fix unpacking multi-target builds

+ split out digest file creation, rename some vars

closes #9

Co-authored-by: Taylor Silva <[email protected]>
Signed-off-by: Alex Suraci <[email protected]>

task.go

@@ -26,7 +26,6 @@ func Build(buildkitd *Buildkitd, outputsDir string, req Request) (Response, erro
 		return Response{}, errors.Wrap(err, "config")
 	}
 
-	imageDir := filepath.Join(outputsDir, "image")
 	cacheDir := filepath.Join(outputsDir, "cache")
 
 	res := Response{
@@ -67,9 +66,7 @@ func Build(buildkitd *Buildkitd, outputsDir string, req Request) (Response, erro
 	var imagePaths []string
 
 	for _, t := range cfg.AdditionalTargets {
-		targetArgs := make([]string, len(buildctlArgs))
-		copy(targetArgs, buildctlArgs)
-		targetArgs = append(targetArgs, "--opt", "target="+t)
+		targetArgs := append(buildctlArgs, "--opt", "target="+t)
 
 		targetDir := filepath.Join(outputsDir, t)
 
@@ -85,8 +82,9 @@ func Build(buildkitd *Buildkitd, outputsDir string, req Request) (Response, erro
 		builds = append(builds, targetArgs)
 	}
 
-	if _, err := os.Stat(imageDir); err == nil {
-		imagePath := filepath.Join(imageDir, "image.tar")
+	finalTargetDir := filepath.Join(outputsDir, "image")
+	if _, err := os.Stat(finalTargetDir); err == nil {
+		imagePath := filepath.Join(finalTargetDir, "image.tar")
 		imagePaths = append(imagePaths, imagePath)
 
 		buildctlArgs = append(buildctlArgs,
@@ -120,25 +118,20 @@ func Build(buildkitd *Buildkitd, outputsDir string, req Request) (Response, erro
 	}
 
 	for _, imagePath := range imagePaths {
-		digestPath := filepath.Join(filepath.Dir(imagePath), "digest")
-
 		image, err := tarball.ImageFromPath(imagePath, nil)
 		if err != nil {
 			return Response{}, errors.Wrap(err, "open oci image")
 		}
 
-		manifest, err := image.Manifest()
-		if err != nil {
-			return Response{}, errors.Wrap(err, "get image digest")
-		}
+		outputDir := filepath.Dir(imagePath)
 
-		err = ioutil.WriteFile(digestPath, []byte(manifest.Config.Digest.String()), 0644)
+		err = writeDigest(outputDir, image)
 		if err != nil {
-			return Response{}, errors.Wrap(err, "write digest")
+			return Response{}, err
 		}
 
 		if req.Config.UnpackRootfs {
-			err = unpackRootfs(imageDir, image, cfg)
+			err = unpackRootfs(outputDir, image, cfg)
 			if err != nil {
 				return Response{}, errors.Wrap(err, "unpack rootfs")
 			}
@@ -148,6 +141,22 @@ func Build(buildkitd *Buildkitd, outputsDir string, req Request) (Response, erro
 	return res, nil
 }
 
+func writeDigest(dest string, image v1.Image) error {
+	digestPath := filepath.Join(dest, "digest")
+
+	manifest, err := image.Manifest()
+	if err != nil {
+		return errors.Wrap(err, "get image digest")
+	}
+
+	err = ioutil.WriteFile(digestPath, []byte(manifest.Config.Digest.String()), 0644)
+	if err != nil {
+		return errors.Wrap(err, "write digest file")
+	}
+
+	return nil
+}
+
 func unpackRootfs(dest string, image v1.Image, cfg Config) error {
 	rootfsDir := filepath.Join(dest, "rootfs")
 	metadataPath := filepath.Join(dest, "metadata.json")

task_test.go

@@ -153,7 +153,7 @@ func (s *TaskSuite) TestBuildArgsStaticAndFile() {
 func (s *TaskSuite) TestLabels() {
 	s.req.Config.ContextDir = "testdata/labels"
 	expectedLabels := map[string]string{
-		"some_label": "some_value",
+		"some_label":       "some_value",
 		"some_other_label": "some_other_value",
 	}
 	s.req.Config.Labels = make([]string, 0, len(expectedLabels))
@@ -177,7 +177,7 @@ func (s *TaskSuite) TestLabels() {
 func (s *TaskSuite) TestLabelsFile() {
 	s.req.Config.ContextDir = "testdata/labels"
 	expectedLabels := map[string]string{
-		"some_label": "some_value",
+		"some_label":       "some_value",
 		"some_other_label": "some_other_value",
 	}
 	s.req.Config.LabelsFile = "testdata/labels/labels_file"
@@ -198,9 +198,9 @@ func (s *TaskSuite) TestLabelsStaticAndFileAndLayer() {
 	s.req.Config.ContextDir = "testdata/labels"
 	s.req.Config.DockerfilePath = "testdata/labels/label_layer.dockerfile"
 	expectedLabels := map[string]string{
-		"some_label": "some_value",
+		"some_label":       "some_value",
 		"some_other_label": "some_other_value",
-		"label_layer": "some_label_layer_value",
+		"label_layer":      "some_label_layer_value",
 	}
 	s.req.Config.Labels = []string{"some_label=some_value"}
 	s.req.Config.LabelsFile = "testdata/labels/label_file"
@@ -224,7 +224,7 @@ func (s *TaskSuite) TestUnpackRootfs() {
 	_, err := s.build()
 	s.NoError(err)
 
