ci(instrumentation-http): improve metrics test stability

[pichlermarc]

Which problem is this PR solving?

Currently the tests for metrics in the @opentelemetry/http-instrumentation package are failing every once in a while. This PR aims to improve test stability by introducing a custom MetricReader with a export method that does not rely on time passed.

Fixes #3238

Type of change

• Bug fix (non-breaking change which fixes an issue)

How Has This Been Tested?

• Existing unit tests

Checklist:

• Followed the style guidelines of this project
• Unit tests have been added
• Documentation has been updated

[codecov]

Codecov Report

Merging #3242 (5ef3a6f) into main (bd0a77f) will decrease coverage by 0.01%.
The diff coverage is n/a.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3242      +/-   ##
==========================================
- Coverage   93.30%   93.29%   -0.02%     
==========================================
  Files         203      203              
  Lines        6606     6606              
  Branches     1389     1389              
==========================================
- Hits         6164     6163       -1     
- Misses        442      443       +1     

Impacted Files	Coverage Δ
...-trace-base/src/platform/node/RandomIdGenerator.ts	87.50% <0.00%> (-6.25%)	⬇️

[dyladan]

I think the changes in #3225 broke this PR and now you have to use the override modifier on the testing class methods

[legendecas]

I'm in favor of this explicit collection than the periodic metric reader based approach!

[legendecas]

CI is complaining but the code LGTM.

[osherv]

Hey! That's an awesome feature!
Actually, that could be really useful in the 'contrib' package also (thanks @legendecas for pointing that out).
Does it possible to export this TestMetricReader so we can use it in the contrib repo? We already exporting InMemoryExporters that are really help :) Otherwise, we'll implement that also in the contrib package.
Here's the related contrib pr
Thanks!

[pichlermarc]

I think the changes in #3225 broke this PR and now you have to use the override modifier on the testing class methods

Yep that's the problem. Fixed in 36eb96b 🙂

[pichlermarc]

Hey! That's an awesome feature! Actually, that could be really useful in the 'contrib' package also (thanks @legendecas for pointing that out). Does it possible to export this TestMetricReader so we can use it in the contrib repo? We already exporting InMemoryExporters that are really help :) Otherwise, we'll implement that also in the contrib package. Here's the related contrib pr Thanks!

Hi, thanks! 🙂 While I do agree that this is quite useful for tests, there are no plans to export this right now (see this comment here).
For now I would recommend to copy this over to the contrib repo, but be aware that it might not work 1:1 as there are unreleased changes to the MetricReader at the moment.

[osherv]

@pichlermarc Thanks :)