Feature: use relative paths instead of absolute paths in error messages

[sallain]

Is your feature request related to a problem? Please describe.

When a user reviews an error message for a validation activity that failed, they are shown the absolute path of the problematic file or directory. The absolute path is long and much of it is meaningless to the average user; in talk-aloud testing, we found that they skipped right over it and were unable to identify which file or directory was causing the issue.

The absolute path is used in error messages in the following activities:

• Validate SIP structure
• Validate SIP file formats

On a related, but inverse, note, Verify SIP manifest seems to be already using relative paths, though actually it might be TOO short. For the sake of consistency, all paths should start at the top-level SIP directory.

Describe the solution you'd like

Using the relative path of the file, starting at the top-level directory of the SIP, should make the path more comprehensible to users.

Describe alternatives you've considered

Can't really think of any - we need to provide enough information that the file/directory is uniquely identifiable, but not too much. Hopefully this is the right balance.

Additional context

This is a child issue of #43

[sallain]

LGTM!

[sallain]

Whoops, I just noticed that the absolute path is also used in Validate SIP metadata:

[fiver-watson]

@DanielCosme @sallain I see that feedback was added to this, but i am not sure it was noticed, so I am leaving this comment and moving this card back to in progress, so that the additional absolute paths found during QA above can be addressed at some point.

[fiver-watson]

That error is now showing a relative path - thanks!