Implement Podman Container Clone

podman container clone takes the id of an existing continer and creates a specgen from the given container's config
recreating all proper namespaces and overriding spec options like resource limits and the container name if given in the cli options

this command utilizes the common function DefineCreateFlags meaning that we can funnel as many create options as we want
into clone over time allowing the user to clone with as much or as little of the original config as they want.

container clone takes a second argument which is a new name and a third argument which is an image name to use instead of the original container's

the current supported flags are:

--destroy (remove the original container)
--name (new ctr name)
--cpus (sets cpu period and quota)
--cpuset-cpus
--cpu-period
--cpu-rt-period
--cpu-rt-runtime
--cpu-shares
--cpuset-mems
--memory
--run

resolves #10875

Signed-off-by: cdoern <cdoern@redhat.com>
Signed-off-by: cdoern <cbdoer23@g.holycross.edu>
Signed-off-by: cdoern <cdoern@redhat.com>

6 files changed, 107 insertions, 4 deletions

diff --git a/pkg/domain/entities/containers.go b/pkg/domain/entities/containers.go
index d39a70732..e9bce0eb7 100644
--- a/pkg/domain/entities/containers.go
+++ b/pkg/domain/entities/containers.go
@@ -463,3 +463,13 @@ type ContainerRenameOptions struct {
 	// NewName is the new name that will be given to the container.
 	NewName string
 }
+
+// ContainerCloneOptions contains options for cloning an existing continer
+type ContainerCloneOptions struct {
+	ID           string
+	Destroy      bool
+	CreateOpts   ContainerCreateOptions
+	Image        string
+	RawImageName string
+	Run          bool
+}
diff --git a/pkg/domain/entities/engine_container.go b/pkg/domain/entities/engine_container.go
index 5dedceacc..21272d33f 100644
--- a/pkg/domain/entities/engine_container.go
+++ b/pkg/domain/entities/engine_container.go
@@ -19,6 +19,7 @@ type ContainerEngine interface {
 	ContainerAttach(ctx context.Context, nameOrID string, options AttachOptions) error
 	ContainerCheckpoint(ctx context.Context, namesOrIds []string, options CheckpointOptions) ([]*CheckpointReport, error)
 	ContainerCleanup(ctx context.Context, namesOrIds []string, options ContainerCleanupOptions) ([]*ContainerCleanupReport, error)
+	ContainerClone(ctx context.Context, ctrClone ContainerCloneOptions) (*ContainerCreateReport, error)
 	ContainerCommit(ctx context.Context, nameOrID string, options CommitOptions) (*CommitReport, error)
 	ContainerCopyFromArchive(ctx context.Context, nameOrID, path string, reader io.Reader, options CopyOptions) (ContainerCopyFunc, error)
 	ContainerCopyToArchive(ctx context.Context, nameOrID string, path string, writer io.Writer) (ContainerCopyFunc, error)
diff --git a/pkg/domain/entities/pods.go b/pkg/domain/entities/pods.go
index 7922db4e6..6fb3db1b5 100644
--- a/pkg/domain/entities/pods.go
+++ b/pkg/domain/entities/pods.go
@@ -264,6 +264,7 @@ type ContainerCreateOptions struct {
 	SeccompPolicy     string
 	PidFile           string
 	IsInfra           bool
+	IsClone           bool
 
 	Net *NetOptions `json:"net,omitempty"`
 
diff --git a/pkg/domain/infra/abi/containers.go b/pkg/domain/infra/abi/containers.go
index a5c4647d7..92f5b1a80 100644
--- a/pkg/domain/infra/abi/containers.go
+++ b/pkg/domain/infra/abi/containers.go
@@ -6,6 +6,7 @@ import (
 	"io/ioutil"
 	"os"
 	"strconv"
+	"strings"
 	"sync"
 	"time"
 
@@ -648,7 +649,7 @@ func (ic *ContainerEngine) ContainerCreate(ctx context.Context, s *specgen.SpecG
 	for _, w := range warn {
 		fmt.Fprintf(os.Stderr, "%s\n", w)
 	}
-	rtSpec, spec, opts, err := generate.MakeContainer(context.Background(), ic.Libpod, s)
+	rtSpec, spec, opts, err := generate.MakeContainer(context.Background(), ic.Libpod, s, false, nil)
 	if err != nil {
 		return nil, err
 	}
@@ -971,7 +972,7 @@ func (ic *ContainerEngine) ContainerRun(ctx context.Context, opts entities.Conta
 		fmt.Fprintf(os.Stderr, "%s\n", w)
 	}
 
