Trigger a workflow using a custom menu item

Hi Community,

We have a requirement that should call a particular workflow model when a user clicks on a custom menu item (Say Publish xyz report).

My queries are around the following areas:
1) What would be the best approach to call the said workflow from the menu item? (Like : Should i write a JSP or a servlet that would internally do the workflow calling logic?)
2) Has anyone done such an implementation? I have read the forums on WFM initiation using CSSDK but havent found a similar situation to mine.

It would be really helpful if a reference to any documentation or code snippet to instantiate such a workflow.

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ISCBorisB

Hi Community,

We have a requirement that should call a particular workflow model when a user clicks on a custom menu item (Say Publish xyz report).

My queries are around the following areas:
1) What would be the best approach to call the said workflow from the menu item? (Like : Should i write a JSP or a servlet that would internally do the workflow calling logic?)
2) Has anyone done such an implementation? I have read the forums on WFM initiation using CSSDK but havent found a similar situation to mine.

It would be really helpful if a reference to any documentation or code snippet to instantiate such a workflow.

That's an interesting question...

It is trivial to do with WFT, using Workflow CC URL Command "newjob" with "iw_template_file" Parameter.
Does anybody know what are the newjob's parameters to indicate a Model? Do such parameters even exist?

Rick Poulin

Does anybody know what are the newjob's parameters to indicate a Model? Do such parameters even exist?

Don't know, but I've successfully launched workflow models from the CSSDK. One could just wrap their own screen around that, but that bypasses the 'normal' instantiation screen which may or may not be the intent of the OP.

@bmazum: if you would clarify what exactly you're looking for in terms of functionality, then we can recommend an approach. Your query is too general to recommend one way versus another.

Migrateduser

Sure Rick! What i need to do is:

1) Call a servlet from a custom menu item (Done)
2) This servlet does some processing and dispatches the request to a jsp (Done)
3) The said jsp would require some input from the user and then, move ahead to a servlet/jsp that would invoke a workflow. (This is what i need to do)

Step 3 mentioned above would contain some code like:


CSClient client = (CSClient) request.getAttribute("iw.csclient");
CSWorkflowEngine wfEngine = client.getWorkflowEngine();
CSWorkflow csWorkflow = wfEngine.createWorkflow("I_DO_NOT_KNOW_WHAT_GOES_HERE");

I came across a discussion devnet (http://devnet.interwoven.com/forums_vb/showthread.php?t=36690) that recommends using the job specification file here. Its just that i am not sure what is the best way to invoke the workflow...if there is one that you say you are aware of, please share it with the forum.

ISCBorisB

Don't know, but I've successfully launched workflow models from the CSSDK

That was not my question. I have no problem coding within TS Content Services framework.

That said, for WFT I do not have to code anything at all to provide specific WF instantiation Link,
be it Custom menu item, DCT Button or a URL supplied through some Mail. So I was hoping that
TS Development ported CC "newjob" Command to newer WFM as well. Fat chance, I know but still...

Migrateduser

Hi Community, I went by the suggested approach in a few posts on devnet and got hold of the WFM specification file using Debug mode.

Then, I read this spec file (an xml) using file readers, inject dependencies if any and kick off the workflow. It looks fine till now.

However, if my workflow has a user interactive task, like approve/review/resolve errors etc, is there a way to get the screen to pop up in front of the user? I know it sounds like a far fetched idea but, if anyone has faced this issue, i would not want to reinvent the wheel!

Adam Stoller

However, if my workflow has a user interactive task, like approve/review/resolve errors etc, is there a way to get the screen to pop up in front of the user? I know it sounds like a far fetched idea but, if anyone has faced this issue, i would not want to reinvent the wheel!

There are only a few scenarios in which a CGI task will start automatically, and these are documented in the manuals and numerous threads here.
For any other scenario / interactive task, you would need a task to send email to the user prior to the task with which they need to interact, in order to facilitate a [sort-of] "pop up in front of the user" action.

Migrateduser

Thank you ghoti. That information is quite helpful!

Migrateduser

Hi Community,

I would like to share my findings on this topic. I have shared them in the form of Q&A below for the benifit of those who might find it useful. I would also request the experts to correct me in case i have gone wrong anywhere.

Question 1 : Can i instantiate a wfm workflow using CSSDK?
Answer 1 : Yes you can. But unlike WFT, you do not have a useful command that instantiates a workflow from wft file (Please read about iwwft_instantiator.cgi and iwwft_compile.ipl in the WFT Developers Guide). You do have iwmodelc under iw-home/bin to instantiate a workflow model from command line but i cannot pass any parameters to it.

