Add minRequestTimeout flag in kube-APIServer

[Sturgelose]

This pull requests adds the minRequestTimeout in kube-apiserver.

The reason to add this flag is to mitigate the issues happening in the watch logic using the python-kubernetes library: kubernetes-client/python-base#57

The reason of the previous issue is that the watch connections timeout and a bug in kubernetes-python code makes any watch throw exception. A temporal solution is to extend the minRequestTimeout flag in kube-apiserver, and thus I'm needing this flag in Kops until the real solution is implemented. (I tested this flag in a local kubeadm installation and works well, but I need now to deploy it in production)

I used the guidelines in the developers documentation to create the PR code. Also, waasn't sure where in the KubeAPIServerConfig structe should I put the new lines to keep it organized, but as it doesn't fit with etcd or auth configuration I just added it separately in the end. If needed, tell me and I move it to a more fitting place in the list.

BTW, it's my first collaboration in the project, so, if there is anything I should change, to which branch I should merge or anything, do not hesitate to tell me about it :)

Anyways, thanks for this great framework! 👍

EDIT: One question:
I've tested it in a local environment and it works.
However, how can I trigger an update in my cluster without having to update to k8s 1.10? Kops 1.10 is in alpha and I'd like to keep it in 1.9.1 until 1.10 is fully stable

[k8s-ci-robot]

Thanks for your pull request. Before we can look at your pull request, you'll need to sign a Contributor License Agreement (CLA).

📝 Please follow instructions at https://git.k8s.io/community/CLA.md#the-contributor-license-agreement to sign the CLA.

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.

---

• 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.
• If you signed the CLA as a corporation, please sign in with your organization's credentials at https://identity.linuxfoundation.org/projects/cncf to be authorized.
• If you have done the above and are still having issues with the CLA being reported as unsigned, please email the CNCF helpdesk: [email protected]

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. I understand the commands that are listed here.

[Sturgelose]

Signed the CLA

[Sturgelose]

/assign @justinsb

[mikesplain]

Hi @Sturgelose thanks for the contribution! This looks pretty good, lets get the tests running first.

As for your question, we generally don't backport features so this will likely be in kops 1.10/1.11. That said, kops versions work with older k8s versions (see here). That said, if you want to try just your changes against "1.9.1", apply your changes to a branch of the 1.9 release branch and you'll be able to test.

/ok-to-test

[justinsb]

Looks great - it's always safe to map the flag (though we don't just map them all because they become part of our API, with our guarantees)

Thanks @Sturgelose!

/approve
/lgtm

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: justinsb, Sturgelose

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 [justinsb]

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