added proxy-http-version annotation to override the HTTP/1.1 default …

[eshicks4]

…connection type to reverse proxy backends

What this PR does / why we need it:

Adds an annotation that allows us to downgrade the backend proxy connections to HTTP/1.0 if desired. This allows us to mitigate certain issues with Nginx and/or misbehaving backends. (i.e. Nginx doesn't process "100 Continue" responses correctly and some backends will send it even if no "Expect" header is provided)

Special notes for your reviewer:

1st time submitter - please be patient with me. I've had this deployed for about a week now as the primary ingress for Ohio State University's Kube cluster and (so far) no issues.

[k8s-ci-robot]

Hi @eshicks4. Thanks for your PR.

I'm waiting for a kubernetes 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.

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[aledbf]

@eshicks4 this look good. Please sign the CLA so we can start testing this change.

[eshicks4]

It may take a couple minutes for the CLA signature to be fully registered; after that, please reply here with a new comment and we'll verify. Thanks.

Thought I had. How long does it generally take to register?

[aledbf]

/check-cla

[aledbf]

If you've already signed a CLA, it's possible we don't have your GitHub username or you're using a different email address. Check your existing CLA data and verify that your email is set on your git commits.

@eshicks4 check ^^

[aledbf]

/ok-to-test

[codecov-io]

Codecov Report

Merging #4288 into master will decrease coverage by 0.71%.
The diff coverage is 71.42%.

@@            Coverage Diff             @@
##           master    #4288      +/-   ##
==========================================
- Coverage   58.23%   57.51%   -0.72%     
==========================================
  Files          87       87              
  Lines        6489     6942     +453     
==========================================
+ Hits         3779     3993     +214     
- Misses       2282     2442     +160     
- Partials      428      507      +79

Impacted Files	Coverage Δ
internal/ingress/controller/config/config.go	98.57% <100%> (+0.01%)	⬆️
internal/ingress/controller/controller.go	46.69% <100%> (+0.06%)	⬆️
internal/ingress/annotations/proxy/main.go	59.13% <60%> (+0.04%)	⬆️
internal/k8s/main.go	59.25% <0%> (-1.12%)	⬇️
internal/ingress/annotations/ratelimit/main.go	63.15% <0%> (+1.47%)	⬆️
internal/ingress/controller/nginx.go	30.96% <0%> (+1.74%)	⬆️
internal/ingress/types_equals.go	22.55% <0%> (+3.32%)	⬆️
internal/net/ssl/ssl.go	56.86% <0%> (+6.86%)	⬆️
internal/ingress/annotations/ipwhitelist/main.go	73.17% <0%> (+17.99%)	⬆️

---

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[eshicks4]

That was it. I'd added my OSU email but hadn't verified it yet.

[aledbf]

/approve

[ElvinEfendi]

/lgtm

Thanks!

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: aledbf, ElvinEfendi, eshicks4

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Needs approval from an approver in each of these files:

• OWNERS [ElvinEfendi,aledbf]

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