GEP 1767: CORS Filter

[lianglli]

What type of PR is this?
/kind gep

What this PR does / why we need it:
This GEP proposes to add a new field HTTPCORSFilter to HTTPRouteFilter.

Which issue(s) this PR fixes:
Fixes #1767

Does this PR introduce a user-facing change?:

NONE

[k8s-ci-robot]

Hi @lianglli. Thanks for your PR.

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[youngnick]

Thanks for the energy here @liangli, but the correct process here is for you to add some discussion about this feature to the proposed set of Experimental changes in #3403, and then, if this CORS GEP is selected for an Experimental slot by the community's voting, this PR will be able to move forward.

This is a useful feature that already has a GEP, has been discussed before, and is not too big, so it's reasonably likely that it will be included if we can free up enough Experimental slots by moving things to Standard.

I note that you added this to the 1.2 Experimental discussion as well, so it's fine to just reuse the same description in the v1.3 scoping discussion there so that any new folks will have the context to vote.

Until then, sadly, this PR will need to be on hold.

/hold

[robscott]

Thanks for writing up this GEP @lianglli! This made the cut for v1.3 release scoping, it's great to already have a GEP PR ready for review, will take a look shortly.

/ok-to-test

[robscott]

Thanks for all your work on this @lianglli! This is incredibly detailed and well written. I took a first pass and left some initial comments.

/cc @strongjz @howardjohn @youngnick

[howardjohn]

Thanks for the GEP -- top notch details!

[robscott]

Thanks for all the work on this @lianglli!

/lgtm
/approve
/release-note-none

Although I reopened a couple comment threads that I think could use a bit more discussion, they're clearly small enough to cover when we get into the next phase of the enhancement process with additions to API types.

[mlavacca]

Thanks for the work on this, @lianglli!

/approve

[robscott]

Thanks for all the work on this @lianglli!

I'll hold off on merging this until the most recent comment has been resolved, but IMO this is sufficiently close to keep it in the v1.3 milestone and on to the next phase.

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: lianglli, mlavacca, robscott, spacewander

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[robscott]

Thanks @lianglli!

/lgtm
/hold cancel