Merge pull request #10567 from adrianreber/2021-06-04-compress

Add support for selectable checkpoint archive compression algorithm

8 files changed, 173 insertions, 22 deletions

diff --git a/cmd/podman/common/completion.go b/cmd/podman/common/completion.go
index de5b2995a..c93f2017c 100644
--- a/cmd/podman/common/completion.go
+++ b/cmd/podman/common/completion.go
@@ -1211,3 +1211,10 @@ func AutocompleteVolumeFilters(cmd *cobra.Command, args []string, toComplete str
 	}
 	return completeKeyValues(toComplete, kv)
 }
+
+// AutocompleteCheckpointCompressType - Autocomplete checkpoint compress type options.
+// -> "gzip", "none", "zstd"
+func AutocompleteCheckpointCompressType(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
+	types := []string{"gzip", "none", "zstd"}
+	return types, cobra.ShellCompDirectiveNoFileComp
+}
diff --git a/cmd/podman/containers/checkpoint.go b/cmd/podman/containers/checkpoint.go
index 47d60453b..4fa72d520 100644
--- a/cmd/podman/containers/checkpoint.go
+++ b/cmd/podman/containers/checkpoint.go
@@ -3,6 +3,7 @@ package containers
 import (
 	"context"
 	"fmt"
+	"strings"
 
 	"github.com/containers/common/pkg/completion"
 	"github.com/containers/podman/v3/cmd/podman/common"
@@ -11,6 +12,7 @@ import (
 	"github.com/containers/podman/v3/cmd/podman/validate"
 	"github.com/containers/podman/v3/pkg/domain/entities"
 	"github.com/containers/podman/v3/pkg/rootless"
+	"github.com/containers/storage/pkg/archive"
 	"github.com/pkg/errors"
 	"github.com/spf13/cobra"
 )
@@ -36,9 +38,7 @@ var (
 	}
 )
 
-var (
-	checkpointOptions entities.CheckpointOptions
-)
+var checkpointOptions entities.CheckpointOptions
 
 func init() {
 	registry.Commands = append(registry.Commands, registry.CliCommand{
@@ -60,11 +60,32 @@ func init() {
 	flags.BoolVarP(&checkpointOptions.PreCheckPoint, "pre-checkpoint", "P", false, "Dump container's memory information only, leave the container running")
 	flags.BoolVar(&checkpointOptions.WithPrevious, "with-previous", false, "Checkpoint container with pre-checkpoint images")
 
+	flags.StringP("compress", "c", "zstd", "Select compression algorithm (gzip, none, zstd) for checkpoint archive.")
+	_ = checkpointCommand.RegisterFlagCompletionFunc("compress", common.AutocompleteCheckpointCompressType)
+
 	validate.AddLatestFlag(checkpointCommand, &checkpointOptions.Latest)
 }
 
 func checkpoint(cmd *cobra.Command, args []string) error {
 	var errs utils.OutputErrors
+	if cmd.Flags().Changed("compress") {
+		if checkpointOptions.Export == "" {
+			return errors.Errorf("--compress can only be used with --export")
+		}
+		compress, _ := cmd.Flags().GetString("compress")
+		switch strings.ToLower(compress) {
+		case "none":
+			checkpointOptions.Compression = archive.Uncompressed
+		case "gzip":
+			checkpointOptions.Compression = archive.Gzip
+		case "zstd":
+			checkpointOptions.Compression = archive.Zstd
+		default:
+			return errors.Errorf("Selected compression algorithm (%q) not supported. Please select one from: gzip, none, zstd", compress)
+		}
+	} else {
+		checkpointOptions.Compression = archive.Zstd
+	}
 	if rootless.IsRootless() {
 		return errors.New("checkpointing a container requires root")
 	}
diff --git a/docs/source/markdown/podman-container-checkpoint.1.md b/docs/source/markdown/podman-container-checkpoint.1.md
index 46b6cb646..271a44c9d 100644
--- a/docs/source/markdown/podman-container-checkpoint.1.md
+++ b/docs/source/markdown/podman-container-checkpoint.1.md
@@ -10,31 +10,25 @@ podman\-container\-checkpoint - Checkpoints one or more running containers
 Checkpoints all the processes in one or more containers. You may use container IDs or names as input.
 
