Is the docker compatibility API drifting from spec?

[chesedo]

This is somewhat related to #14513, but with a concrete example from the code.

I might understand things wrong because I don't completely understand the docker compatibility API - in which case please correct me. However it seems that the following is all that is needed to start the compat API:

podman system service -t 5000 &

Now from the docker API it seems container inspect should return a status.status string with one of the following:

• created
• running
• paused
• restarting
• removing
• exited
• dead

However, in this libpod code in seems status can also return initialized

podman/libpod/define/containerstate.go

Lines 43 to 71 in 7371306

	func (t ContainerStatus) String() string {
	switch t {
	case ContainerStateUnknown:
	return "unknown"
	case ContainerStateConfigured:
	// The naming here is confusing, but it's necessary for Docker
	// compatibility - their Created state is our Configured state.
	return "created"
	case ContainerStateCreated:
	// Docker does not have an equivalent to this state, so give it
	// a clear name. Most of the time this is a purely transitory
	// state between Configured and Running so we don't expect to
	// see it much anyways.
	return "initialized"
	case ContainerStateRunning:
	return "running"
	case ContainerStateStopped:
	return "stopped"
	case ContainerStatePaused:
	return "paused"
	case ContainerStateExited:
	return "exited"
	case ContainerStateRemoving:
	return "removing"
	case ContainerStateStopping:
	return "stopping"
	}
	return "bad state"
	}

Am I looking at the correct docker compatibility API code? Should it be drifting from the docker spec?

[Luap99]

These are just the internal libpod names that are exposed via the podman cli. The docker compat api should always return correct docker output, if not file a bug with a reproducer.
This is the compat api code:

podman/pkg/api/handlers/compat/containers.go

Line 277 in c936d1e

func LibpodToContainer(l *libpod.Container, sz bool) (*handlers.Container, error) {

[chesedo]

Thanks, I was looking at the wrong file 😁

This is a bit hard to reproduce as we don't see it often - the comment in libpod also states "we don't expect to see it [initialized] much" 😅

But I tried to explain my logic in PR #14700

[mheon]

You can manually get an Initialized container by running podman init on a container in the Created state