[Boltdb-shipper] If S3 ListObjects returns the directory itself getDBNameFromObjectKey fails

[netdata-be]

Chubaofs returns the following:

$ s3cmd ls s3://loki/index/index_18641/
2021-01-14 08:46            0  s3://loki/index/index_18641/
2021-01-14 08:46         3952  s3://loki/index/index_18641/xxx-1610612684957170124-1610613044.gz
2021-01-14 09:01         2990  s3://loki/index/index_18641/xxx-1610612684957170124-1610613900.gz
2021-01-14 09:16         6552  s3://loki/index/index_18641/xxx-1610612684957170124-1610614800.gz
2021-01-14 09:31         9487  s3://loki/index/index_18641/xxx-1610612684957170124-1610615700.gz

So the directory itself is also returned, therefore we need to skip if the object ends with a /

[CLAassistant]

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1 out of 2 committers have signed the CLA.

✅ slim-bean
❌ Wouter D'Haeseleer

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[codecov-io]

Codecov Report

Merging #3173 (ea7f637) into master (322e4bc) will increase coverage by 0.00%.
The diff coverage is 66.66%.

@@           Coverage Diff           @@
##           master    #3173   +/-   ##
=======================================
  Coverage   63.25%   63.25%           
=======================================
  Files         188      188           
  Lines       16304    16316   +12     
=======================================
+ Hits        10313    10321    +8     
- Misses       5051     5055    +4     
  Partials      940      940           

Impacted Files	Coverage Δ
pkg/storage/stores/shipper/compactor/table.go	60.81% <0.00%> (-0.84%)	⬇️
pkg/storage/stores/shipper/downloads/table.go	65.57% <50.00%> (-0.26%)	⬇️
pkg/storage/stores/shipper/util/util.go	40.00% <100.00%> (+5.62%)	⬆️
pkg/canary/comparator/comparator.go	76.36% <0.00%> (-1.82%)	⬇️
pkg/logql/evaluator.go	90.23% <0.00%> (+0.35%)	⬆️
pkg/querier/queryrange/downstreamer.go	97.64% <0.00%> (+2.35%)	⬆️

[owen-d]

Thanks for this PR -- we definitely don't want this failing on a legitimate use case.

@sandeepsukhani Can you take a look? All looks functionally to me, but I think there might be a better way to validate these than checking the suffix in four places.

[sandeepsukhani]

Thanks for this PR -- we definitely don't want this failing on a legitimate use case.

@sandeepsukhani Can you take a look? All looks functionally to me, but I think there might be a better way to validate these than checking the suffix in four places.

I agree with Owen, we should move it to a common place. Maybe add a helper function which would accept a list of objects as inputs and return a list of objects after removing objects which end with a /. It makes future enhancement and writing tests easier.

[netdata-be]

Thanks for this PR -- we definitely don't want this failing on a legitimate use case.
@sandeepsukhani Can you take a look? All looks functionally to me, but I think there might be a better way to validate these than checking the suffix in four places.

I agree with Owen, we should move it to a common place. Maybe add a helper function which would accept a list of objects as inputs and return a list of objects after removing objects which end with a /. It makes future enhancement and writing tests easier.

Would you mind doing that for me? I'm not a hero in this ;-)

[slim-bean]

I create a separate issue with these changes #3394

After pushing code to address the reviews I realized the CLA wasn't signed (likely because the email on the original commit didn't match the email on the github account) and another change also introduced a merge conflict I decided to make a separate so I can get this merged today and it should make the next release.

Apologies @netdata-be, not trying to take any credit away from your finding and fixing this issue, I hope you understand!