Add `proxy-url` command line option

[kriswuollett]

What would you like to be added:

Add proxy-url command line option to override cluster setting in selected context config.

Why is this needed:

Golang doesn't support HTTPS_PROXY for localhost addresses as noted in #1653. Avoids the need to statically set proxy urls for each of the clusters defined in a config file.

[k8s-ci-robot]

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[xyz-li]

/assign

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/lifecycle stale

[k8s-triage-robot]

The Kubernetes project currently lacks enough active contributors to adequately respond to all issues.

This bot triages un-triaged issues according to the following rules:

• After 90d of inactivity, lifecycle/stale is applied
• After 30d of inactivity since lifecycle/stale was applied, lifecycle/rotten is applied
• After 30d of inactivity since lifecycle/rotten was applied, the issue is closed

You can:

• Mark this issue as fresh with /remove-lifecycle rotten
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• Offer to help out with Issue Triage

Please send feedback to sig-contributor-experience at kubernetes/community.

/lifecycle rotten

[ardaguclu]

I think you can use kubectl proxy command for this case or modify your host file from localhost to something else. Because Go probably checks the equality of localhost and using something different will enable HTTPS_PROXY env var.

I think, we'd not prefer adding flag for this;

/close

[k8s-ci-robot]

@ardaguclu: Closing this issue.

In response to this:

I think you can use kubectl proxy command for this case or modify your host file from localhost to something else. Because Go probably checks the equality of localhost and using something different will enable HTTPS_PROXY env var.

I think, we'd not prefer adding flag for this;

/close

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