feat(helm): add commonLabels support to helm chart

[gaganhr94]

What type of PR is this?

feat(helm): add commonLabels support to gateway-helm chart

What this PR does / why we need it:

Adds support for commonLabels in the gateway-helm chart, allowing users to apply custom labels to all resources managed by the chart. This is useful for:

• Organizational tagging and resource tracking
• Cost allocation and billing
• Policy enforcement (e.g., Kyverno policies requiring specific labels)

The commonLabels field is now available at the root level of values.yaml and is added to Kubernetes resources through the eg.labels helper template.

Which issue(s) this PR fixes:

Fixes #7913

[netlify]

✅ Deploy Preview for cerulean-figolla-1f9435 ready!

Name	Link
🔨 Latest commit	a15dd88
🔍 Latest deploy log	https://app.netlify.com/projects/cerulean-figolla-1f9435/deploys/69878dd89c960f00084d8f52
😎 Deploy Preview	https://deploy-preview-8078--cerulean-figolla-1f9435.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

---

To edit notification comments on pull requests, go to your Netlify project configuration.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 73.79%. Comparing base (fbea4a7) to head (a15dd88).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #8078      +/-   ##
==========================================
- Coverage   73.80%   73.79%   -0.01%     
==========================================
  Files         241      241              
  Lines       36579    36579              
==========================================
- Hits        26997    26994       -3     
- Misses       7677     7679       +2     
- Partials     1905     1906       +1     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

[gaganhr94]

@arkodg @zirain can you please review this PR and share your thoughts about it. Currently the E2E tests are failing, but they don't look to be directly related to the changes made in this PR

[zirain]

what would happen if there're same keys in eg.selectorLabels and commonLabels?

can you add a test case under test/helm/gatewa-helm?

[gaganhr94]

If the same keys are present in eg.selectorLabels and commonLabels, then the commonLabels value would override. This is an expected behaviour. The same pattern is followed in several bitnami charts and CNCF projects.

I've added the test for this change

[zirain]

can you make CI happy?

rebase with main branch, run make gen-check and commit the changes.

[gaganhr94]

Done @zirain

[zirain]

can you improve these test base on https://github.com/envoyproxy/gateway/pull/8078/changes#r2742524657?
add comment for the override logic.

[gaganhr94]

@zirain, I have added the selectorLabel which will override the default one in the testcase. Just to be clear, in the generated YAML, you will see both the labels - the default one and the one added in commonLabels. When the YAML parser processes the file, it makes sure to consider the value in commonLabels.

[zirain]

it there any tpl in helm to avoid this? or let's comment this behvior in the common-labels.in.yaml

[gaganhr94]

I've commented this behaviour in common-labels.in.yaml clearly now. There are ways in which we can avoid the duplicates. But it is not generally not a pattern followed well known helm-charts, as it makes the _helpers.tpl complex.

[zirain]

Thanks, will merge this after 1.7.0 released to make RM's work easier.