Merge pull request #594 from tonistiigi/override-copy

dockerfile: allow overriding copy image

frontend/dockerfile/builder/build.go

@@ -40,6 +40,7 @@ const (
 	keyImageResolveMode   = "image-resolve-mode"
 	keyGlobalAddHosts     = "add-hosts"
 	keyForceNetwork       = "force-network-mode"
+	keyOverrideCopyImage  = "override-copy-image" // remove after CopyOp implemented
 )
 
 var httpPrefix = regexp.MustCompile("^https?://")
@@ -136,7 +137,11 @@ func Build(ctx context.Context, c client.Client) (*client.Result, error) {
 			return nil, errors.Errorf("failed to read downloaded context")
 		}
 		if isArchive(dt) {
-			unpack := llb.Image(dockerfile2llb.CopyImage, dockerfile2llb.WithInternalName("helper image for file operations")).
+			copyImage := opts[keyOverrideCopyImage]
+			if copyImage == "" {
+				copyImage = dockerfile2llb.DefaultCopyImage
+			}
+			unpack := llb.Image(copyImage, dockerfile2llb.WithInternalName("helper image for file operations")).
 				Run(llb.Shlex("copy --unpack /src/context /out/"), llb.ReadonlyRootFS(), dockerfile2llb.WithInternalName("extracting build context"))
 			unpack.AddMount("/src", httpContext, llb.Readonly)
 			src = unpack.AddMount("/out", llb.Scratch())
@@ -266,6 +271,7 @@ func Build(ctx context.Context, c client.Client) (*client.Result, error) {
 					PrefixPlatform:    exportMap,
 					ExtraHosts:        extraHosts,
 					ForceNetMode:      defaultNetMode,
+					OverrideCopyImage: opts[keyOverrideCopyImage],
 				})
 
 				if err != nil {

frontend/dockerfile/dockerfile2llb/convert.go

@@ -33,7 +33,7 @@ const (
 	localNameContext = "context"
 	historyComment   = "buildkit.dockerfile.v0"
 
-	CopyImage = "tonistiigi/copy:v0.1.3@sha256:e57a3b4d6240f55bac26b655d2cfb751f8b9412d6f7bb1f787e946391fb4b21b"
+	DefaultCopyImage = "tonistiigi/copy:v0.1.3@sha256:e57a3b4d6240f55bac26b655d2cfb751f8b9412d6f7bb1f787e946391fb4b21b"
 )
 
 type ConvertOpt struct {
@@ -55,6 +55,7 @@ type ConvertOpt struct {
 	PrefixPlatform    bool
 	ExtraHosts        []llb.HostIP
 	ForceNetMode      pb.NetMode
+	OverrideCopyImage string
 }
 
 func Dockerfile2LLB(ctx context.Context, dt []byte, opt ConvertOpt) (*llb.State, *Image, error) {
@@ -302,6 +303,10 @@ func Dockerfile2LLB(ctx context.Context, dt []byte, opt ConvertOpt) (*llb.State,
 			buildPlatforms:    platformOpt.buildPlatforms,
 			targetPlatform:    platformOpt.targetPlatform,
 			extraHosts:        opt.ExtraHosts,
+			copyImage:         opt.OverrideCopyImage,
+		}
+		if opt.copyImage == "" {
+			opt.copyImage = DefaultCopyImage
 		}
 
 		if err = dispatchOnBuild(d, d.image.Config.OnBuild, opt); err != nil {
@@ -406,6 +411,7 @@ type dispatchOpt struct {
 	targetPlatform    specs.Platform
 	buildPlatforms    []specs.Platform
 	extraHosts        []llb.HostIP
+	copyImage         string
 }
 
 func dispatch(d *dispatchState, cmd command, opt dispatchOpt) error {
@@ -613,7 +619,7 @@ func dispatchWorkdir(d *dispatchState, c *instructions.WorkdirCommand, commit bo
 
 func dispatchCopy(d *dispatchState, c instructions.SourcesAndDest, sourceState llb.State, isAddCommand bool, cmdToPrint fmt.Stringer, chown string, opt dispatchOpt) error {
 	// TODO: this should use CopyOp instead. Current implementation is inefficient
-	img := llb.Image(CopyImage, llb.MarkImageInternal, llb.Platform(opt.buildPlatforms[0]), WithInternalName("helper image for file operations"))
+	img := llb.Image(opt.copyImage, llb.MarkImageInternal, llb.Platform(opt.buildPlatforms[0]), WithInternalName("helper image for file operations"))
 
 	dest := path.Join(".", pathRelativeToWorkingDir(d.state, c.Dest()))
 	if c.Dest() == "." || c.Dest()[len(c.Dest())-1] == filepath.Separator {