 ## OPTIONS
-#### **--keep**, **-k**
-
-Keep all temporary log and statistics files created by CRIU during checkpointing. These files
-are not deleted if checkpointing fails for further debugging. If checkpointing succeeds these
-files are theoretically not needed, but if these files are needed Podman can keep the files
-for further analysis.
-
 #### **--all**, **-a**
 
 Checkpoint all running containers.
 
-#### **--latest**, **-l**
-
-Instead of providing the container name or ID, checkpoint the last created container. (This option is not available with the remote Podman client)
-
-#### **--leave-running**, **-R**
+#### **--compress**, **-c**
 
-Leave the container running after checkpointing instead of stopping it.
+Specify the compression algorithm used for the checkpoint archive created
+with the **--export, -e** option. Possible algorithms are *gzip*, *none*
+and *zstd*. If no compression algorithm is specified Podman will use
+*zstd*.
 
-#### **--tcp-established**
+One possible reason to use *none* is to enable faster creation of checkpoint
+archives. Not compressing the checkpoint archive can result in faster checkpoint
+archive creation.
 
-Checkpoint a container with established TCP connections. If the checkpoint
-image contains established TCP connections, this options is required during
-restore. Defaults to not checkpointing containers with established TCP
-connections.
+```
+# podman container checkpoint -l --compress=none --export=dump.tar
+# podman container checkpoint -l --compress=gzip --export=dump.tar.gz
+```
 
 #### **--export**, **-e**
 
@@ -56,11 +50,33 @@ This option must be used in combination with the **--export, -e** option.
 When this option is specified, the content of volumes associated with
 the container will not be included into the checkpoint tar.gz file.
 
+#### **--keep**, **-k**
+
+Keep all temporary log and statistics files created by CRIU during checkpointing. These files
+are not deleted if checkpointing fails for further debugging. If checkpointing succeeds these
+files are theoretically not needed, but if these files are needed Podman can keep the files
+for further analysis.
+
+#### **--latest**, **-l**
+
+Instead of providing the container name or ID, checkpoint the last created container. (This option is not available with the remote Podman client)
+
+#### **--leave-running**, **-R**
+
+Leave the container running after checkpointing instead of stopping it.
+
 #### **--pre-checkpoint**, **-P**
 
 Dump the container's memory information only, leaving the container running. Later
 operations will supersede prior dumps. It only works on runc 1.0-rc3 or higher.
 
+#### **--tcp-established**
+
+Checkpoint a container with established TCP connections. If the checkpoint
+image contains established TCP connections, this options is required during
+restore. Defaults to not checkpointing containers with established TCP
+connections.
+
 #### **--with-previous**
 
 Check out the container with previous criu image files in pre-dump. It only works
diff --git a/libpod/container_api.go b/libpod/container_api.go
index 4ccb240e7..b75d0b41d 100644
--- a/libpod/container_api.go
+++ b/libpod/container_api.go
@@ -12,6 +12,7 @@ import (
 	"github.com/containers/podman/v3/libpod/define"
 	"github.com/containers/podman/v3/libpod/events"
 	"github.com/containers/podman/v3/pkg/signal"
+	"github.com/containers/storage/pkg/archive"
 	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
 )
@@ -776,6 +777,9 @@ type ContainerCheckpointOptions struct {
 	// ImportPrevious tells the API to restore container with two
 	// images. One is TargetFile, the other is ImportPrevious.
 	ImportPrevious string
+	// Compression tells the API which compression to use for
+	// the exported checkpoint archive.
+	Compression archive.Compression
 }
 
