podman pod clone

implement podman pod clone, a command to create an exact copy of a pod while changing
certain config elements

current supported flags are:
--name change the pod name
--destroy remove the original pod
--start run the new pod on creation
and all infra-container related flags from podman pod create (namespaces etc)

resolves #12843

Signed-off-by: cdoern <cdoern@redhat.com>

8 files changed, 134 insertions, 16 deletions

diff --git a/cmd/podman/common/completion.go b/cmd/podman/common/completion.go
index 07dcc4e6a..aeb051001 100644
--- a/cmd/podman/common/completion.go
+++ b/cmd/podman/common/completion.go
@@ -1607,8 +1607,14 @@ func AutocompleteClone(cmd *cobra.Command, args []string, toComplete string) ([]
 	}
 	switch len(args) {
 	case 0:
+		if cmd.Parent().Name() == "pod" { // needs to be " pod " to exclude 'podman'
+			return getPods(cmd, toComplete, completeDefault)
+		}
 		return getContainers(cmd, toComplete, completeDefault)
 	case 2:
+		if cmd.Parent().Name() == "pod" {
+			return nil, cobra.ShellCompDirectiveNoFileComp
+		}
 		return getImages(cmd, toComplete)
 	}
 	return nil, cobra.ShellCompDirectiveNoFileComp
diff --git a/cmd/podman/common/create.go b/cmd/podman/common/create.go
index f89035be3..40bb0df78 100644
--- a/cmd/podman/common/create.go
+++ b/cmd/podman/common/create.go
@@ -98,7 +98,7 @@ func DefineCreateFlags(cmd *cobra.Command, cf *entities.ContainerCreateOptions,
 		cgroupsFlagName := "cgroups"
 		createFlags.StringVar(
 			&cf.CgroupsMode,
-			cgroupsFlagName, cgroupConfig(),
+			cgroupsFlagName, cf.CgroupsMode,
 			`control container cgroup configuration ("enabled"|"disabled"|"no-conmon"|"split")`,
 		)
 		_ = cmd.RegisterFlagCompletionFunc(cgroupsFlagName, AutocompleteCgroupMode)
@@ -150,7 +150,7 @@ func DefineCreateFlags(cmd *cobra.Command, cf *entities.ContainerCreateOptions,
 
 		envFlagName := "env"
 		createFlags.StringArrayP(
-			envFlagName, "e", env(),
+			envFlagName, "e", Env(),
 			"Set environment variables in container",
 		)
 		_ = cmd.RegisterFlagCompletionFunc(envFlagName, completion.AutocompleteNone)
@@ -256,7 +256,7 @@ func DefineCreateFlags(cmd *cobra.Command, cf *entities.ContainerCreateOptions,
 
