Skip preview expiry when owner cannot be determined

[PVince81]

Description

In some scenarios, the owner of trashed files or versions cannot be determined, instead of failing hard, just skip expiration.
This is just a mitigation as we need a proper solution for trash/version
preview expiry.

Please note that this is just a mitigation and actual issue isn't fixed yet (see below) as we need to bigger changes in the preview code to accomodate for versions, see #33188

Related Issue

Mitigation for #32346 (version expiry) and https://github.com/owncloud/enterprise/issues/3067 (trash expiry).

Motivation and Context

Mitigate the issue and avoid stopping the process or crashing whenever expiry did not work.

How Has This Been Tested?

• manual test

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Technical debt
• Tests

Checklist:

• Code changes
• Unit tests added
• Acceptance tests added
• Documentation ticket raised:

Open tasks:

• Backport (if applicable set "backport-request" label and remove when the backport was done)

[codecov]

Codecov Report

Merging #34118 into master will decrease coverage by <.01%.
The diff coverage is 0%.

@@             Coverage Diff              @@
##             master   #34118      +/-   ##
============================================
- Coverage     64.76%   64.76%   -0.01%     
- Complexity    18345    18347       +2     
============================================
  Files          1198     1198              
  Lines         69450    69454       +4     
  Branches       1281     1281              
============================================
  Hits          44982    44982              
- Misses        24095    24099       +4     
  Partials        373      373

Flag	Coverage Δ	Complexity Δ
#javascript	53.09% <ø> (ø)	0 <ø> (ø)	⬇️
#phpunit	66.11% <0%> (-0.01%)	18347 <0> (+2)

Impacted Files	Coverage Δ	Complexity Δ
lib/private/Preview.php	78.73% <0%> (-0.67%)	170 <0> (+2)

---

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Δ = absolute <relative> (impact), ø = not affected, ? = missing data
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[codecov]

Codecov Report

Merging #34118 into master will decrease coverage by <.01%.
The diff coverage is 0%.

@@             Coverage Diff              @@
##             master   #34118      +/-   ##
============================================
- Coverage     64.76%   64.76%   -0.01%     
- Complexity    18345    18347       +2     
============================================
  Files          1198     1198              
  Lines         69450    69454       +4     
  Branches       1281     1281              
============================================
  Hits          44982    44982              
- Misses        24095    24099       +4     
  Partials        373      373

Flag	Coverage Δ	Complexity Δ
#javascript	53.09% <ø> (ø)	0 <ø> (ø)	⬇️
#phpunit	66.11% <0%> (-0.01%)	18347 <0> (+2)

Impacted Files	Coverage Δ	Complexity Δ
lib/private/Preview.php	78.73% <0%> (-0.67%)	170 <0> (+2)

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 1f7264a...3921212. Read the comment docs.

[tomneedham]

Nice - pretty sure I've seen logs on my own instance because of this.

[PVince81]

yes, also had some on my own instance...

I still need to manually test this to confirm it does work.

[PVince81]

Tested manually with the steps from and breakpoints: #32346 (comment)

The skipping code is run and version previews are still on-disk, as expected.

[VicDeo]

Looks good

[PVince81]

Test steps here: #32346 (comment)

Before the fix you'll see an exception in the log.
After the fix the exception is gone.

Since this is a mitigation the version previews will still be present on disk and won't be deleted until we have a proper fix.