Question 2 : So what do i do?
Answer 2: Please use iwmodelc clt if you do not need parameters to kick off your workflow. If you do need parameters, you could write some Java code to kickstart your workflow. you need to do the following:
2.1-> Edit available_models.xml at TS location /iwadmin/main/workflowModels/WORKAREA/iw-wa/Internal
2.2-> Select debug=true for the model you wish to instantiate. Save the file and submit it.
2.3->Start your workflow and choose Debug mode in it. Once you go ahead, you will be presented with 2 xmls. Copy the one in Green. This is your workflow specification xml file. Save it as a file say workflowmodel.xml(A workflow specification xml file is something that is passed on to the workflow engine after it gets instantiated.)

Question 3 :How do i use workflowmodel.xml file in my java code?
Answer 3 : Please save this file at a convenient location on Teamsite Server. You can write a servlet within content_center web app and use CSSDK in it to start your workflow. Sample code shared below;


// get the cs client
CSClient client = (CSClient) request.getAttribute("iw.csclient");

//get the xml file data as a String
String fileData="Empty String";
 try {
  File systemFile = new File(ENTER THE PATH TO workflowspecification.xml HERE);
  FileReader fileReader = new FileReader(systemFile);
  BufferedReader bufferedReader = new BufferedReader(fileReader);
  String line = null;
  fileData = "";
  while ((line = bufferedReader.readLine()) != null) {
   fileData = fileData + line;
  }
 } catch (IOException e) {

  e.printStackTrace();
 }

//Get the workflow engine from CSClient
CSWorkflowEngine wfEngine = client.getWorkflowEngine();

//Now fetch the workflow from the workflow engine using fileData string as input to its createWorkflow method
  try {
   CSWorkflow csWorkflow = wfEngine.createWorkflow(fileData);
   out.println("Instantiated Workflow : "+csWorkflow.getName()+" with id="+csWorkflow.getId());
  } catch (CSAuthorizationException e) {
   out.println("CSAuthorizationException occured. Error code is : "
     + e.getErrorCode());
   e.printStackTrace();
  } catch (CSRemoteException e) {
   out.println("CSRemoteException occured. Error code is : "
     + e.getErrorCode());
   e.printStackTrace();
  } catch (CSExpiredSessionException e) {
   out.println("CSExpiredSessionException occured. Error code is : "
     + e.getErrorCode());
   e.printStackTrace();
  } catch (CSException e) {
   out.println("CSException occured. Error code is : "
     + e.getErrorCode());
   e.printStackTrace();
  }

This will get your workflow started. But please note that if your workflow has any user interactive task, it will not automatically pop up in front of you. You will have to go to the workflow tab and start the next task yourself. Or you have to fetch the latest Task id and use it in a request dispatcher to send you to a URL Command like:

http:///iw-cc/command/iw.ccpro.task_details?taskid=ENTER_TASK_ID_HERE

.
I have not tried this.

Question 4: Why have i not tried the iw.ccpro.task_details URL command?
Answer 4: I did some tweaking of the new job screen. It shows me a bunch of available workflows. Using a view source of the html, i cooked up a link which goes something like:

http:///iw-cc/command/iw.ccpro.new_job?workflow_command=new_job&iw_template_file=IPM_FILE_NAME&iw_template_name=WHAT NAME YOU WANT TO SHOW ON THE TITLE&full_redirect=true&workflowType.flag=true&cwd.vpath=VPATH FROM WHERE THIS WORKFLOW WILL GET KICKED OFF

Please validate if this is a good way to end the iwmodelc nightmare. I will keep the parameters in a form with hidden variables. I am showing the GET form of it so that its readable...

COMMENTS INVITED.

ISCBorisB

2.3->Start your workflow and choose Debug mode in it. Once you go ahead, you will be
presented with 2 xmls. Copy the one in Green. This is your workflow specification xml file. Save
it as a file say workflowmodel.xml...

Personally, Entry #2.3 (see above) is perhaps the one I liked least in this post.

It will work as long as pre-canned "one size fits all" WF Specs is all you need. More dynamic approach may
call for generating WF Specs within your code. You can do that for example by running iwmodelc with
"-d" flag and "outputFolder" parameter.

It would be even better if CSSDK provides an API to evaluate Models into Specs. Does anybody know if TS
exposes this functionality? (Just like with my previous carping, evaluating WFT into Job Specs was trivial - sigh...)

Once again, just my opinion.

Migrateduser

Don't know, but I've successfully launched workflow models from the CSSDK. One could just wrap their own screen around that, but that bypasses the 'normal' instantiation screen which may or may not be the intent of the OP.

@bmazum: if you would clarify what exactly you're looking for in terms of functionality, then we can recommend an approach. Your query is too general to recommend one way versus another.

Hi Rick,

I need some insight into how you have wrapped your own screen to bypass the normal instantiation screen. Could you help?

