topic Re: Variables Array Always Empty in REST 'Start a Process Instance' Resource Results in Alfresco Archive

Variables Array Always Empty in REST 'Start a Process Instance' Resource Results

ryanj1 — Wed, 02 Apr 2014 21:30:31 GMT

First, I'm using Activiti 5.15. (If this has been fixed in V5.15.1, let me know; my understanding is that version is exclusively for the MySQL 5.6 bug.)When calling the "Start a Process Instance" REST resource, I noticed that the "variables" array was always empty, regardless of whether a process in

Re: Variables Array Always Empty in REST 'Start a Process Instance' Resource Results

trademak — Mon, 07 Apr 2014 09:25:22 GMT

Hi Ryan,

Good to see you back on the forum 😉
Variables are not returned when creating a process instance, similar to how it works in the Java API.
The variables list is only filled when you query on process instances with the includeVariables option.
To get the variables an additional REST call is required.

Best regards,

Re: Variables Array Always Empty in REST 'Start a Process Instance' Resource Results

ryanj1 — Mon, 07 Apr 2014 15:09:54 GMT

And I'm happy to be back.

If I'm understanding you correctly, you're basically saying that the product - in its out-of-the-box configuration - currently doesn't provide the ability to initiate a process and retrieve the current values of all variables when the process enters a wait state. Of course, that is consistent with the manner in which most (or all) BPM tools are currently designed and implemented. With that said, the pattern I'm describing is a legitimate pattern that customers may need their BPM tools to support. (In fact, one of the issues I encountered on a recent consulting engagement - where the customer was looking to select a BPM tool - was that none of the tools supported that pattern.) As a result, my thought is that it might be nice for Activiti to add a REST resource that would provide that ability.

Of course, I'd be willing to contribute that simple addition to the project if you agree that it would be helpful.

Re: Variables Array Always Empty in REST 'Start a Process Instance' Resource Results

trademak — Tue, 08 Apr 2014 13:29:08 GMT

Hi Ryan,

Yes that's correct. I can understand that it's sometimes helpful to get back the variables directly in the response. If you are willing to add an option to the existing "create process instance" REST service that would be great.

Thanks,

Re: Variables Array Always Empty in REST 'Start a Process Instance' Resource Results

ryanj1 — Tue, 22 Apr 2014 05:13:44 GMT

Tijs,

Sorry for the delayed response. My current client - actually an Activiti client - has had me working hard over the past couple of weeks. (It's been fun, though.)

I'd be happy to add an option to the existing "create process instance" REST service. To do so, I would have to modify three source files:

1) org.activiti.rest.service.api.runtime.process.ProcessInstanceCreateRequest (I would need to add the additional boolean variable here to indicate whether to return variables.)
2) org.activiti.rest.service.api.runtime.process.ProcessInstanceResponse (This isn't technically required for this change, but a nice, complementary feature is a flag in the output noting whether the process instance has been completed or not. That would be added herein.)
3) org.activiti.rest.service.api.RestResponseFactory (This is where the bulk of the code would be. I would use the code cited earlier within this thread.)

I assume you would want me to use the code for Activiti 5.15.1 to make these changes? (Though I suspect that none of these were changed from 5.15 to 5.15.1.) Let me know, and also let me know what timing constraints you have for the next release. Note that it shouldn't take me long to make these changes, primarily because I have all but the changes to ProcessInstanceCreateRequest already made (and tested) on my own instance.

Re: Variables Array Always Empty in REST 'Start a Process Instance' Resource Results

frederikherema1 — Tue, 22 Apr 2014 08:22:04 GMT

Ryan,

Maybe good to have a pull-request for this, so we can take a better look at the suggested solution. I'm quite sure nothing changed in the code related to this feature. Including process-variables with a process-instance response is something that seems to be a common usecase, judging from the forum, so exposing this on the normal GET of a single instance whould also make sense (instead of only allowing this in the GET on the collection, as currently implemented).

Re: Variables Array Always Empty in REST 'Start a Process Instance' Resource Results

ryanj1 — Tue, 22 Apr 2014 13:43:24 GMT

Sounds like a plan. I'd be happy to just send along the code via email too if you'd like to have a look at it that way. And of course, if you have another recommendation on how to retrieve the variables that might be more efficient, I'd be happy to hear it.

Re: Variables Array Always Empty in REST 'Start a Process Instance' Resource Results

jbarrez — Thu, 24 Apr 2014 07:23:17 GMT

> Sounds like a plan. I'd be happy to just send along the code via email too if you'd like to have a look at it that way

Pull requests are easiest. Patches, emails also work 😉
Looking forward to it.

No changes in that area in the latest releases, so your explanation above should work.

Re: Variables Array Always Empty in REST 'Start a Process Instance' Resource Results

ryanj1 — Wed, 07 May 2014 19:56:53 GMT

I've created a pull request for my proposed modifications. Per Tijs comment earlier in this post, I added a flag ("returnVariables") that can be submitted in the request JSON to the POST runtime/process-instances endpoint to indicate whether variables should be returned or not. If it isn't specified or if it's set to false, the endpoint behaves in exactly the same manner as it does in Activiti today. Thus, this change shouldn't cause any issues for users who upgrade to a release in which these changes included and who use the endpoint in their environments today.

By the way, this is my first GitHub pull request, so if I messed something up, please let me know…

-Ryan

Re: Variables Array Always Empty in REST 'Start a Process Instance' Resource Results

ssun — Thu, 29 May 2014 00:17:56 GMT

Did not see this before my posts on the other thread. http://forums.activiti.org/content/list-process-instances-rest-returns-empty-processvariables

So what said on the other thread about this already pulled into master and fixed in next version of 5.13 is not correct?