-	rtSpec, spec, optsN, err := generate.MakeContainer(ctx, ic.Libpod, opts.Spec)
+	rtSpec, spec, optsN, err := generate.MakeContainer(ctx, ic.Libpod, opts.Spec, false, nil)
 	if err != nil {
 		return nil, err
 	}
@@ -1490,3 +1491,89 @@ func (ic *ContainerEngine) ContainerRename(ctx context.Context, nameOrID string,
 
 	return nil
 }
+
+func (ic *ContainerEngine) ContainerClone(ctx context.Context, ctrCloneOpts entities.ContainerCloneOptions) (*entities.ContainerCreateReport, error) {
+	spec := specgen.NewSpecGenerator(ctrCloneOpts.Image, ctrCloneOpts.CreateOpts.RootFS)
+	var c *libpod.Container
+	c, err := generate.ConfigToSpec(ic.Libpod, spec, ctrCloneOpts.ID)
+	if err != nil {
+		return nil, err
+	}
+
+	err = specgenutil.FillOutSpecGen(spec, &ctrCloneOpts.CreateOpts, []string{})
+	if err != nil {
+		return nil, err
+	}
+	out, err := generate.CompleteSpec(ctx, ic.Libpod, spec)
+	if err != nil {
+		return nil, err
+	}
+
+	// Print warnings
+	if len(out) > 0 {
+		for _, w := range out {
+			fmt.Println("Could not properly complete the spec as expected:")
+			fmt.Fprintf(os.Stderr, "%s\n", w)
+		}
+	}
+
+	if len(ctrCloneOpts.CreateOpts.Name) > 0 {
+		spec.Name = ctrCloneOpts.CreateOpts.Name
+	} else {
+		n := c.Name()
+		_, err := ic.Libpod.LookupContainer(c.Name() + "-clone")
+		if err == nil {
+			n += "-clone"
+		}
+		switch {
+		case strings.Contains(n, "-clone"):
+			ind := strings.Index(n, "-clone") + 6
+			num, _ := strconv.Atoi(n[ind:])
+			if num == 0 { // clone1 is hard to get with this logic, just check for it here.
+				_, err = ic.Libpod.LookupContainer(n + "1")
+				if err != nil {
+					spec.Name = n + "1"
+					break
+				}
+			} else {
+				n = n[0:ind]
+			}
+			err = nil
+			count := num
+			for err == nil {
+				count++
+				tempN := n + strconv.Itoa(count)
+				_, err = ic.Libpod.LookupContainer(tempN)
+			}
+			n += strconv.Itoa(count)
+			spec.Name = n
+		default:
+			spec.Name = c.Name() + "-clone"
+		}
+	}
+
+	rtSpec, spec, opts, err := generate.MakeContainer(context.Background(), ic.Libpod, spec, true, c)
+	if err != nil {
+		return nil, err
+	}
+	ctr, err := generate.ExecuteCreate(ctx, ic.Libpod, rtSpec, spec, false, opts...)
+	if err != nil {
+		return nil, err
+	}
+
+	if ctrCloneOpts.Destroy {
+		var time *uint
+		err := ic.Libpod.RemoveContainer(context.Background(), c, false, false, time)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	if ctrCloneOpts.Run {
+		if err := ctr.Start(ctx, true); err != nil {
+			return nil, err
+		}
+	}
+
+	return &entities.ContainerCreateReport{Id: ctr.ID()}, nil
+}
diff --git a/pkg/domain/infra/abi/play.go b/pkg/domain/infra/abi/play.go
index cad8c4609..25e8f8556 100644
--- a/pkg/domain/infra/abi/play.go
+++ b/pkg/domain/infra/abi/play.go
@@ -392,7 +392,7 @@ func (ic *ContainerEngine) playKubePod(ctx context.Context, podName string, podY
 		if err != nil {
 			return nil, err
 		}
-		rtSpec, spec, opts, err := generate.MakeContainer(ctx, ic.Libpod, specGen)
+		rtSpec, spec, opts, err := generate.MakeContainer(ctx, ic.Libpod, specGen, false, nil)
 		if err != nil {
 			return nil, err
 		}
@@ -435,7 +435,7 @@ func (ic *ContainerEngine) playKubePod(ctx context.Context, podName string, podY
 			if err != nil {
 				return nil, err
 			}
-			rtSpec, spec, opts, err := generate.MakeContainer(ctx, ic.Libpod, specGen)
+			rtSpec, spec, opts, err := generate.MakeContainer(ctx, ic.Libpod, specGen, false, nil)
 			if err != nil {
 				return nil, err
 			}
diff --git a/pkg/domain/infra/tunnel/containers.go b/pkg/domain/infra/tunnel/containers.go
index 67e709486..aa4baf846 100644
--- a/pkg/domain/infra/tunnel/containers.go
+++ b/pkg/domain/infra/tunnel/containers.go
@@ -958,3 +958,7 @@ func (ic *ContainerEngine) ShouldRestart(_ context.Context, id string) (bool, er
 func (ic *ContainerEngine) ContainerRename(ctx context.Context, nameOrID string, opts entities.ContainerRenameOptions) error {
 	return containers.Rename(ic.ClientCtx, nameOrID, new(containers.RenameOptions).WithName(opts.NewName))
 }
+
+func (ic *ContainerEngine) ContainerClone(ctx context.Context, ctrCloneOpts entities.ContainerCloneOptions) (*entities.ContainerCreateReport, error) {
+	return nil, errors.New("cloning a container is not supported on the remote client")
+}