Add support for checkpoint image

This is an enhancement proposal for the checkpoint / restore feature of
Podman that enables container migration across multiple systems with
standard image distribution infrastructure.

A new option `--create-image <image>` has been added to the
`podman container checkpoint` command. This option tells Podman to
create a container image.  This is a standard image with a single layer,
tar archive, that that contains all checkpoint files. This is similar to
the current approach with checkpoint `--export`/`--import`.

This image can be pushed to a container registry and pulled on a
different system.  It can also be exported locally with `podman image
save` and inspected with `podman inspect`. Inspecting the image would
display additional information about the host and the versions of
Podman, criu, crun/runc, kernel, etc.

`podman container restore` has also been extended to support image
name or ID as input.

Suggested-by: Adrian Reber <areber@redhat.com>
Signed-off-by: Radostin Stoyanov <radostin@redhat.com>

1 files changed, 5 insertions, 0 deletions

diff --git a/libpod/container_internal.go b/libpod/container_internal.go
index c7567a55e..b051b7f2d 100644
--- a/libpod/container_internal.go
+++ b/libpod/container_internal.go
@@ -132,6 +132,11 @@ func (c *Container) ControlSocketPath() string {
 	return filepath.Join(c.bundlePath(), "ctl")
 }
 
+// CheckpointVolumesPath returns the path to the directory containing the checkpointed volumes
+func (c *Container) CheckpointVolumesPath() string {
+	return filepath.Join(c.bundlePath(), metadata.CheckpointVolumesDirectory)
+}
+
 // CheckpointPath returns the path to the directory containing the checkpoint
 func (c *Container) CheckpointPath() string {
 	return filepath.Join(c.bundlePath(), metadata.CheckpointDirectory)