Get Workflow TemplateID

On my custom display form for a list I want to create a link to the Start Workflow page of a specified workflow. Getting the URL is simple, open an item and select to start the desired workflow. Copy the resultant URL and use it on the custom page (after sanitising the Source parameter to make it generic or to add an XSL parameter).

However, one of the required URL parameters is the TemplateID of the workflow, which changes every time it is edited. This is an annoyance if you are in active development and the workflow is being updated regularly.

So what we ideally want is the ability to get the workflow TemplateID from code. Luckily for us, MOSS provides the GetTemplatesForItem method of the Workflow web service. I use Darren Johnstone's JavaScript API for SharePoint services. Darren didn't implement the Workflow web service so I had to create it myself (only implemented the GetTemplatesForItem method so far).

The GetTemplatesForItem method only takes one parameter, the full URL of an item, e.g. 'http://moss2007/sites/WorkflowTestSite/Shared Documents/doc1.docx'. If the item is in a list (and not a library), the ows_FileRef attribute of the item is required, e.g. 'http://moss2007/sites/WorkflowTestSite/Custom List/23_.000'.

The returned XML includes information about the workflows attached to the item. To get the templateID, we use a simple jQuery selector with the name of the workflow:

workflows = new SPAPI_Workflows(GetRootUrl());

wfitems = workflows.getTemplatesForItem("http://moss2007/sites/WorkflowTestSite/Custom List/23_.000");

$(wfitems.responseXML).find("WorkflowTemplate[Name=Name of Workflow] [nodeName=WorkflowTemplateIdSet]").attr("TemplateId")

Of course if all we are really wanting is the URL to get to the start workflow page, we could simply use:

$(wfitems.responseXML).find("WorkflowTemplate[Name=Name of Workflow]").attr("InstantiationUrl")