That listener generates a pdf and attachs it to the task. This task is a part of an administrative process and I want  only the user that generated the attachment to be able to delete it, or someone with admin permission only (it is not saved as a file but as a byte stream on the act_ge_bytearray table).
So, when I saw the user_id_ field on the attachment table I thought - problem solved.

As balsarori pointed out,  AttachmentEntity doesn't have a user_id_ property, but there's still the field on the table. The comment table obviously has no attachment_id field - that would be wrong, but saves "AddAttachment" as action_ , and the file name as message_ . I'm curious as to why I can't retrieve any of the 2 fields through the Comment class (no getAction() or getMessage() methods ) - I can use getFullMessage() but it's null.

In my opinion, it would be much easier to save the user_id to the act_hi_attachment table, but then again, is my approach wrong?

Thanks
Esteban

[frederikherema1]

Esteban,

Comments and Attachments are a bit of "entities on the side", not 100% critical to the BPMN behaviour (as opposed to tasks, identity-links, executions, …). So the comments and attachments are added to facilitate working around tasks.

However, when I see your requirements, I think a better solution would be to use a process-variable for this and make your services smart enough to allow users to modify/delete that specific variable.

[sistemasmunicip]

Frederik:
I understand your point, will try to work out the solution.
Any chance, in future versions, of user_id_ being inserted in act_hi_attachment?
Thanks
Esteban

[balsarori]

@Frederik

I also had a similar requirement. I solved it by adding a userId property to AttachmentEntity (getUserId method to Attachment interface) and mapped it to Attachment.xml.

If you are interested I can create a pull request for this.