output libpod container to kubernetes yaml

scope out new kube subcommand where we can add generate. you can now generate kubernetes
YAML that will allow you to run the container in a kubernetes environment.  When
The YAML description will always "wrap" a container in a simple v1.Pod description.

Tests and further documentation will be added in additional PRs.

This function should be considered very much "under heavy development" at
this point.

Signed-off-by: baude <bbaude@redhat.com>

3 files changed, 116 insertions, 0 deletions

diff --git a/cmd/podman/kube.go b/cmd/podman/kube.go
new file mode 100644
index 000000000..ced87e2bd
--- /dev/null
+++ b/cmd/podman/kube.go
@@ -0,0 +1,22 @@
+package main
+
+import (
+	"github.com/urfave/cli"
+)
+
+var (
+	kubeSubCommands = []cli.Command{
+		containerKubeCommand,
+	}
+
+	kubeDescription = "Work with Kubernetes objects"
+	kubeCommand     = cli.Command{
+		Name:                   "kube",
+		Usage:                  "Import and export Kubernetes objections from and to Podman",
+		Description:            containerDescription,
+		ArgsUsage:              "",
+		Subcommands:            kubeSubCommands,
+		UseShortOptionHandling: true,
+		OnUsageError:           usageErrorHandler,
+	}
+)
diff --git a/cmd/podman/kube_generate.go b/cmd/podman/kube_generate.go
new file mode 100644
index 000000000..a18912668
--- /dev/null
+++ b/cmd/podman/kube_generate.go
@@ -0,0 +1,93 @@
+package main
+
+import (
+	"fmt"
+
+	"github.com/containers/libpod/cmd/podman/libpodruntime"
+	"github.com/containers/libpod/libpod"
+	"github.com/containers/libpod/pkg/rootless"
+	"github.com/ghodss/yaml"
+	"github.com/pkg/errors"
+	"github.com/sirupsen/logrus"
+	"github.com/urfave/cli"
+)
+
+var (
+	containerKubeFlags = []cli.Flag{
+		cli.BoolFlag{
+			Name:  "service, s",
+			Usage: "only generate YAML for kubernetes service object",
+		},
+		LatestFlag,
+	}
+	containerKubeDescription = "Generate Kubernetes Pod YAML"
+	containerKubeCommand     = cli.Command{
+		Name:                   "generate",
+		Usage:                  "Generate Kubernetes pod YAML for a container",
+		Description:            containerKubeDescription,
+		Flags:                  sortFlags(containerKubeFlags),
+		Action:                 generateKubeYAMLCmd,
+		ArgsUsage:              "CONTAINER-NAME",
+		UseShortOptionHandling: true,
+		OnUsageError:           usageErrorHandler,
+	}
+)
+
+// generateKubeYAMLCmdgenerates or replays kube
+func generateKubeYAMLCmd(c *cli.Context) error {
+	var (
+		container *libpod.Container
+		err       error
+		output    []byte
+	)
+
+	if rootless.IsRootless() {
+		return errors.Wrapf(libpod.ErrNotImplemented, "rootless users")
+	}
+	args := c.Args()
+	if len(args) > 1 || (len(args) < 1 && !c.Bool("latest")) {
+		return errors.Errorf("you must provide one container ID or name or --latest")
+	}
+	if c.Bool("service") {
+		return errors.Wrapf(libpod.ErrNotImplemented, "service generation")
+	}
+
+	runtime, err := libpodruntime.GetRuntime(c)
+	if err != nil {
+		return errors.Wrapf(err, "could not get runtime")
+	}
+	defer runtime.Shutdown(false)
+
+	// Get the container in question
+	if c.Bool("latest") {
+		container, err = runtime.GetLatestContainer()
+	} else {
+		container, err = runtime.LookupContainer(args[0])
+	}
+	if err != nil {
+		return err
+	}
+
+	if len(container.Dependencies()) > 0 {
+		return errors.Wrapf(libpod.ErrNotImplemented, "containers with dependencies")
+	}
+
+	podYAML, err := container.InspectForKube()
+	if err != nil {
+		return err
+	}
+
+	developmentComment := []byte("# Generation of Kubenetes YAML is still under development!\n")
+	logrus.Warn("This function is still under heavy development.")
+	// Marshall the results
+	b, err := yaml.Marshal(podYAML)
+	if err != nil {
+		return err
+	}
+	output = append(output, developmentComment...)
+	output = append(output, b...)
+	// Output the v1.Pod with the v1.Container
+	fmt.Println(string(output))
+
+	return nil
+}
diff --git a/cmd/podman/main.go b/cmd/podman/main.go
index 38eac4504..6be192593 100644
--- a/cmd/podman/main.go
+++ b/cmd/podman/main.go
@@ -77,6 +77,7 @@ func main() {
 		infoCommand,
 		inspectCommand,
 		killCommand,
+		kubeCommand,
 		loadCommand,
 		loginCommand,
 		logoutCommand,