Start Workflow from Sharepoint Designer with REST call (Workflows 2013)

Question

The following REST call:

https://{server}/{site}/_api/SP.WorkflowServices.WorkflowInstanceService.Current/StartWorkflowOnListItemBySubscriptionId(subscriptionId='caa09cae-3955-4c26-bb7e-24b4a95294b0',itemId='1ff07e38-7847-4786-90fc-28bd3b2255c9')

Returns:

"Input string was not in a correct format."

Does anyone know where I have gone wrong in this?

Answer 1

Just an issue with the parameter type; the itemID needed to be the ID, not the GUID. Documentation here:

https://msdn.microsoft.com/en-us/library/dn683475(v=office.12).aspx

Answer 2

REST CALL, many of us knows there are sharing on how you could do that in CSOM, but honestly that is not a REST API. I have shared how you could start a workflow in sharepoint online on office 365 by calling the REST API at _vti_bin/client.svc/ProcessQuery, basically you will need to do HTTP Post at the end point twice, one to get the workflow subscription and the other to trigger the workflow instance to start, find it here https://community.nintex.com/community/tech-blog/blog/2017/01/18/stronger-together-nintex-workflow-cloud-office-365