gw-api: Support multiple RequestMirror filters per rule in GW API

[LiorLieberman]

Adding support for multiple RequestMirror filters per rule in GW API. both GRPC and HTTP

Fixes: #4566

ref: kubernetes-sigs/gateway-api#2199

[github-actions]

Hi @LiorLieberman! Welcome to our community and thank you for opening your first Pull Request. Someone will review it soon. Thank you for committing to making Contour better. You can also join us on our mailing list and in our channel in the Kubernetes Slack Workspace

[sunjayBhatia]

so far looks good, just one question 👍🏽

[LiorLieberman]

@skriss do you have any feedback before I go ahead and add tests for it?

[LiorLieberman]

I am not sure I followed all needed. I added the changelog now.
Let me know if something is missing

[sunjayBhatia]

looks like a minor lint issue to fix (can remove the offending comment?)

couple other comments to clean up:

• contour/internal/dag/status_test.go

  Line 7771 in dfe042e

  // Invalid filters still result in an attached route.

• contour/internal/dag/status_test.go

  Line 10526 in dfe042e

  // Invalid filters still result in an attached route.

and one to modify according to the new guidance on mirror policy:

• contour/internal/dag/gatewayapi_processor.go

  Lines 1132 to 1135 in dfe042e

  	// Per Gateway API docs: "Specifying a core filter multiple times
  	// has unspecified or implementation-specific conformance." Contour
  	// chooses to use the first instance of each filter type and ignore
  	// subsequent instances.

[LiorLieberman]

Thanks @sunjayBhatia, done!

[codecov]

Codecov Report

Merging #5652 (413e476) into main (d60959e) will decrease coverage by 0.03%.
Report is 8 commits behind head on main.
The diff coverage is 75.43%.

❗ Current head 413e476 differs from pull request most recent head 91e5942. Consider uploading reports for the commit 91e5942 to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #5652      +/-   ##
==========================================
- Coverage   78.54%   78.51%   -0.03%     
==========================================
  Files         138      138              
  Lines       19046    19058      +12     
==========================================
+ Hits        14959    14964       +5     
- Misses       3803     3808       +5     
- Partials      284      286       +2     

Files Changed	Coverage Δ
internal/dag/dag.go	98.70% <ø> (ø)
internal/debug/dot.go	48.67% <0.00%> (-0.88%)	⬇️
internal/dag/accessors.go	86.66% <50.00%> (-0.33%)	⬇️
internal/dag/gatewayapi_processor.go	93.71% <91.30%> (-0.25%)	⬇️
internal/dag/httpproxy_processor.go	91.80% <100.00%> (ø)
internal/envoy/v3/route.go	80.68% <100.00%> (+0.09%)	⬆️

[sunjayBhatia]

made a tiny unit test nit change to prevent another back and forth on comments, otherwise LGTM