Rick Poulin

I think you've already figured out most of it. My scenario went like this:

* User gets a link (in an email / custom menu option / other screen / etc)
* Link goes to a custom JSP, which is essentially my own "instantiation screen"
* User fills out the fields and hits 'go'
* Servlet receives the form post and calls iwmodelc with -i flag
* The very important magic is that the first task in my workflow is an external task owned by SYSTEM/iwui where command is something that equates to a noop (e.g. 'echo')
* iwmodelc will have returned a job ID. I can use this with the CSSDK to find the job and its active task, which is my "dummy" external task
* Since the workflow is effectively "paused", I can update things like task variables, group task owners, etc. When I'm done, I callback the external task and the workflow gets started for real.
* For bonus points, look at the task that follows my dummy external task. If that task is a CGI task and owner = $IW_USER and immediate=true, then the result of the original form post is a HTTP302 redirect to transition_task where task ID is the ID of the CGI task. (Look up URL Commands in the UI customization guide).

As you mentioned, you can't pass params to iwmodelc, so configurable WFM variables won't work. If the actual model needs to change (i.e. would normally have conditional links), fire off iwmodelc in debug mode, which will produce the jobspec dynamically (safer / more flexible than generating it yourself once and storing it). You can then manipulate the jobspec as necessary before feeding it to CSWorkflowEngine.createWorkflow().

One last note.. The only supported way of using the iwmodelc function is to fork a Process object to the command line tool. However, if you crack it open, you'll see that it's just a shell script that instantiates a JVM call. For performance/efficiency, I've built mine in such a way that I call the same class (com.interwoven.modeler.clt.IWModelsC) within the same JVM that is running my JSP/Servlet. It's not really supported, in that it might require adjustments after upgrades, but it's much much more efficient than forking *two* new processes.

Migrateduser

I think you've already figured out most of it. My scenario went like this:

* User gets a link (in an email / custom menu option / other screen / etc)
* Link goes to a custom JSP, which is essentially my own "instantiation screen"
* User fills out the fields and hits 'go'
* Servlet receives the form post and calls iwmodelc with -i flag
* The very important magic is that the first task in my workflow is an external task owned by SYSTEM/iwui where command is something that equates to a noop (e.g. 'echo')
* iwmodelc will have returned a job ID. I can use this with the CSSDK to find the job and its active task, which is my "dummy" external task
* Since the workflow is effectively "paused", I can update things like task variables, group task owners, etc. When I'm done, I callback the external task and the workflow gets started for real.
* For bonus points, look at the task that follows my dummy external task. If that task is a CGI task and owner = $IW_USER and immediate=true, then the result of the original form post is a HTTP302 redirect to transition_task where task ID is the ID of the CGI task. (Look up URL Commands in the UI customization guide).

As you mentioned, you can't pass params to iwmodelc, so configurable WFM variables won't work. If the actual model needs to change (i.e. would normally have conditional links), fire off iwmodelc in debug mode, which will produce the jobspec dynamically (safer / more flexible than generating it yourself once and storing it). You can then manipulate the jobspec as necessary before feeding it to CSWorkflowEngine.createWorkflow().

One last note.. The only supported way of using the iwmodelc function is to fork a Process object to the command line tool. However, if you crack it open, you'll see that it's just a shell script that instantiates a JVM call. For performance/efficiency, I've built mine in such a way that I call the same class (com.interwoven.modeler.clt.IWModelsC) within the same JVM that is running my JSP/Servlet. It's not really supported, in that it might require adjustments after upgrades, but it's much much more efficient than forking *two* new processes.

Hi!

Thank you for your inputs! What i did was inspecting the html of the new job screen and getting hold of the form that triggers the workflow. I submitted that form from a custom jsp and was able to see the first user interactive task in the workflow. Please provide your comments on this approach if any?

Rick Poulin

Please provide your comments on this approach if any?

Well, it's simple and (presumably) works for your current use case, so there's that.

My main concerns would be that
1) it's an unsupported hack, so it may break when you upgrade and you might not be around to fix it (so document the code and your reasons thoroughly for the next person); and
2) it may not be flexible enough for future needs, so you may be just delaying the effort of building a more extensive customization

But as long as you (and your client) understand that and are comfortable with it, then there's not much else to say.

Migrateduser

Well, it's simple and (presumably) works for your current use case, so there's that.

My main concerns would be that
1) it's an unsupported hack, so it may break when you upgrade and you might not be around to fix it (so document the code and your reasons thoroughly for the next person); and
2) it may not be flexible enough for future needs, so you may be just delaying the effort of building a more extensive customization

But as long as you (and your client) understand that and are comfortable with it, then there's not much else to say.

Thanks rick. I was of the same opinion. These points are noted.