feat: New istio config format

[pastequo]

Changes

• Introduce new configuration format

/kind enhancement

Fixes #1247

Release Note

A new configuration format has been introduced. Old format is still supported. See https://docs.google.com/document/d/12X1-9nhjAhpf-Wlt3RbdoMbvx31zFBva/edit for more details

Docs

[knative-prow]

Hi @pastequo. Thanks for your PR.

I'm waiting for a knative-extensions member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

I understand the commands that are listed here.

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

[codecov]

Codecov Report

Attention: 3 lines in your changes are missing coverage. Please review.

Comparison is base (9a51ff3) 81.54% compared to head (c29c707) 82.10%.
Report is 3 commits behind head on main.

❗ Current head c29c707 differs from pull request most recent head 5ead169. Consider uploading reports for the commit 5ead169 to get more accurate results

Files	Patch %	Lines
pkg/reconciler/ingress/config/istio.go	96.77%	2 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1249      +/-   ##
==========================================
+ Coverage   81.54%   82.10%   +0.56%     
==========================================
  Files          19       19              
  Lines        1669     1738      +69     
==========================================
+ Hits         1361     1427      +66     
- Misses        220      222       +2     
- Partials       88       89       +1     

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

[dprotaso]

/ok-to-test

[dprotaso]

/retest

[dprotaso]

Technically just specifying external-gateways is a valid config and we would default the local gateway to what's defined here:

net-istio/pkg/reconciler/ingress/config/istio.go

Lines 69 to 75 in c29c707

	func defaultLocalGateways() []Gateway {
	return []Gateway{{
	Namespace: system.Namespace(),
	Name: KnativeLocalGateway,
	ServiceURL: network.GetServiceHostname(KnativeLocalGateway, IstioNamespace),
	}}
	}

Same applies to vice-versa where the user defines only the local-gateways key

I think it would be simpler to just look at the presence of the new keys in NewIstioFromConfigMap and if they're present assume it's the new config map format. Otherwise fallback onto the older parsing.

[pastequo]

So I implemented the following

• If both format are defined (even partially), the code will error
• default values are used either by the new or old format

I let you resolve the thread if this new version is ok for you

[pastequo]

/retest

[pastequo]

/retest

[dprotaso]

/lgtm
/approve

[knative-prow]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: dprotaso, pastequo

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Needs approval from an approver in each of these files:

• OWNERS [dprotaso]

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment