moby/builder/dockerfile/imagecontext.go
Kir Kolyshkin 7d62e40f7e Switch from x/net/context -> context
Since Go 1.7, context is a standard package. Since Go 1.9, everything
that is provided by "x/net/context" is a couple of type aliases to
types in "context".

Many vendored packages still use x/net/context, so vendor entry remains
for now.

Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
2018-04-23 13:52:44 -07:00

121 lines
3 KiB
Go

package dockerfile // import "github.com/docker/docker/builder/dockerfile"
import (
"context"
"runtime"
"github.com/docker/docker/api/types/backend"
"github.com/docker/docker/builder"
dockerimage "github.com/docker/docker/image"
"github.com/pkg/errors"
"github.com/sirupsen/logrus"
)
type getAndMountFunc func(string, bool, string) (builder.Image, builder.ROLayer, error)
// imageSources mounts images and provides a cache for mounted images. It tracks
// all images so they can be unmounted at the end of the build.
type imageSources struct {
byImageID map[string]*imageMount
mounts []*imageMount
getImage getAndMountFunc
}
func newImageSources(ctx context.Context, options builderOptions) *imageSources {
getAndMount := func(idOrRef string, localOnly bool, osForPull string) (builder.Image, builder.ROLayer, error) {
pullOption := backend.PullOptionNoPull
if !localOnly {
if options.Options.PullParent {
pullOption = backend.PullOptionForcePull
} else {
pullOption = backend.PullOptionPreferLocal
}
}
return options.Backend.GetImageAndReleasableLayer(ctx, idOrRef, backend.GetImageAndLayerOptions{
PullOption: pullOption,
AuthConfig: options.Options.AuthConfigs,
Output: options.ProgressWriter.Output,
OS: osForPull,
})
}
return &imageSources{
byImageID: make(map[string]*imageMount),
getImage: getAndMount,
}
}
func (m *imageSources) Get(idOrRef string, localOnly bool, osForPull string) (*imageMount, error) {
if im, ok := m.byImageID[idOrRef]; ok {
return im, nil
}
image, layer, err := m.getImage(idOrRef, localOnly, osForPull)
if err != nil {
return nil, err
}
im := newImageMount(image, layer)
m.Add(im)
return im, nil
}
func (m *imageSources) Unmount() (retErr error) {
for _, im := range m.mounts {
if err := im.unmount(); err != nil {
logrus.Error(err)
retErr = err
}
}
return
}
func (m *imageSources) Add(im *imageMount) {
switch im.image {
case nil:
// set the OS for scratch images
os := runtime.GOOS
// Windows does not support scratch except for LCOW
if runtime.GOOS == "windows" {
os = "linux"
}
im.image = &dockerimage.Image{V1Image: dockerimage.V1Image{OS: os}}
default:
m.byImageID[im.image.ImageID()] = im
}
m.mounts = append(m.mounts, im)
}
// imageMount is a reference to an image that can be used as a builder.Source
type imageMount struct {
image builder.Image
source builder.Source
layer builder.ROLayer
}
func newImageMount(image builder.Image, layer builder.ROLayer) *imageMount {
im := &imageMount{image: image, layer: layer}
return im
}
func (im *imageMount) unmount() error {
if im.layer == nil {
return nil
}
if err := im.layer.Release(); err != nil {
return errors.Wrapf(err, "failed to unmount previous build image %s", im.image.ImageID())
}
im.layer = nil
return nil
}
func (im *imageMount) Image() builder.Image {
return im.image
}
func (im *imageMount) NewRWLayer() (builder.RWLayer, error) {
return im.layer.NewRWLayer()
}
func (im *imageMount) ImageID() string {
return im.image.ImageID()
}