Add support for specifying CNI networks in podman play kube

[cfelder]

As far as I understood it is not possible to define container network on the yaml level (https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.18/#pod-v1-core).

I am adding networking options to podman play cube though.

[mheon]

I don't know if we want to do this - should we be sourcing from the Kube YAML instead? @haircommander thoughts?

[cfelder]

@mheon I would prefer specifying this on yaml level but I have not found an option to declare a network for a pod in the specs.

[haircommander]

yeah I also wouldn't go the flag route. There are some first class pod API features that relate to pod networking:

the dnsConfig object would take care of --dns --dns-opt and --dns-search
hostAliases seem to take care of --add-hosts and --ip

finally, you can replicate --publish on the container level with the ports object

there doesn't seem to be a way to specify --mac-address, and --network also seems inaccessible. It is also hard to figure out how similar behavior to --no-hosts could be implemented.

[haircommander]

I suppose --network could be added as a hacky way to specify a network (Because k8s api doesn't provide it). But the others should be done the k8s way IMO

[cfelder]

I am more than happy to implement this in yaml if you can help me with the specification as I don't know how to specify the network options in yaml syntax.

it would be a lot easier to implement this in PlayKubeYAML in pkg/adapter/pods.go using libPod.WithPodNetworks.

[haircommander]

I am more than happy to implement this in yaml if you can help me with the specification as I don't know how to specify the network options in yaml syntax.

were the above links not enough to get started? do you have specific questions about them?

it would be a lot easier to implement this in PlayKubeYAML in pkg/adapter/pods.go using libPod.WithPodNetworks.

As an example, when iterating through the container objects, you can access container.Ports and take the information defined here and translate it into the equivalent values for libpod/options:WithNetNS()

does that help?

[haircommander]

I am more than happy to implement this in yaml if you can help me with the specification as I don't know how to specify the network options in yaml syntax.

were the above links not enough to get started? do you have specific questions about them?

it would be a lot easier to implement this in PlayKubeYAML in pkg/adapter/pods.go using libPod.WithPodNetworks.

As an example, when iterating through the container objects, you can access container.Ports and take the information defined here and translate it into the equivalent values for libpod/options:WithNetNS()

does that help?

nvm on that, we already do something similar in getPodPorts in pkg/adapter/pods.go . but hopefully that serves as an example for the other options

[cfelder]

Thanks for your remarks I changed my PR to just add --network for podman play kube in order to support specifying CNI networks which cannot be done in yaml syntax right now.

[mheon]

Concur that just --network is appropriate...

We probably also want to restrict it to only listing a set of CNI networks - we should not support --net=host and --net=bridge as those are handled in the YAML.

[TomSweeneyRedHat]

Any tests possible? Code LGTM, just a few nitty doc things. Thanks @cfelder !

[vrothberg]

Ping. Let's get this in.

[mheon]

/approve
LGTM

[openshift-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: cfelder, mheon

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 [mheon]

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

[haircommander]

/lgtm