–Gordon

Re: Variables Array Always Empty in REST 'Start a Process Instance' Resource Results

ssun — Thu, 29 May 2014 01:15:51 GMT

I take back my previous post. I added includeProcessVariables=true worked, I mistakenly added includeVariables
This post is about the return when create a process instance using.

Re: Variables Array Always Empty in REST 'Start a Process Instance' Resource Results

ryanj1 — Sat, 14 Jun 2014 17:32:06 GMT

I'm glad it worked! If you need further assistance, please don't hesitate to reach out, and good luck with Activiti.

Re: Variables Array Always Empty in REST 'Start a Process Instance' Resource Results

atifelkhachine — Thu, 24 Jul 2014 03:02:35 GMT

Hi, this has not worked for me.
Is this future already included in 5.15.1 ?

Best Regards,
Atif

Re: Variables Array Always Empty in REST 'Start a Process Instance' Resource Results

atifelkhachine — Fri, 25 Jul 2014 03:48:34 GMT

I have tried this url :
http://kermit:kermit@localhost:8080/activiti-webapp-rest/service/runtime/process-instances?includeProcessVariables=true

but i'am always getting an empty variables array : <variables/>
One more thing, is that i got an XML response instead of json, even with the header : Content-Type application/json.

This test was done on 2.5.17 version.

With kind regards,
A.ELK

Re: Variables Array Always Empty in REST 'Start a Process Instance' Resource Results

frederikherema1 — Fri, 25 Jul 2014 07:49:17 GMT

What version did you test it against? Are you sure the variables are set on process-instance level, not on a child-execution?

Re: Variables Array Always Empty in REST 'Start a Process Instance' Resource Results

atifelkhachine — Fri, 25 Jul 2014 13:18:09 GMT

I have tested against 5.17.
I have a process with start -> Script Task -> End
Script Task : i do execution.setVariable("myVar","toto");

I am wondering if it's the correct way to do the setVariable.

Best regards,
AELK

Re: Variables Array Always Empty in REST 'Start a Process Instance' Resource Results

sahusunil — Fri, 25 Jul 2014 15:00:27 GMT

I have tried and it's working fine if you list down all process instances. I do see variables as shown below. The only question I have, Can we get variable info for particular process-instance? It works fine with list but if I try with particular process-instance, variables array is coming blank.

http://localhost:8080/activiti-rest/service/runtime/process-instances?includeProcessVariables=true - Works fine

http://localhost:8080/activiti-rest/service/runtime/process-instances/8096?includeProcessVariables=true - Gives blank variables array

{
           "id": "8096",
           "url": "http://localhost:8080/activiti-rest/service/runtime/process-instances/8096",
           "businessKey": null,
           "suspended": false,
           "processDefinitionId": null,
           "processDefinitionUrl": "http://localhost:8080/activiti-rest/service/repository/process-definitions/null",
           "activityId": "usertask2",
           "variables":
           [
               {
                   "name": "question",
                   "type": "string",
                   "value": "Y",
                   "scope": "local"
               }
           ],
           "tenantId": ""
       }

Re: Variables Array Always Empty in REST 'Start a Process Instance' Resource Results

atifelkhachine — Fri, 25 Jul 2014 17:30:13 GMT

I can't understand why not worked for me 😕
i did an HTTP POST on : http://kermit:kermit@localhost:8080/activiti-webapp-rest/service/runtime/process-instances?includeProcessVariables=true

The request body is like :
{
"processDefinitionId":"process:1:101"
}
The response is :
<code>
<ProcessInstanceResponse>
<id>2592</id>
<url>
http://localhost:8080/activiti-webapp-rest/service/runtime/process-instances/2592
</url>
<businessKey/>
<suspended>false</suspended>
<ended>true</ended>
<processDefinitionId>process:1:101</processDefinitionId>
<processDefinitionUrl>
http://localhost:8080/activiti-webapp-rest/service/repository/process-definitions/process%3A1%3A101
</processDefinitionUrl>
<activityId>endStep</activityId>
<variables/>
<tenantId/>
<completed>true</completed>
</ProcessInstanceResponse>
</code>

——————
The script task code :
<code><scriptTask id="scriptTask" name="script task" scriptFormat="groovy">
<script>execution.setVariable("myVar", "TotoTiti");</script>
</scriptTask></code>

Re: Variables Array Always Empty in REST 'Start a Process Instance' Resource Results

sahusunil — Tue, 29 Jul 2014 04:14:25 GMT

Can you add activiti:autoStoreVariables="true" in your scriptTask and try it again?

Thanks

Re: Variables Array Always Empty in REST 'Start a Process Instance' Resource Results

atifelkhachine — Tue, 29 Jul 2014 18:06:55 GMT

Hi, thank you for your reply.
Unfortunetly i have already tried this and got an empty variables array :
<code>
<process id="process" isExecutable="true">
<startEvent id="startStep" name="start step" activiti:initiator="kermit"/>
<sequenceFlow id="sid-201DAF9E-D12E-498C-8D7D-3EB68159D961" sourceRef="startStep" targetRef="scriptTask"/>
<scriptTask id="scriptTask" name="script task" scriptFormat="groovy" activiti:autoStoreVariables="true">
<script>execution.setVariable("myVar", "TotoTiti");</script>
</scriptTask>
<endEvent id="endStep" name="END STEP"/>
<sequenceFlow id="sid-F0548EB1-51AE-419D-9F90-52CBAC2B722B" sourceRef="scriptTask" targetRef="endStep"/>
</process>
</code>