 		imageVolumeFlagName := "image-volume"
 		createFlags.String(
-			imageVolumeFlagName, containerConfig.Engine.ImageVolumeMode,
+			imageVolumeFlagName, cf.ImageVolume,
 			`Tells podman how to handle the builtin image volumes ("bind"|"tmpfs"|"ignore")`,
 		)
 		_ = cmd.RegisterFlagCompletionFunc(imageVolumeFlagName, AutocompleteImageVolume)
@@ -298,7 +298,7 @@ func DefineCreateFlags(cmd *cobra.Command, cf *entities.ContainerCreateOptions,
 		logDriverFlagName := "log-driver"
 		createFlags.StringVar(
 			&cf.LogDriver,
-			logDriverFlagName, LogDriver(),
+			logDriverFlagName, cf.LogDriver,
 			"Logging driver for the container",
 		)
 		_ = cmd.RegisterFlagCompletionFunc(logDriverFlagName, AutocompleteLogDriver)
@@ -389,7 +389,7 @@ func DefineCreateFlags(cmd *cobra.Command, cf *entities.ContainerCreateOptions,
 		pullFlagName := "pull"
 		createFlags.StringVar(
 			&cf.Pull,
-			pullFlagName, policy(),
+			pullFlagName, cf.Pull,
 			`Pull image before creating ("always"|"missing"|"never")`,
 		)
 		_ = cmd.RegisterFlagCompletionFunc(pullFlagName, AutocompletePullOption)
@@ -406,7 +406,7 @@ func DefineCreateFlags(cmd *cobra.Command, cf *entities.ContainerCreateOptions,
 		)
 		createFlags.BoolVar(
 			&cf.ReadOnlyTmpFS,
-			"read-only-tmpfs", true,
+			"read-only-tmpfs", cf.ReadOnlyTmpFS,
 			"When running containers in read-only mode mount a read-write tmpfs on /run, /tmp and /var/tmp",
 		)
 		requiresFlagName := "requires"
@@ -439,7 +439,7 @@ func DefineCreateFlags(cmd *cobra.Command, cf *entities.ContainerCreateOptions,
 		sdnotifyFlagName := "sdnotify"
 		createFlags.StringVar(
 			&cf.SdNotifyMode,
-			sdnotifyFlagName, define.SdNotifyModeContainer,
+			sdnotifyFlagName, cf.SdNotifyMode,
 			`control sd-notify behavior ("container"|"conmon"|"ignore")`,
 		)
 		_ = cmd.RegisterFlagCompletionFunc(sdnotifyFlagName, AutocompleteSDNotify)
@@ -470,7 +470,7 @@ func DefineCreateFlags(cmd *cobra.Command, cf *entities.ContainerCreateOptions,
 		stopTimeoutFlagName := "stop-timeout"
 		createFlags.UintVar(
 			&cf.StopTimeout,
-			stopTimeoutFlagName, containerConfig.Engine.StopTimeout,
+			stopTimeoutFlagName, cf.StopTimeout,
 			"Timeout (in seconds) that containers stopped by user command have to exit. If exceeded, the container will be forcibly stopped via SIGKILL.",
 		)
 		_ = cmd.RegisterFlagCompletionFunc(stopTimeoutFlagName, completion.AutocompleteNone)
@@ -478,7 +478,7 @@ func DefineCreateFlags(cmd *cobra.Command, cf *entities.ContainerCreateOptions,
 		systemdFlagName := "systemd"
 		createFlags.StringVar(
 			&cf.Systemd,
-			systemdFlagName, "true",
+			systemdFlagName, cf.Systemd,
 			`Run container in systemd mode ("true"|"false"|"always")`,
 		)
 		_ = cmd.RegisterFlagCompletionFunc(systemdFlagName, AutocompleteSystemdFlag)
@@ -522,7 +522,7 @@ func DefineCreateFlags(cmd *cobra.Command, cf *entities.ContainerCreateOptions,
 		timezoneFlagName := "tz"
 		createFlags.StringVar(
 			&cf.Timezone,
-			timezoneFlagName, containerConfig.TZ(),
+			timezoneFlagName, cf.Timezone,
 			"Set timezone in container",
 		)
 		_ = cmd.RegisterFlagCompletionFunc(timezoneFlagName, completion.AutocompleteNone) //TODO: add timezone completion
@@ -530,7 +530,7 @@ func DefineCreateFlags(cmd *cobra.Command, cf *entities.ContainerCreateOptions,
 		umaskFlagName := "umask"
 		createFlags.StringVar(
 			&cf.Umask,
-			umaskFlagName, containerConfig.Umask(),
+			umaskFlagName, cf.Umask,
 			"Set umask in container",
 		)
 		_ = cmd.RegisterFlagCompletionFunc(umaskFlagName, completion.AutocompleteNone)
@@ -538,7 +538,7 @@ func DefineCreateFlags(cmd *cobra.Command, cf *entities.ContainerCreateOptions,
 		ulimitFlagName := "ulimit"
 		createFlags.StringSliceVar(
 			&cf.Ulimit,
-			ulimitFlagName, ulimits(),
+			ulimitFlagName, cf.Ulimit,
 			"Ulimit options",
 		)
 		_ = cmd.RegisterFlagCompletionFunc(ulimitFlagName, completion.AutocompleteNone)
@@ -577,7 +577,7 @@ func DefineCreateFlags(cmd *cobra.Command, cf *entities.ContainerCreateOptions,
 		seccompPolicyFlagName := "seccomp-policy"
 		createFlags.StringVar(
 			&cf.SeccompPolicy,
-			seccompPolicyFlagName, "default",
+			seccompPolicyFlagName, cf.SeccompPolicy,
 			"Policy for selecting a seccomp profile (experimental)",
 		)
 		_ = cmd.RegisterFlagCompletionFunc(seccompPolicyFlagName, completion.AutocompleteDefault)
@@ -769,7 +769,7 @@ func DefineCreateFlags(cmd *cobra.Command, cf *entities.ContainerCreateOptions,
 		volumeFlagName := "volume"
 		createFlags.StringArrayVarP(
 			&cf.Volume,
-			volumeFlagName, "v", volumes(),
+			volumeFlagName, "v", cf.Volume,
 			volumeDesciption,
 		)
 		_ = cmd.RegisterFlagCompletionFunc(volumeFlagName, AutocompleteVolumeFlag)
@@ -890,12 +890,13 @@ func DefineCreateFlags(cmd *cobra.Command, cf *entities.ContainerCreateOptions,
 		memorySwappinessFlagName := "memory-swappiness"
 		createFlags.Int64Var(
 			&cf.MemorySwappiness,
-			memorySwappinessFlagName, -1,
+			memorySwappinessFlagName, cf.MemorySwappiness,
 			"Tune container memory swappiness (0 to 100, or -1 for system default)",
 		)
 		_ = cmd.RegisterFlagCompletionFunc(memorySwappinessFlagName, completion.AutocompleteNone)
 	}
 	// anyone can use these
+
 	cpusFlagName := "cpus"
 	createFlags.Float64Var(
 		&cf.CPUS,
diff --git a/cmd/podman/common/create_opts.go b/cmd/podman/common/create_opts.go
index ad535ff59..fb5af8f59 100644
--- a/cmd/podman/common/create_opts.go
+++ b/cmd/podman/common/create_opts.go
@@ -2,6 +2,8 @@ package common
 
