added exception handler

[ror6ax]

This addresses #15720

[ghost]

Test Failed.

If the failures are unrelated to your code, don't stress, a core developer will know these apart.
In the future, if possible, please branch off a passing commit to avoid false positives.
Refer to this link for build results: http://jenkins.saltstack.com/job/salt-pr-build/7909/

[thatch45]

@ror6ax this does not merge cleanly, I will take a look, if it is a simple fix I will open another pull request with the fix and link it here