kind clusters: replace docker-cli commands with Docker Engine Go Client to improve podman compatibility

[chzar]

Changes

Replaced the docker-cli commands in kind.go with github.com/docker/docker/client

/kind enhancement

Fixes #408
Fixes #528

Release Note

Improves cross compatibility between users of docker and podman (if docker compatibility mode is enabled). Removes the requirement of installing docker-cli for podman users.

Docs

Podman users should be instructed to enable Docker compatibility mode

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: chzar (9f08901, abaa71c, fa3f89d, a73365d, 56e99e2)

[knative-prow]

Welcome @chzar! It looks like this is your first PR to knative-extensions/kn-plugin-quickstart 🎉

[knative-prow]

Hi @chzar. Thanks for your PR.

I'm waiting for a knative-extensions 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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[psschwei]

Thanks for the PR! You'll need to sign the CLA before we can merge this.
/ok-to-test

[chzar]

Thanks for the PR! You'll need to sign the CLA before we can merge this. /ok-to-test

Signed, sealed, delivered.

[psschwei]

When trying this with podman, I got the following error:

Command Output: Error: rootlessport cannot expose privileged port 80, you can add 'net.ipv4.ip_unprivileged_port_start=80' to /etc/sysctl.conf (currently 1024), or choose a larger port number (>= 1024): listen tcp 0.0.0.0:80: bind: permission denied

I don't use podman on a regular basis, so not sure if regular podman users would already have a workaround for the port issue or if we should think about changing the host port on the cluster...

With docker, everything worked fine.

[chzar]

I am on macOS and using podman machine so kind works out of the box.

Perhaps changing to port 8080 or 9000 would be more appropriate for a test/demo setup?

[psschwei]

Perhaps changing to port 8080 or 9000 would be more appropriate for a test/demo setup?

Yeah, I think that makes sense... would you want to do that change too?

[chzar]

Sure. I can make a separate PR.

This change should work for all MacOS/Windows users of docker/podman. For Linux users, the restrictions on binding Port 80 have always been present for both docker and podman - so nothing is broken that wasn't so before.

[psschwei]

I think we need to check if a registry container is running first

[chzar]

Why would it matter if the container was running or stopped?

[psschwei]

Sorry, shouldn't have used the word "running" in my original comment... the issue isn't whether the registry container is running or stopped but rather if it exists or not.

Because the deleteContainerRegistry() method now returns an error, the whole quickstart will fail if the registry container doesn't exist.

$ ./kn-quickstart kind --registry
Running Knative Quickstart using Kind
✅ Checking dependencies...
    Kind version is: 0.23.0
💽 Installing local registry...
Pulling from library/registry: 2
Digest: sha256:ac0192b549007e22998eb74e8d8488dcfe70f1489520c3b144a6047ac5efbe90: %!s(<nil>)
Status: Image is up to date for registry:2: %!s(<nil>)
Error: creating cluster: failed to delete local registry: failed remove registry container: Error response from daemon: No such container: kind-registry

whereas before quickstart wouldn't fail when trying to delete a non-existent registry.

[chzar]

Now I follow you. I will improve the error handling such that it does not return an error in this case instead of trying to check for the existence of the registry prior to deletion. It's possible that the registry container is deleted by another client prior to my delete container api call.

[psschwei]

Thanks!
/lgtm
/approve

[knative-prow]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: chzar, psschwei

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