Add flag "--listen-address" for docker and podman driver

[Loyen]

Allow a user to set what IP to listen on when binding ports for the docker and podman driver.

Warns the user when used during start.

Example:

$ ./out/minikube-linux-amd64 start --driver=docker --listen-address=0.0.0.0
😄  minikube v1.18.0-beta.0 on Ubuntu 20.04
✨  Using the docker driver based on user configuration
👍  Starting control plane node minikube in cluster minikube
🔥  Creating docker container (CPUs=2, Memory=6300MB) ...
💡  minikube is not meant for production use. You are opening non-local traffic
❗  Listening to 0.0.0.0. This is not recommended and can cause a security vulnerability. Use at your own risk
🐳  Preparing Kubernetes v1.20.2 on Docker 20.10.3 ...
    ▪ Generating certificates and keys ...
    ▪ Booting up control plane ...
    ▪ Configuring RBAC rules ...
🔎  Verifying Kubernetes components...
    ▪ Using image gcr.io/k8s-minikube/storage-provisioner:v4
🌟  Enabled addons: storage-provisioner, default-storageclass
🏄  Done! kubectl is now configured to use "minikube" cluster and "default" namespace by default

Fixes #8008

[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 log a ticket with the Linux Foundation Helpdesk: https://support.linuxfoundation.org/
• Should you encounter any issues with the Linux Foundation Helpdesk, send a message to the backup e-mail support address at: login-issues@jira.linuxfoundation.org

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.

[k8s-ci-robot]

Hi @Loyen. 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.

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.

[k8s-ci-robot]

Welcome @Loyen!

It looks like this is your first PR to kubernetes/minikube 🎉. Please refer to our pull request process documentation to help your PR have a smooth ride to approval.

You will be prompted by a bot to use commands during the review process. Do not be afraid to follow the prompts! It is okay to experiment. Here is the bot commands documentation.

You can also check if kubernetes/minikube has its own contribution guidelines.

You may want to refer to our testing guide if you run into trouble with your tests not passing.

If you are having difficulty getting your pull request seen, please follow the recommended escalation practices. Also, for tips and tricks in the contribution process you may want to read the Kubernetes contributor cheat sheet. We want to make sure your contribution gets all the attention it needs!

Thank you, and welcome to Kubernetes. 😃

[minikube-bot]

Can one of the admins verify this patch?

[medyagh]

thank you @Loyen for this PR as part of this PR please do the following
1- Add warn to user that if they set this flag,
that minikube is NOT meant to be used for production use and this is not recommended and user should assume all the security risks associated with it

2- Validate the listen flag to be a valid listen address. (so if they pass something not parsable we should exit

valdiateListenFlag(...) {
if not ....
exit.WithUsage
}

2-

[Loyen]

Cheers for the feedback @medyagh!

1- Add warn to user that if they set this flag,
that minikube is NOT meant to be used for production use and this is not recommended and user should assume all the security risks associated with it

There's currently a short warning message when you use --listen-address looking like:

Listening to {{.listenAddr}}. Please be advised

I can amend it to have a more informational message.

2- Validate the listen flag to be a valid listen address. (so if they pass something not parsable we should exit

I've now added validation.

[medyagh]

@Loyen do u mind pasting the output of minikube start after this PR in the description of the PR ?

[Loyen]

@medyagh Added the output of start to the description (which includes the "do not use in production" text).

[medyagh]

thank you @Loyen just one small thing left

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: Loyen, medyagh

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 [medyagh]

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

[medyagh]

thank you @Loyen