Stack traces are currently shown by default in GBNG. There is a comment in GradebookNgApplication.java that implies this behaviour can be changed:
However, flipping this value has no effect because ErrorPage.java does not check which value is being used, and dumps the stacktrace into a Wicket label regardless (it also has a comment that this should be configurable "at some point"):
This PR proposes the following changes:
- make the default value correspond to the sakai.property "portal.error.showdetails"
- make ErrorPage.java determine which value is being used, and display the stack trace as appropriate (but admins should always see the stack trace)