[epic] Excessive number of 500 errors

[fao89]

Author: wibbit (wibbit)

Redmine Issue: 8359, https://pulp.plan.io/issues/8359

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Morning all.

Had an issue late last week, where I was trying to create the same repository twice in two different threads (separate issue, of course, which I have addressed).

However, as part of that work, it proved surprisingly difficult to track down, and the only lead I had was a generic Server 500 error, and tracing through the logs on the Pulp3 server to work out why.

In this instance at least, it would have been useful to have a more specific error that I could program around to state that the requested repository was already present.

FYI, there has been a similar discussion in https://pulp.plan.io/issues/7114 where uploading an artifact, results at least in a usable (if not great) error, that I can then use to code around.