docker/docker

package images

import (
    "context"

    "github.com/docker/docker/image"
    "github.com/docker/docker/layer"
    "github.com/pkg/errors"
)

// GetContainerLayerSize returns real size & virtual size
func (i *ImageService) GetContainerLayerSize(ctx context.Context, containerID string) (int64, int64, error) {
    // TODO Windows
    return 0, 0, nil
}

// GetLayerFolders returns the layer folders from an image RootFS
func (i *ImageService) GetLayerFolders(img *image.Image, rwLayer layer.RWLayer, containerID string) ([]string, error) {
    folders := []string{}
    rd := len(img.RootFS.DiffIDs)
    for index := 1; index <= rd; index++ {
        // FIXME: why does this mutate the RootFS?
        img.RootFS.DiffIDs = img.RootFS.DiffIDs[:index]
        if err := image.CheckOS(img.OperatingSystem()); err != nil {
            return nil, errors.Wrapf(err, "cannot get layerpath for ImageID %s", img.RootFS.ChainID())
        }
        layerPath, err := layer.GetLayerPath(i.layerStore, img.RootFS.ChainID())
        if err != nil {
            return nil, errors.Wrapf(err, "failed to get layer path from graphdriver %s for ImageID %s", i.layerStore, img.RootFS.ChainID())
        }
        // Reverse order, expecting parent first
        folders = append([]string{layerPath}, folders...)
    }
    if rwLayer == nil {
        return nil, errors.New("RWLayer is unexpectedly nil")
    }
    m, err := rwLayer.Metadata()
    if err != nil {
        return nil, errors.Wrap(err, "failed to get layer metadata")
    }
    return append(folders, m["dir"]), nil
}