Merge pull request #362 from tonistiigi/labels

dockerfile: add test for labels

frontend/dockerfile/builder/build.go

@@ -24,6 +24,7 @@ const (
 	defaultDockerfileName = "Dockerfile"
 	dockerignoreFilename  = ".dockerignore"
 	buildArgPrefix        = "build-arg:"
+	labelPrefix           = "label:"
 	gitPrefix             = "git://"
 )
 
@@ -103,7 +104,8 @@ func Build(ctx context.Context, c client.Client) error {
 	st, img, err := dockerfile2llb.Dockerfile2LLB(ctx, dtDockerfile, dockerfile2llb.ConvertOpt{
 		Target:       opts[keyTarget],
 		MetaResolver: c,
-		BuildArgs:    filterBuildArgs(opts),
+		BuildArgs:    filter(opts, buildArgPrefix),
+		Labels:       filter(opts, labelPrefix),
 		SessionID:    c.SessionID(),
 		BuildContext: buildContext,
 		Excludes:     excludes,
@@ -132,11 +134,11 @@ func Build(ctx context.Context, c client.Client) error {
 	return nil
 }
 
-func filterBuildArgs(opt map[string]string) map[string]string {
+func filter(opt map[string]string, key string) map[string]string {
 	m := map[string]string{}
 	for k, v := range opt {
-		if strings.HasPrefix(k, buildArgPrefix) {
-			m[strings.TrimPrefix(k, buildArgPrefix)] = v
+		if strings.HasPrefix(k, key) {
+			m[strings.TrimPrefix(k, key)] = v
 		}
 	}
 	return m

frontend/dockerfile/dockerfile2llb/convert.go

@@ -36,6 +36,7 @@ type ConvertOpt struct {
 	Target       string
 	MetaResolver llb.ImageMetaResolver
 	BuildArgs    map[string]string
+	Labels       map[string]string
 	SessionID    string
 	BuildContext *llb.State
 	Excludes     []string
@@ -226,6 +227,10 @@ func Dockerfile2LLB(ctx context.Context, dt []byte, opt ConvertOpt) (*llb.State,
 		}
 	}
 
+	for k, v := range opt.Labels {
+		target.image.Config.Labels[k] = v
+	}
+
 	opts := []llb.LocalOption{
 		llb.SessionID(opt.SessionID),
 		llb.ExcludePatterns(opt.Excludes),

frontend/dockerfile/dockerfile_test.go

@@ -51,6 +51,7 @@ func TestIntegration(t *testing.T) {
 		testMultiStageImplicitFrom,
 		testCopyVarSubstitution,
 		testMultiStageCaseInsensitive,
+		testLabels,
 	})
 }
 
@@ -1195,6 +1196,81 @@ COPY --from=stage1 baz bax
 	require.Contains(t, string(dt), "foo-contents")
 }
 
+func testLabels(t *testing.T, sb integration.Sandbox) {
+	t.Parallel()
+
+	dockerfile := []byte(`
+FROM scratch
+LABEL foo=bar
+`)
+	dir, err := tmpdir(
+		fstest.CreateFile("Dockerfile", dockerfile, 0600),
+	)
+	require.NoError(t, err)
+	defer os.RemoveAll(dir)
+
+	c, err := client.New(sb.Address())
+	require.NoError(t, err)
+	defer c.Close()
+
+	destDir, err := ioutil.TempDir("", "buildkit")
+	require.NoError(t, err)
+	defer os.RemoveAll(destDir)
+
+	target := "example.com/moby/dockerfilelabels:test"
+	err = c.Solve(context.TODO(), nil, client.SolveOpt{
+		Frontend: "dockerfile.v0",
+		FrontendAttrs: map[string]string{
+			"label:bar": "baz",
+		},
+		Exporter: client.ExporterImage,
+		ExporterAttrs: map[string]string{
+			"name": target,
+		},
+		LocalDirs: map[string]string{
+			builder.LocalNameDockerfile: dir,
+			builder.LocalNameContext:    dir,
+		},
+	}, nil)
+	require.NoError(t, err)
+
+	var cdAddress string
+	if cd, ok := sb.(interface {
+		ContainerdAddress() string
+	}); !ok {
+		t.Skip("only for containerd worker")
+	} else {
+		cdAddress = cd.ContainerdAddress()
+	}
+
+	client, err := containerd.New(cdAddress)
+	require.NoError(t, err)
+	defer client.Close()
+
+	ctx := namespaces.WithNamespace(context.Background(), "buildkit")
+
+	img, err := client.ImageService().Get(ctx, target)
+	require.NoError(t, err)
+
+	desc, err := img.Config(ctx, client.ContentStore(), platforms.Default())
+	require.NoError(t, err)
+
+	dt, err := content.ReadBlob(ctx, client.ContentStore(), desc.Digest)
+	require.NoError(t, err)
+
+	var ociimg ocispec.Image
+	err = json.Unmarshal(dt, &ociimg)
+	require.NoError(t, err)
+
+	v, ok := ociimg.Config.Labels["foo"]
+	require.True(t, ok)
+	require.Equal(t, v, "bar")
+
+	v, ok = ociimg.Config.Labels["bar"]
+	require.True(t, ok)
+	require.Equal(t, v, "baz")
+}
+
 func tmpdir(appliers ...fstest.Applier) (string, error) {
 	tmpdir, err := ioutil.TempDir("", "buildkit-dockerfile")
 	if err != nil {