feat: add flagd-proxy HA configuration

[xvzf]

This PR

• Add support for multi-replica flagd-proxy deployments

Related Issues

Fixes #609

Notes

Follow-up Tasks

How to test

Deploy with e.g. FLAGD_PROXY_REPLICA_COUNT=3

[codecov]

Codecov Report

Attention: Patch coverage is 83.58209% with 22 lines in your changes missing coverage. Please review.

Project coverage is 86.25%. Comparing base (499661e) to head (2f6f42c).
Report is 27 commits behind head on main.

Files with missing lines	Patch %	Lines
common/flagdproxy/flagdproxy.go	84.07%	12 Missing and 6 partials ⚠️
controllers/core/featureflagsource/controller.go	63.63%	2 Missing and 2 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #712      +/-   ##
==========================================
- Coverage   86.51%   86.25%   -0.26%     
==========================================
  Files          19       19              
  Lines        1587     1681      +94     
==========================================
+ Hits         1373     1450      +77     
- Misses        173      184      +11     
- Partials       41       47       +6     

Files with missing lines	Coverage Δ
common/utils/utils.go	100.00% <100.00%> (ø)
controllers/core/featureflagsource/controller.go	54.21% <63.63%> (+2.90%)	⬆️
common/flagdproxy/flagdproxy.go	87.90% <84.07%> (-0.80%)	⬇️

... and 1 file with indirect coverage changes

Flag	Coverage Δ
unit-tests	86.25% <83.58%> (-0.26%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

[beeme1mr]

Thanks for the PR! I'll look into the image scanning CI issue, which is unrelated to this change.

[thisthat]

Thank you @xvzf for the PR with some extra refactoring 🙌
I left only some minor comments. In particular, I am not 100% sure if we should retry continuously to reconcile on an unmanaged OFO resource or we should skip it. What's your opinion here?

[beeme1mr]

Hey @xvzf, could you please resolve any open threads that have been resolved? I'll rereview once you're ready. The change looks great so far. Thanks!

[xvzf]

Here we go @beeme1mr @thisthat - been off for a couple of days, sorry for the delay

[thisthat]

Thanks a lot for the contribution @xvzf 🙌

[beeme1mr]

The change is now live in v0.8.0. Thanks @xvzf!

[xvzf]

Thanks for the swift release @beeme1mr!

[beeme1mr]

Hey @xvzf, it looks like this change introduced new permission requirements. Would you be able to update the RBAC configuration?

#717

[wondertroy]

I just noticed when upgrading to open-feature-operator 0.8.0 that previous older flagdProxy resources that already existed did not have this label - and therefore ran in to the 'not managed by OFO' in the ensureFlagdProxyResource method.

It was an easy workaround to manually add this label to the older resources but worth mentioning

[wondertroy]

The previous resources did seem to have the common.ManagedByAnnotationKey: common.ManagedByAnnotationValue, in the Selector though

[xvzf]

Yes, gonna have a look this morning!