 import (
 	"github.com/containers/podman/v4/cmd/podman/registry"
+	"github.com/containers/podman/v4/libpod/define"
+	"github.com/containers/podman/v4/pkg/domain/entities"
 )
 
 func ulimits() []string {
@@ -25,7 +27,7 @@ func devices() []string {
 	return nil
 }
 
-func env() []string {
+func Env() []string {
 	if !registry.IsRemote() {
 		return containerConfig.Env()
 	}
@@ -73,3 +75,21 @@ func LogDriver() string {
 	}
 	return ""
 }
+
+// DefineCreateDefault is used to initialize ctr create options before flag initialization
+func DefineCreateDefaults(opts *entities.ContainerCreateOptions) {
+	opts.LogDriver = LogDriver()
+	opts.CgroupsMode = cgroupConfig()
+	opts.MemorySwappiness = -1
+	opts.ImageVolume = containerConfig.Engine.ImageVolumeMode
+	opts.Pull = policy()
+	opts.ReadOnlyTmpFS = true
+	opts.SdNotifyMode = define.SdNotifyModeContainer
+	opts.StopTimeout = containerConfig.Engine.StopTimeout
+	opts.Systemd = "true"
+	opts.Timezone = containerConfig.TZ()
+	opts.Umask = containerConfig.Umask()
+	opts.Ulimit = ulimits()
+	opts.SeccompPolicy = "default"
+	opts.Volume = volumes()
+}
diff --git a/cmd/podman/containers/clone.go b/cmd/podman/containers/clone.go
index 6912da1fc..2763adf3c 100644
--- a/cmd/podman/containers/clone.go
+++ b/cmd/podman/containers/clone.go
@@ -41,6 +41,7 @@ func cloneFlags(cmd *cobra.Command) {
 	forceFlagName := "force"
 	flags.BoolVarP(&ctrClone.Force, forceFlagName, "f", false, "force the existing container to be destroyed")
 
+	common.DefineCreateDefaults(&ctrClone.CreateOpts)
 	common.DefineCreateFlags(cmd, &ctrClone.CreateOpts, false, true)
 }
 func init() {
diff --git a/cmd/podman/containers/create.go b/cmd/podman/containers/create.go
index 0a513c606..a214ae8aa 100644
--- a/cmd/podman/containers/create.go
+++ b/cmd/podman/containers/create.go
@@ -71,6 +71,7 @@ func createFlags(cmd *cobra.Command) {
 	)
 
 	flags.SetInterspersed(false)
+	common.DefineCreateDefaults(&cliVals)
 	common.DefineCreateFlags(cmd, &cliVals, false, false)
 	common.DefineNetFlags(cmd)
 
