feat(distribution): add CNCF ModelPack format compatibility

pkg/distribution/distribution/client.go

@@ -14,6 +14,7 @@ import (
 
 	"github.com/docker/model-runner/pkg/distribution/internal/progress"
 	"github.com/docker/model-runner/pkg/distribution/internal/store"
+	"github.com/docker/model-runner/pkg/distribution/modelpack"
 	"github.com/docker/model-runner/pkg/distribution/registry"
 	"github.com/docker/model-runner/pkg/distribution/tarball"
 	"github.com/docker/model-runner/pkg/distribution/types"
@@ -213,11 +214,22 @@ func (c *Client) PullModel(ctx context.Context, reference string, progressWriter
 		}
 	}
 
-	// Check for supported type
-	if err := checkCompat(remoteModel, c.log, reference, progressWriter); err != nil {
+	// Check for supported type and convert ModelPack format if needed
+	remoteModel, err = checkAndConvertCompat(remoteModel, c.log, reference, progressWriter)
+	if err != nil {
 		return err
 	}
 
+	// Update digest after potential conversion (ModelPack conversion changes the manifest)
+	convertedDigest, err := remoteModel.Digest()
+	if err != nil {
+		return fmt.Errorf("getting converted model digest: %w", err)
+	}
+	if convertedDigest != remoteDigest {
+		c.log.Infof("Model converted from ModelPack format, new digest: %s", convertedDigest.String())
+	}
+	remoteDigest = convertedDigest
+
 	// Check if model exists in local store
 	localModel, err := c.store.Read(remoteDigest.String())
 	if err == nil {
@@ -474,19 +486,38 @@ func GetSupportedFormats() []types.Format {
 	return []types.Format{types.FormatGGUF}
 }
 
-func checkCompat(image types.ModelArtifact, log *logrus.Entry, reference string, progressWriter io.Writer) error {
+// checkAndConvertCompat validates model compatibility.
+// Both Docker format and CNCF ModelPack format are supported.
+// ModelPack format is stored as-is and converted at read time.
+func checkAndConvertCompat(image types.ModelArtifact, log *logrus.Entry, reference string, progressWriter io.Writer) (types.ModelArtifact, error) {
 	manifest, err := image.Manifest()
 	if err != nil {
-		return err
+		return nil, err
+	}
+
+	mediaTypeStr := string(manifest.Config.MediaType)
+
+	// 檢查是不是支援的格式（Docker 或 ModelPack）
+	isDocker := mediaTypeStr == string(types.MediaTypeModelConfigV01)
+	isModelPack := modelpack.IsModelPackMediaType(mediaTypeStr)
+
+	if !isDocker && !isModelPack {
+		return nil, fmt.Errorf("config type %q is unsupported: %w", mediaTypeStr, ErrUnsupportedMediaType)
 	}
-	if manifest.Config.MediaType != types.MediaTypeModelConfigV01 {
-		return fmt.Errorf("config type %q is unsupported: %w", manifest.Config.MediaType, ErrUnsupportedMediaType)
+
+	// ModelPack 格式會原封不動儲存，讀取時再轉換
+	if isModelPack {
+		log.Infof("Detected ModelPack format for %s (stored as-is)",
+			utils.SanitizeForLog(reference))
+		if err := progress.WriteInfo(progressWriter, "ModelPack format detected"); err != nil {
+			log.Warnf("Failed to write info message: %v", err)
+		}
 	}
 
 	// Check if the model format is supported
 	config, err := image.Config()
 	if err != nil {
-		return fmt.Errorf("reading model config: %w", err)
+		return nil, fmt.Errorf("reading model config: %w", err)
 	}
 
 	if config.Format == "" {
@@ -501,5 +532,5 @@ func checkCompat(image types.ModelArtifact, log *logrus.Entry, reference string,
 		// Don't return an error - allow the pull to continue
 	}
 
-	return nil
+	return image, nil
 }

pkg/distribution/internal/partial/partial.go

@@ -8,6 +8,7 @@ import (
 	"github.com/docker/model-runner/pkg/go-containerregistry/pkg/v1/partial"
 	ggcr "github.com/docker/model-runner/pkg/go-containerregistry/pkg/v1/types"
 
+	"github.com/docker/model-runner/pkg/distribution/modelpack"
 	"github.com/docker/model-runner/pkg/distribution/types"
 )
 
@@ -21,9 +22,15 @@ func ConfigFile(i WithRawConfigFile) (*types.ConfigFile, error) {
 	if err != nil {
 		return nil, fmt.Errorf("get raw config file: %w", err)
 	}
+
+	// 自動偵測 ModelPack 格式，讀取時轉換成 Docker 格式
+	if modelpack.IsModelPackConfig(raw) {
+		return modelpack.ConvertToDockerConfig(raw)
+	}
+
 	var cf types.ConfigFile
 	if err := json.Unmarshal(raw, &cf); err != nil {
-		return nil, fmt.Errorf("unmarshal : %w", err)
+		return nil, fmt.Errorf("unmarshal config: %w", err)
 	}
 	return &cf, nil
 }
@@ -127,7 +134,12 @@ func layerPathsByMediaType(i WithLayers, mediaType ggcr.MediaType) ([]string, er
 	var paths []string
 	for _, l := range layers {
 		mt, err := l.MediaType()
-		if err != nil || mt != mediaType {
+		if err != nil {
+			continue
+		}
+		// 把 ModelPack 的媒體類型轉成 Docker 格式再比對
+		mappedMT := ggcr.MediaType(modelpack.MapLayerMediaType(string(mt)))
+		if mappedMT != mediaType {
 			continue
 		}
 		layer, ok := l.(*Layer)

pkg/distribution/internal/partial/partial_test.go

@@ -8,8 +8,76 @@ import (
 	"github.com/docker/model-runner/pkg/distribution/internal/mutate"
 	"github.com/docker/model-runner/pkg/distribution/internal/partial"
 	"github.com/docker/model-runner/pkg/distribution/types"
+	ggcr "github.com/docker/model-runner/pkg/go-containerregistry/pkg/v1/types"
 )
 