-	meta, err := s.imageMetadata()
+	meta, err := s.imageMetadata("image")
 	s.NoError(err)
 
 	rootfsContent, err := ioutil.ReadFile(s.imagePath("rootfs", "Dockerfile"))
@@ -317,14 +317,67 @@ func (s *TaskSuite) TestMultiTarget() {
 	additionalCfg, err := additionalImage.ConfigFile()
 	s.NoError(err)
 	s.Equal("additional-target", additionalCfg.Config.Labels["target"])
+}
 
-	digest, err := ioutil.ReadFile(s.outputPath("additional-target", "digest"))
+func (s *TaskSuite) TestMultiTargetDigest() {
+	s.req.Config.ContextDir = "testdata/multi-target"
+	s.req.Config.AdditionalTargets = []string{"additional-target"}
+
+	err := os.Mkdir(s.outputPath("additional-target"), 0755)
 	s.NoError(err)
 
-	additionalManifest, err := additionalImage.Manifest()
+	_, err = s.build()
 	s.NoError(err)
 
+	additionalImage, err := tarball.ImageFromPath(s.outputPath("additional-target", "image.tar"), nil)
+	s.NoError(err)
+	digest, err := ioutil.ReadFile(s.outputPath("additional-target", "digest"))
+	s.NoError(err)
+	additionalManifest, err := additionalImage.Manifest()
+	s.NoError(err)
 	s.Equal(string(digest), additionalManifest.Config.Digest.String())
+
+	finalImage, err := tarball.ImageFromPath(s.imagePath("image.tar"), nil)
+	s.NoError(err)
+	digest, err = ioutil.ReadFile(s.outputPath("image", "digest"))
+	s.NoError(err)
+	finalManifest, err := finalImage.Manifest()
+	s.NoError(err)
+	s.Equal(string(digest), finalManifest.Config.Digest.String())
+}
+
+func (s *TaskSuite) TestMultiTargetUnpack() {
+	s.req.Config.ContextDir = "testdata/multi-target"
+	s.req.Config.AdditionalTargets = []string{"additional-target"}
+	s.req.Config.UnpackRootfs = true
+
+	err := os.Mkdir(s.outputPath("additional-target"), 0755)
+	s.NoError(err)
+
+	_, err = s.build()
+	s.NoError(err)
+
+	rootfsContent, err := ioutil.ReadFile(s.outputPath("additional-target", "rootfs", "Dockerfile.banana"))
+	s.NoError(err)
+	expectedContent, err := ioutil.ReadFile("testdata/multi-target/Dockerfile")
+	s.NoError(err)
+	s.Equal(rootfsContent, expectedContent)
+
+	meta, err := s.imageMetadata("additional-target")
+	s.NoError(err)
+	s.Equal(meta.User, "banana")
+	s.Equal(meta.Env, []string{"PATH=/darkness", "BA=nana"})
+
+	rootfsContent, err = ioutil.ReadFile(s.outputPath("image", "rootfs", "Dockerfile.orange"))
+	s.NoError(err)
+	expectedContent, err = ioutil.ReadFile("testdata/multi-target/Dockerfile")
+	s.NoError(err)
+	s.Equal(rootfsContent, expectedContent)
+
+	meta, err = s.imageMetadata("image")
+	s.NoError(err)
+	s.Equal(meta.User, "orange")
+	s.Equal(meta.Env, []string{"PATH=/lightness", "OR=ange"})
 }
 
 func (s *TaskSuite) build() (task.Response, error) {
@@ -339,8 +392,8 @@ func (s *TaskSuite) outputPath(path ...string) string {
 	return filepath.Join(append([]string{s.outputsDir}, path...)...)
 }
 
-func (s *TaskSuite) imageMetadata() (task.ImageMetadata, error) {
-	metadataPayload, err := ioutil.ReadFile(s.imagePath("metadata.json"))
+func (s *TaskSuite) imageMetadata(output string) (task.ImageMetadata, error) {
+	metadataPayload, err := ioutil.ReadFile(s.outputPath(output, "metadata.json"))
 	if err != nil {
 		return task.ImageMetadata{}, err
 	}

testdata/multi-target/Dockerfile

@@ -1,8 +1,13 @@
-FROM busybox
-RUN false
-
-FROM busybox AS additional-target
+FROM scratch AS additional-target
 LABEL target=additional-target
+USER banana
+ADD Dockerfile /Dockerfile.banana
+ENV PATH=/darkness
+ENV BA=nana
 
-FROM busybox
+FROM scratch
 LABEL target=final-target
+USER orange
+ADD Dockerfile /Dockerfile.orange
+ENV PATH=/lightness
+ENV OR=ange