 // Checkpoint checkpoints a container
diff --git a/libpod/container_internal_linux.go b/libpod/container_internal_linux.go
index 74a3fec32..a3acc3198 100644
--- a/libpod/container_internal_linux.go
+++ b/libpod/container_internal_linux.go
@@ -985,7 +985,7 @@ func (c *Container) exportCheckpoint(options ContainerCheckpointOptions) error {
 	}
 
 	input, err := archive.TarWithOptions(c.bundlePath(), &archive.TarOptions{
-		Compression:      archive.Gzip,
+		Compression:      options.Compression,
 		IncludeSourceDir: true,
 		IncludeFiles:     includeFiles,
 	})
diff --git a/pkg/domain/entities/containers.go b/pkg/domain/entities/containers.go
index eacc14d50..bae55e64f 100644
--- a/pkg/domain/entities/containers.go
+++ b/pkg/domain/entities/containers.go
@@ -9,6 +9,7 @@ import (
 	"github.com/containers/image/v5/types"
 	"github.com/containers/podman/v3/libpod/define"
 	"github.com/containers/podman/v3/pkg/specgen"
+	"github.com/containers/storage/pkg/archive"
 	"github.com/cri-o/ocicni/pkg/ocicni"
 )
 
@@ -178,6 +179,7 @@ type CheckpointOptions struct {
 	TCPEstablished bool
 	PreCheckPoint  bool
 	WithPrevious   bool
+	Compression    archive.Compression
 }
 
 type CheckpointReport struct {
diff --git a/pkg/domain/infra/abi/containers.go b/pkg/domain/infra/abi/containers.go
index 237a43441..4908e72f6 100644
--- a/pkg/domain/infra/abi/containers.go
+++ b/pkg/domain/infra/abi/containers.go
@@ -483,6 +483,7 @@ func (ic *ContainerEngine) ContainerCheckpoint(ctx context.Context, namesOrIds [
 		KeepRunning:    options.LeaveRunning,
 		PreCheckPoint:  options.PreCheckPoint,
 		WithPrevious:   options.WithPrevious,
+		Compression:    options.Compression,
 	}
 
