Added --image-name-with-digest flag

cmd/executor/cmd/root.go

@@ -70,6 +70,9 @@ var RootCmd = &cobra.Command{
 			if err := resolveDockerfilePath(); err != nil {
 				return errors.Wrap(err, "error resolving dockerfile path")
 			}
+			if len(opts.Destinations) == 0 && opts.ImageNameDigestFile != "" {
+				return errors.New("You must provide --destination if setting ImageNameDigestFile")
+			}
 		}
 		return nil
 	},
@@ -134,6 +137,7 @@ func addKanikoOptionsFlags(cmd *cobra.Command) {
 	RootCmd.PersistentFlags().StringVarP(&opts.CacheRepo, "cache-repo", "", "", "Specify a repository to use as a cache, otherwise one will be inferred from the destination provided")
 	RootCmd.PersistentFlags().StringVarP(&opts.CacheDir, "cache-dir", "", "/cache", "Specify a local directory to use as a cache.")
 	RootCmd.PersistentFlags().StringVarP(&opts.DigestFile, "digest-file", "", "", "Specify a file to save the digest of the built image to.")
+	RootCmd.PersistentFlags().StringVarP(&opts.ImageNameDigestFile, "image-name-with-digest-file", "", "", "Specify a file to save the image name w/ digest of the built image to.")
 	RootCmd.PersistentFlags().StringVarP(&opts.OCILayoutPath, "oci-layout-path", "", "", "Path to save the OCI image layout of the built image.")
 	RootCmd.PersistentFlags().BoolVarP(&opts.Cache, "cache", "", false, "Use cache when building image")
 	RootCmd.PersistentFlags().BoolVarP(&opts.Cleanup, "cleanup", "", false, "Clean the filesystem at the end")
@@ -240,6 +244,7 @@ func resolveRelativePaths() error {
 		&opts.CacheDir,
 		&opts.TarPath,
 		&opts.DigestFile,
+		&opts.ImageNameDigestFile,
 	}
 
 	for _, p := range optsPaths {

pkg/config/options.go

@@ -37,6 +37,7 @@ type KanikoOptions struct {
 	Target                  string
 	CacheRepo               string
 	DigestFile              string
+	ImageNameDigestFile     string
 	OCILayoutPath           string
 	Destinations            multiArg
 	BuildArgs               multiArg

pkg/executor/push.go

@@ -96,17 +96,29 @@ func CheckPushPermissions(opts *config.KanikoOptions) error {
 	return nil
 }
 
+func getDigest(image v1.Image) ([]byte, error) {
+	digest, err := image.Digest()
+	if err != nil {
+		return nil, err
+	}
+	return []byte(digest.String()), nil
+}
+
 // DoPush is responsible for pushing image to the destinations specified in opts
 func DoPush(image v1.Image, opts *config.KanikoOptions) error {
 	t := timing.Start("Total Push Time")
-
-	if opts.DigestFile != "" {
-		digest, err := image.Digest()
+	var digestByteArray []byte
+	var builder strings.Builder
+	if opts.DigestFile != "" || opts.ImageNameDigestFile != "" {
+		var err error
+		digestByteArray, err = getDigest(image)
 		if err != nil {
 			return errors.Wrap(err, "error fetching digest")
 		}
-		digestByteArray := []byte(digest.String())
-		err = ioutil.WriteFile(opts.DigestFile, digestByteArray, 0644)
+	}
+
+	if opts.DigestFile != "" {
+		err := ioutil.WriteFile(opts.DigestFile, digestByteArray, 0644)
 		if err != nil {
 			return errors.Wrap(err, "writing digest to file failed")
 		}
@@ -128,9 +140,21 @@ func DoPush(image v1.Image, opts *config.KanikoOptions) error {
 		if err != nil {
 			return errors.Wrap(err, "getting tag for destination")
 		}
+		if opts.ImageNameDigestFile != "" {
+			imageName := []byte(destRef.Repository.Name() + "@")
+			builder.Write(append(imageName, digestByteArray...))
+			builder.WriteString("\n")
+		}
 		destRefs = append(destRefs, destRef)
 	}
 
+	if opts.ImageNameDigestFile != "" {
+		err := ioutil.WriteFile(opts.ImageNameDigestFile, []byte(builder.String()), 0644)
+		if err != nil {
+			return errors.Wrap(err, "writing digest to file failed")
+		}
+	}
+
 	if opts.TarPath != "" {
 		tagToImage := map[name.Tag]v1.Image{}
 		for _, destRef := range destRefs {

pkg/executor/push_test.go

@@ -192,3 +192,34 @@ func TestOCILayoutPath(t *testing.T) {
 	got, err := layoutImage.Manifest()
 	testutil.CheckErrorAndDeepEqual(t, false, err, want, got)
 }
+
+func TestImageNameDigestFile(t *testing.T) {
+	image, err := random.Image(1024, 4)
+	if err != nil {
+		t.Fatalf("could not create image: %s", err)
+	}
+
+	digest, err := image.Digest()
+	if err != nil {
+		t.Fatalf("could not get image digest: %s", err)
+	}
+
+	opts := config.KanikoOptions{
+		NoPush:              true,
+		Destinations:        []string{"gcr.io/foo/bar:latest", "bob/image"},
+		ImageNameDigestFile: "tmpFile",
+	}
+
+	defer os.Remove("tmpFile")
+
+	if err := DoPush(image, &opts); err != nil {
+		t.Fatalf("could not push image: %s", err)
+	}
+
+	want := []byte("gcr.io/foo/bar@" + digest.String() + "\nindex.docker.io/bob/image@" + digest.String() + "\n")
+
+	got, err := ioutil.ReadFile("tmpFile")
+
+	testutil.CheckErrorAndDeepEqual(t, false, err, want, got)
+
+}