+// mockConfig 用來測試 ConfigFile 函數
+type mockConfig struct {
+	raw []byte
+	err error
+}
+
+func (m *mockConfig) RawConfigFile() ([]byte, error) {
+	return m.raw, m.err
+}
+
+// TestConfigFile_AutoDetection 測試 ConfigFile 能自動偵測並轉換 ModelPack 格式
+func TestConfigFile_AutoDetection(t *testing.T) {
+	t.Run("Docker format passes through", func(t *testing.T) {
+		// Docker 格式的 config
+		dockerJSON := `{
+			"config": {"format": "gguf", "parameters": "8B"},
+			"descriptor": {},
+			"rootfs": {"type": "layers", "diff_ids": []}
+		}`
+
+		mock := &mockConfig{raw: []byte(dockerJSON)}
+		cf, err := partial.ConfigFile(mock)
+		if err != nil {
+			t.Fatalf("ConfigFile() error = %v", err)
+		}
+
+		if cf.Config.Format != types.FormatGGUF {
+			t.Errorf("Format = %v, want %v", cf.Config.Format, types.FormatGGUF)
+		}
+		if cf.Config.Parameters != "8B" {
+			t.Errorf("Parameters = %q, want %q", cf.Config.Parameters, "8B")
+		}
+	})
+
+	t.Run("ModelPack format auto-converts", func(t *testing.T) {
+		// ModelPack 格式的 config（用 paramSize 不是 parameters）
+		modelPackJSON := `{
+			"descriptor": {"createdAt": "2025-01-15T10:30:00Z"},
+			"config": {"format": "gguf", "paramSize": "8B"},
+			"modelfs": {"type": "layers", "diffIds": []}
+		}`
+
+		mock := &mockConfig{raw: []byte(modelPackJSON)}
+		cf, err := partial.ConfigFile(mock)
+		if err != nil {
+			t.Fatalf("ConfigFile() error = %v", err)
+		}
+
+		// 轉換後應該要有 Docker 格式的欄位
+		if cf.Config.Format != types.FormatGGUF {
+			t.Errorf("Format = %v, want %v", cf.Config.Format, types.FormatGGUF)
+		}
+		// paramSize 應該被轉成 parameters
+		if cf.Config.Parameters != "8B" {
+			t.Errorf("Parameters = %q, want %q", cf.Config.Parameters, "8B")
+		}
+	})
+
+	t.Run("invalid JSON returns error", func(t *testing.T) {
+		mock := &mockConfig{raw: []byte("not valid json")}
+		_, err := partial.ConfigFile(mock)
+		if err == nil {
+			t.Error("expected error for invalid JSON")
+		}
+	})
+}
+
 func TestMMPROJPath(t *testing.T) {
 	// Create a model from GGUF file
 	mdl, err := gguf.NewModel(filepath.Join("..", "..", "assets", "dummy.gguf"))
@@ -122,3 +190,33 @@ func TestLayerPathByMediaType(t *testing.T) {
 	}
 
 }
+
+// TestGGUFPaths_ModelPackMediaType 測試 GGUFPaths 能找到 ModelPack 格式的層
+func TestGGUFPaths_ModelPackMediaType(t *testing.T) {
+	// 用 ModelPack 的 GGUF 媒體類型建立層
+	modelPackGGUFType := ggcr.MediaType("application/vnd.cncf.model.weight.v1.gguf")
+
+	layer, err := partial.NewLayer(filepath.Join("..", "..", "assets", "dummy.gguf"), modelPackGGUFType)
+	if err != nil {
+		t.Fatalf("建立 ModelPack 層失敗: %v", err)
+	}
+
+	// 用 mutate 建立含有這個層的 model
+	mdl, err := gguf.NewModel(filepath.Join("..", "..", "assets", "dummy.gguf"))
+	if err != nil {
+		t.Fatalf("建立 GGUF model 失敗: %v", err)
+	}
+
+	mdlWithModelPackLayer := mutate.AppendLayers(mdl, layer)
+
+	// GGUFPaths 應該要能找到 ModelPack 格式的 GGUF 層
+	paths, err := partial.GGUFPaths(mdlWithModelPackLayer)
+	if err != nil {
+		t.Fatalf("GGUFPaths() error = %v", err)
+	}
+
+	// 應該找到兩個：原本的 Docker 格式 + 新加的 ModelPack 格式
+	if len(paths) != 2 {
+		t.Errorf("預期找到 2 個 GGUF 路徑, 實際找到 %d 個", len(paths))
+	}
+}

pkg/distribution/internal/progress/reporter.go

@@ -139,6 +139,14 @@ func WriteProgress(w io.Writer, msg string, imageSize, layerSize, current uint64
 	})
 }
 
+// WriteInfo writes an info message
+func WriteInfo(w io.Writer, message string) error {
+	return write(w, Message{
+		Type:    "info",
+		Message: message,
+	})
+}
+
 // WriteSuccess writes a success message
 func WriteSuccess(w io.Writer, message string) error {
 	return write(w, Message{