dotcloud/docker

package images // import "github.com/docker/docker/daemon/images"

import (
    "context"
    "io"

    "github.com/containerd/log"
    "github.com/docker/docker/container"
    "github.com/docker/docker/image/tarexport"
    ocispec "github.com/opencontainers/image-spec/specs-go/v1"
)

// ExportImage exports a list of images to the given output stream. The
// exported images are archived into a tar when written to the output
// stream. All images with the given tag and all versions containing
// the same tag are exported. names is the set of tags to export, and
// outStream is the writer which the images are written to.
func (i *ImageService) ExportImage(ctx context.Context, names []string, platform *ocispec.Platform, outStream io.Writer) error {
    imageExporter := tarexport.NewTarExporter(i.imageStore, i.layerStore, i.referenceStore, i, platform)
    return imageExporter.Save(ctx, names, outStream)
}

func (i *ImageService) PerformWithBaseFS(ctx context.Context, c *container.Container, fn func(root string) error) error {
    rwlayer, err := i.layerStore.GetRWLayer(c.ID)
    if err != nil {
        return err
    }

    defer func() {
        err := i.ReleaseLayer(rwlayer)
        if err != nil {
            log.G(ctx).WithError(err).WithField("container", c.ID).Warn("Failed to release layer")
        }
    }()

    basefs, err := rwlayer.Mount(c.GetMountLabel())
    if err != nil {
        return err
    }

    defer rwlayer.Unmount()

    return fn(basefs)
}

// LoadImage uploads a set of images into the repository. This is the
// complement of ExportImage.  The input stream is an uncompressed tar
// ball containing images and metadata.
func (i *ImageService) LoadImage(ctx context.Context, inTar io.ReadCloser, platform *ocispec.Platform, outStream io.Writer, quiet bool) error {
    imageExporter := tarexport.NewTarExporter(i.imageStore, i.layerStore, i.referenceStore, i, platform)
    return imageExporter.Load(ctx, inTar, outStream, quiet)
}