mirror of
https://github.com/mudler/luet.git
synced 2025-09-06 01:30:29 +00:00
76 lines
2.1 KiB
Go
76 lines
2.1 KiB
Go
package client
|
|
|
|
import (
|
|
"context"
|
|
"errors"
|
|
"fmt"
|
|
"os"
|
|
|
|
"github.com/containerd/containerd/content"
|
|
"github.com/containerd/containerd/images"
|
|
"github.com/containerd/containerd/platforms"
|
|
"github.com/docker/distribution/reference"
|
|
"github.com/docker/docker/pkg/archive"
|
|
"github.com/sirupsen/logrus"
|
|
)
|
|
|
|
// Unpack exports an image to a rootfs destination directory.
|
|
func (c *Client) Unpack(ctx context.Context, image, dest string) error {
|
|
if len(dest) < 1 {
|
|
return errors.New("destination directory for rootfs cannot be empty")
|
|
}
|
|
|
|
if _, err := os.Stat(dest); err == nil {
|
|
return fmt.Errorf("destination directory already exists: %s", dest)
|
|
}
|
|
|
|
// Parse the image name and tag.
|
|
named, err := reference.ParseNormalizedNamed(image)
|
|
if err != nil {
|
|
return fmt.Errorf("parsing image name %q failed: %v", image, err)
|
|
}
|
|
// Add the latest lag if they did not provide one.
|
|
named = reference.TagNameOnly(named)
|
|
image = named.String()
|
|
|
|
// Create the worker opts.
|
|
opt, err := c.createWorkerOpt(true)
|
|
if err != nil {
|
|
return fmt.Errorf("creating worker opt failed: %v", err)
|
|
}
|
|
|
|
if opt.ImageStore == nil {
|
|
return errors.New("image store is nil")
|
|
}
|
|
|
|
img, err := opt.ImageStore.Get(ctx, image)
|
|
if err != nil {
|
|
return fmt.Errorf("getting image %s from image store failed: %v", image, err)
|
|
}
|
|
|
|
manifest, err := images.Manifest(ctx, opt.ContentStore, img.Target, platforms.Default())
|
|
if err != nil {
|
|
return fmt.Errorf("getting image manifest failed: %v", err)
|
|
}
|
|
|
|
for _, desc := range manifest.Layers {
|
|
logrus.Debugf("Unpacking layer %s", desc.Digest.String())
|
|
|
|
// Read the blob from the content store.
|
|
layer, err := opt.ContentStore.ReaderAt(ctx, desc)
|
|
if err != nil {
|
|
return fmt.Errorf("getting reader for digest %s failed: %v", desc.Digest.String(), err)
|
|
}
|
|
|
|
// Unpack the tarfile to the rootfs path.
|
|
// FROM: https://godoc.org/github.com/moby/moby/pkg/archive#TarOptions
|
|
if err := archive.Untar(content.NewReader(layer), dest, &archive.TarOptions{
|
|
NoLchown: true,
|
|
}); err != nil {
|
|
return fmt.Errorf("extracting tar for %s to directory %s failed: %v", desc.Digest.String(), dest, err)
|
|
}
|
|
}
|
|
|
|
return nil
|
|
}
|