 	if options.All {
diff --git a/test/e2e/checkpoint_test.go b/test/e2e/checkpoint_test.go
index 9d0049910..4aca3682b 100644
--- a/test/e2e/checkpoint_test.go
+++ b/test/e2e/checkpoint_test.go
@@ -425,6 +425,106 @@ var _ = Describe("Podman checkpoint", func() {
 		// Remove exported checkpoint
 		os.Remove(fileName)
 	})
+	// This test does the same steps which are necessary for migrating
+	// a container from one host to another
+	It("podman checkpoint container with export and different compression algorithms", func() {
+		localRunString := getRunString([]string{"--rm", ALPINE, "top"})
+		session := podmanTest.Podman(localRunString)
+		session.WaitWithDefaultTimeout()
+		Expect(session.ExitCode()).To(Equal(0))
+		Expect(podmanTest.NumberOfContainersRunning()).To(Equal(1))
+		cid := session.OutputToString()
+		fileName := "/tmp/checkpoint-" + cid + ".tar"
+
+		// Checkpoint with the default algorithm
+		result := podmanTest.Podman([]string{"container", "checkpoint", "-l", "-e", fileName})
+		result.WaitWithDefaultTimeout()
+
+		// As the container has been started with '--rm' it will be completely
+		// cleaned up after checkpointing.
+		Expect(result.ExitCode()).To(Equal(0))
+		Expect(podmanTest.NumberOfContainersRunning()).To(Equal(0))
+		Expect(podmanTest.NumberOfContainers()).To(Equal(0))
+
+		// Restore container
+		result = podmanTest.Podman([]string{"container", "restore", "-i", fileName})
+		result.WaitWithDefaultTimeout()
+
+		Expect(result.ExitCode()).To(Equal(0))
+		Expect(podmanTest.NumberOfContainersRunning()).To(Equal(1))
+		Expect(podmanTest.GetContainerStatus()).To(ContainSubstring("Up"))
+
+		// Checkpoint with the zstd algorithm
+		result = podmanTest.Podman([]string{"container", "checkpoint", "-l", "-e", fileName, "--compress", "zstd"})
+		result.WaitWithDefaultTimeout()
+
+		// As the container has been started with '--rm' it will be completely
+		// cleaned up after checkpointing.
+		Expect(result.ExitCode()).To(Equal(0))
+		Expect(podmanTest.NumberOfContainersRunning()).To(Equal(0))
+		Expect(podmanTest.NumberOfContainers()).To(Equal(0))
+
+		// Restore container
+		result = podmanTest.Podman([]string{"container", "restore", "-i", fileName})
+		result.WaitWithDefaultTimeout()
+
+		Expect(result.ExitCode()).To(Equal(0))
+		Expect(podmanTest.NumberOfContainersRunning()).To(Equal(1))
+		Expect(podmanTest.GetContainerStatus()).To(ContainSubstring("Up"))
+
+		// Checkpoint with the none algorithm
+		result = podmanTest.Podman([]string{"container", "checkpoint", "-l", "-e", fileName, "-c", "none"})
+		result.WaitWithDefaultTimeout()
+
+		// As the container has been started with '--rm' it will be completely
+		// cleaned up after checkpointing.
+		Expect(result.ExitCode()).To(Equal(0))
+		Expect(podmanTest.NumberOfContainersRunning()).To(Equal(0))
+		Expect(podmanTest.NumberOfContainers()).To(Equal(0))
+
+		// Restore container
+		result = podmanTest.Podman([]string{"container", "restore", "-i", fileName})
+		result.WaitWithDefaultTimeout()
+
+		Expect(result.ExitCode()).To(Equal(0))
+		Expect(podmanTest.NumberOfContainersRunning()).To(Equal(1))
+		Expect(podmanTest.GetContainerStatus()).To(ContainSubstring("Up"))
+
+		// Checkpoint with the gzip algorithm
+		result = podmanTest.Podman([]string{"container", "checkpoint", "-l", "-e", fileName, "-c", "gzip"})
+		result.WaitWithDefaultTimeout()
+
+		// As the container has been started with '--rm' it will be completely
+		// cleaned up after checkpointing.
+		Expect(result.ExitCode()).To(Equal(0))
+		Expect(podmanTest.NumberOfContainersRunning()).To(Equal(0))
+		Expect(podmanTest.NumberOfContainers()).To(Equal(0))
+
+		// Restore container
+		result = podmanTest.Podman([]string{"container", "restore", "-i", fileName})
+		result.WaitWithDefaultTimeout()
+
+		Expect(result.ExitCode()).To(Equal(0))
+		Expect(podmanTest.NumberOfContainersRunning()).To(Equal(1))
+		Expect(podmanTest.GetContainerStatus()).To(ContainSubstring("Up"))
+
+		// Checkpoint with the non-existing algorithm
+		result = podmanTest.Podman([]string{"container", "checkpoint", "-l", "-e", fileName, "-c", "non-existing"})
+		result.WaitWithDefaultTimeout()
+
+		Expect(result.ExitCode()).To(Equal(125))
+		Expect(podmanTest.NumberOfContainersRunning()).To(Equal(1))
+		Expect(podmanTest.NumberOfContainers()).To(Equal(1))
+
+		result = podmanTest.Podman([]string{"rm", "-fa"})
+		result.WaitWithDefaultTimeout()
+		Expect(result.ExitCode()).To(Equal(0))
+		Expect(podmanTest.NumberOfContainersRunning()).To(Equal(0))
+		Expect(podmanTest.NumberOfContainers()).To(Equal(0))
+
+		// Remove exported checkpoint
+		os.Remove(fileName)
+	})
 
 	It("podman checkpoint and restore container with root file-system changes", func() {
 		// Start the container