diff --git a/cmd/podman/containers/run.go b/cmd/podman/containers/run.go
index a6c500afa..e49bdaee4 100644
--- a/cmd/podman/containers/run.go
+++ b/cmd/podman/containers/run.go
@@ -61,6 +61,7 @@ func runFlags(cmd *cobra.Command) {
 	flags := cmd.Flags()
 
 	flags.SetInterspersed(false)
+	common.DefineCreateDefaults(&cliVals)
 	common.DefineCreateFlags(cmd, &cliVals, false, false)
 	common.DefineNetFlags(cmd)
 
diff --git a/cmd/podman/pods/clone.go b/cmd/podman/pods/clone.go
new file mode 100644
index 000000000..d95d74b05
--- /dev/null
+++ b/cmd/podman/pods/clone.go
@@ -0,0 +1,87 @@
+package pods
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/containers/common/pkg/completion"
+	"github.com/containers/podman/v4/cmd/podman/common"
+	"github.com/containers/podman/v4/cmd/podman/registry"
+	"github.com/containers/podman/v4/libpod/define"
+	"github.com/containers/podman/v4/pkg/domain/entities"
+	"github.com/pkg/errors"
+	"github.com/spf13/cobra"
+)
+
+var (
+	podCloneDescription = `Create an exact copy of a pod and the containers within it`
+
+	podCloneCommand = &cobra.Command{
+		Use:               "clone [options] POD NAME",
+		Short:             "Clone an existing pod",
+		Long:              podCloneDescription,
+		RunE:              clone,
+		Args:              cobra.RangeArgs(1, 2),
+		ValidArgsFunction: common.AutocompleteClone,
+		Example:           `podman pod clone pod_name new_name`,
+	}
+)
+
+var (
+	podClone entities.PodCloneOptions
+)
+
+func cloneFlags(cmd *cobra.Command) {
+	flags := cmd.Flags()
+
+	destroyFlagName := "destroy"
+	flags.BoolVar(&podClone.Destroy, destroyFlagName, false, "destroy the original pod")
+
+	startFlagName := "start"
+	flags.BoolVar(&podClone.Start, startFlagName, false, "start the new pod")
+
+	nameFlagName := "name"
+	flags.StringVarP(&podClone.CreateOpts.Name, nameFlagName, "n", "", "name the new pod")
+	_ = podCloneCommand.RegisterFlagCompletionFunc(nameFlagName, completion.AutocompleteNone)
+
+	common.DefineCreateDefaults(&podClone.InfraOptions)
+	common.DefineCreateFlags(cmd, &podClone.InfraOptions, true, false)
+	podClone.InfraOptions.MemorySwappiness = -1 // this is not implemented for pods yet, need to set -1 default manually
+
+	// need to fill an empty ctr create option for each container for sane defaults
+	// for now, these cannot be used. The flag names conflict too much
+	// this makes sense since this is a pod command not a container command
+	// TODO: add support for container specific arguments/flags
+	common.DefineCreateDefaults(&podClone.PerContainerOptions)
+}
+func init() {
+	registry.Commands = append(registry.Commands, registry.CliCommand{
+		Command: podCloneCommand,
+		Parent:  podCmd,
+	})
+
+	cloneFlags(podCloneCommand)
+}
+
+func clone(cmd *cobra.Command, args []string) error {
+	switch len(args) {
+	case 0:
+		return errors.Wrapf(define.ErrInvalidArg, "must specify at least 1 argument")
+	case 2:
+		podClone.CreateOpts.Name = args[1]
+	}
+
+	podClone.ID = args[0]
+	podClone.PerContainerOptions.IsClone = true
+	rep, err := registry.ContainerEngine().PodClone(context.Background(), podClone)
+	if err != nil {
+		if rep != nil {
+			fmt.Printf("pod %s created but error after creation\n", rep.Id)
+		}
+		return err
+	}
+
+	fmt.Println(rep.Id)
+
+	return nil
+}
diff --git a/cmd/podman/pods/create.go b/cmd/podman/pods/create.go
index e2f80bdbc..ca9d60174 100644
--- a/cmd/podman/pods/create.go
+++ b/cmd/podman/pods/create.go
@@ -64,6 +64,7 @@ func init() {
 	})
 	flags := createCommand.Flags()
 	flags.SetInterspersed(false)
+	common.DefineCreateDefaults(&infraOptions)
 	common.DefineCreateFlags(createCommand, &infraOptions, true, false)
 	common.DefineNetFlags(createCommand)