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-rw-r--r--pkg/adapter/checkpoint_restore.go145
1 files changed, 145 insertions, 0 deletions
diff --git a/pkg/adapter/checkpoint_restore.go b/pkg/adapter/checkpoint_restore.go
new file mode 100644
index 000000000..97ba5ecf7
--- /dev/null
+++ b/pkg/adapter/checkpoint_restore.go
@@ -0,0 +1,145 @@
+// +build !remoteclient
+
+package adapter
+
+import (
+ "context"
+ "github.com/containers/libpod/libpod"
+ "github.com/containers/libpod/libpod/image"
+ "github.com/containers/storage/pkg/archive"
+ jsoniter "github.com/json-iterator/go"
+ spec "github.com/opencontainers/runtime-spec/specs-go"
+ "github.com/pkg/errors"
+ "io"
+ "io/ioutil"
+ "os"
+ "path/filepath"
+)
+
+// Prefixing the checkpoint/restore related functions with 'cr'
+
+// crImportFromJSON imports the JSON files stored in the exported
+// checkpoint tarball
+func crImportFromJSON(filePath string, v interface{}) error {
+ jsonFile, err := os.Open(filePath)
+ if err != nil {
+ return errors.Wrapf(err, "Failed to open container definition %s for restore", filePath)
+ }
+ defer jsonFile.Close()
+
+ content, err := ioutil.ReadAll(jsonFile)
+ if err != nil {
+ return errors.Wrapf(err, "Failed to read container definition %s for restore", filePath)
+ }
+ json := jsoniter.ConfigCompatibleWithStandardLibrary
+ if err = json.Unmarshal([]byte(content), v); err != nil {
+ return errors.Wrapf(err, "Failed to unmarshal container definition %s for restore", filePath)
+ }
+
+ return nil
+}
+
+// crImportCheckpoint it the function which imports the information
+// from checkpoint tarball and re-creates the container from that information
+func crImportCheckpoint(ctx context.Context, runtime *libpod.Runtime, input string, name string) ([]*libpod.Container, error) {
+ // First get the container definition from the
+ // tarball to a temporary directory
+ archiveFile, err := os.Open(input)
+ if err != nil {
+ return nil, errors.Wrapf(err, "Failed to open checkpoint archive %s for import", input)
+ }
+ defer archiveFile.Close()
+ options := &archive.TarOptions{
+ // Here we only need the files config.dump and spec.dump
+ ExcludePatterns: []string{
+ "checkpoint",
+ "artifacts",
+ "ctr.log",
+ "network.status",
+ },
+ }
+ dir, err := ioutil.TempDir("", "checkpoint")
+ if err != nil {
+ return nil, err
+ }
+ defer os.RemoveAll(dir)
+ err = archive.Untar(archiveFile, dir, options)
+ if err != nil {
+ return nil, errors.Wrapf(err, "Unpacking of checkpoint archive %s failed", input)
+ }
+
+ // Load spec.dump from temporary directory
+ spec := new(spec.Spec)
+ if err := crImportFromJSON(filepath.Join(dir, "spec.dump"), spec); err != nil {
+ return nil, err
+ }
+
+ // Load config.dump from temporary directory
+ config := new(libpod.ContainerConfig)
+ if err = crImportFromJSON(filepath.Join(dir, "config.dump"), config); err != nil {
+ return nil, err
+ }
+
+ // This should not happen as checkpoints with these options are not exported.
+ if (len(config.Dependencies) > 0) || (len(config.NamedVolumes) > 0) {
+ return nil, errors.Errorf("Cannot import checkpoints of containers with named volumes or dependencies")
+ }
+
+ ctrID := config.ID
+ newName := false
+
+ // Check if the restored container gets a new name
+ if name != "" {
+ config.ID = ""
+ config.Name = name
+ newName = true
+ }
+
+ ctrName := config.Name
+
+ // The code to load the images is copied from create.go
+ var writer io.Writer
+ // In create.go this only set if '--quiet' does not exist.
+ writer = os.Stderr
+ rtc, err := runtime.GetConfig()
+ if err != nil {
+ return nil, err
+ }
+
+ _, err = runtime.ImageRuntime().New(ctx, config.RootfsImageName, rtc.SignaturePolicyPath, "", writer, nil, image.SigningOptions{}, false, nil)
+ if err != nil {
+ return nil, err
+ }
+
+ // Now create a new container from the just loaded information
+ container, err := runtime.RestoreContainer(ctx, spec, config)
+ if err != nil {
+ return nil, err
+ }
+
+ var containers []*libpod.Container
+ if container == nil {
+ return nil, nil
+ }
+
+ containerConfig := container.Config()
+ if containerConfig.Name != ctrName {
+ return nil, errors.Errorf("Name of restored container (%s) does not match requested name (%s)", containerConfig.Name, ctrName)
+ }
+
+ if newName == false {
+ // Only check ID for a restore with the same name.
+ // Using -n to request a new name for the restored container, will also create a new ID
+ if containerConfig.ID != ctrID {
+ return nil, errors.Errorf("ID of restored container (%s) does not match requested ID (%s)", containerConfig.ID, ctrID)
+ }
+ }
+
+ // Check if the ExitCommand points to the correct container ID
+ if containerConfig.ExitCommand[len(containerConfig.ExitCommand)-1] != containerConfig.ID {
+ return nil, errors.Errorf("'ExitCommandID' uses ID %s instead of container ID %s", containerConfig.ExitCommand[len(containerConfig.ExitCommand)-1], containerConfig.ID)
+ }
+
+ containers = append(containers, container)
+ return containers, nil
+}