feat(trafficrouting): support ingresses with multiple service ports in TrafficRouting.ALB spec

[ArenSH]

Overview

This request introduces new .ServicePorts field for TrafficRouting.ALB to manage ingresses with multiple ports.

Implementation details

There were several options to add ability to manage ingresses with multiple ports:

1. Change behavior and format of .Ingresses field (❌)
   
   Instead of a list of strings, the format of .Ingresses could've been changed to a list of {name: string, servicePorts: []int32} objects. This option is the best one from the consistency and user experience point of view. Unfortunately, it is not possible to implement without introducing braking changes. Even if the controller adjusted to accept both formats (list of strings and list of objects), older clients will fail to interact with the new controller or will overwrite and corrupt .Ingresses field on attempt to change it.

2. Use new api version, like v1alpha2 (❌)
   
   This is a major change, and it should be made by maintainers of the project, not a contributor like me.

3. Add new .ServicePorts field (✅)
   
   Although it adds a bit more confusion to users (having to make sense of ingress/ingresses/servicePort/servicePorts fields), it is the least invasive one. This field is optional and allows specifying multiple ports for some ingresses (other ones will fall back to .ServicePort value)

Changes

The .ServicePorts fields slightly changes behavior and validation of ALBTrafficRouting:

• .ServicePort is now optional field. The validation will check that for all referenced ingresses there is either an entry in .ServicePorts list or .ServicePort is specified as fallback.
• Multiple ports for ingress in .Ingress can be specified using .ServicePorts.
• Each ingress in .Ingresses list must have service ports specified either with an entry in .ServicePorts or with .ServicePort.
• Entries in .ServicePorts must refer to ingress specified in .Ingresses list (or to .Ingress if .Ingresses is nil)

To avoid confusion, it is recommended to use .Ingress + .ServicePort only for a single ingress with a single port. In all other cases .Ingresses + .ServicePorts is preferred.

Links:

• Related Enhancement Proposal: Add support for several servicePorts per ingress using canary via alb plugin #3128

Checklist:

• Either (a) I've created an enhancement proposal and discussed it with the community, (b) this is a bug fix, or (c) this is a chore.
• The title of the PR is (a) conventional with a list of types and scopes found here, (b) states what changed, and (c) suffixes the related issues number. E.g. "fix(controller): Updates such and such. Fixes #1234".
• I've signed my commits with DCO
• I have written unit and/or e2e tests for my change. PRs without these are unlikely to be merged.
• My builds are green. Try syncing with master if they are not.
• My organization is added to USERS.md.

[github-actions]

Go Published Test Results

2 194 tests   2 194 ✅  2m 57s ⏱️
  119 suites      0 💤
    1 files        0 ❌

Results for commit 7dcf17c.

♻️ This comment has been updated with latest results.

[codecov]

Codecov Report

Attention: Patch coverage is 98.80952% with 2 lines in your changes are missing coverage. Please review.

Project coverage is 78.30%. Comparing base (8405f2e) to head (7dcf17c).
Report is 102 commits behind head on master.

Files	Patch %	Lines
rollout/trafficrouting/alb/alb.go	98.82%	1 Missing ⚠️
utils/ingress/ingress.go	98.21%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #3551      +/-   ##
==========================================
- Coverage   81.83%   78.30%   -3.54%     
==========================================
  Files         135      158      +23     
  Lines       20688    18446    -2242     
==========================================
- Hits        16931    14444    -2487     
- Misses       2883     3097     +214     
- Partials      874      905      +31     

☔ View full report in Codecov by Sentry.
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[github-actions]

E2E Tests Published Test Results

  4 files    4 suites   3h 28m 10s ⏱️
110 tests  96 ✅  6 💤  8 ❌
452 runs  416 ✅ 24 💤 12 ❌

For more details on these failures, see this check.

Results for commit 7dcf17c.

♻️ This comment has been updated with latest results.

[sonarcloud]

Quality Gate passed

Issues
41 New issues
0 Accepted issues

Measures
0 Security Hotspots
No data about Coverage
23.4% Duplication on New Code

See analysis details on SonarCloud

[evill]

Great thanks @ArenSH . We were waiting for this feature for a long time to use it in our 30+ services. Possibility to use multi-port will unblock onboarding of ArgoRollouts for our system. Hope to see these feature in next ArgoRollout release :)