I have a geoprocessing service accessed through a Web App Builder App that appends a parcel to a dataset. I have tried arcpy.AddMessage, print and returning a message through arcpy.SetParameterAsText() but I cannot get it to report that it is finished, or failed.
It is currently asynchronous, and I think that may be why it doesn't return anything, but if I set it to synchronous on the server it fails (SubmitJob error).
Using the ArcGIS Online Assistant I can view the JSON for the web app and I see a setting "isSynchronous": false however setting this to true doesn't fix it as it still tries to SubmitJob (rather than ExecuteTask?).
How can I set up a synchronous service for use in a web app built with the Web App Builder? And how can I return messages to the Web App?