refactor: replace deprecated WithConfigMediaType with WithManifestOptions and clean up related code

Author: ilopezluna

pkg/distribution/builder/builder.go

@@ -7,14 +7,13 @@ import (
 	"io"
 	"time"
 
-	"github.com/opencontainers/go-digest"
-
 	"github.com/docker/model-runner/pkg/distribution/format"
 	"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/modelpack"
 	"github.com/docker/model-runner/pkg/distribution/oci"
 	"github.com/docker/model-runner/pkg/distribution/types"
+	"github.com/opencontainers/go-digest"
 )
 
 // BuildFormat specifies the output artifact format.

pkg/distribution/builder/from_directory.go

@@ -8,15 +8,14 @@ import (
 	"strings"
 	"time"
 
-	"github.com/opencontainers/go-digest"
-
 	"github.com/docker/model-runner/pkg/distribution/files"
 	"github.com/docker/model-runner/pkg/distribution/format"
 	"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/modelpack"
 	"github.com/docker/model-runner/pkg/distribution/oci"
 	"github.com/docker/model-runner/pkg/distribution/types"
+	"github.com/opencontainers/go-digest"
 )
 
 const rootFSType = "rootfs"

pkg/distribution/internal/mutate/model.go

@@ -109,8 +109,6 @@ func (m *model) GetManifestOptions() partial.ManifestOptions {
 	var opts partial.ManifestOptions
 	if base, ok := m.base.(partial.WithManifestOptions); ok {
 		opts = base.GetManifestOptions()
-	} else if cmt, ok := m.base.(partial.WithConfigMediaType); ok {
-		opts.ConfigMediaType = cmt.GetConfigMediaType()
 	}
 	// Apply overrides set on this wrapper.
 	if m.configMediaType != "" {

pkg/distribution/internal/partial/cncf_model.go

@@ -31,11 +31,6 @@ func (m *CNCFModel) GetManifestOptions() ManifestOptions {
 	}
 }
 
-// GetConfigMediaType implements WithConfigMediaType for backward compatibility.
-func (m *CNCFModel) GetConfigMediaType() oci.MediaType {
-	return modelpack.MediaTypeModelConfigV1
-}
-
 func (m *CNCFModel) Layers() ([]oci.Layer, error) {
 	return m.LayerList, nil
 }

pkg/distribution/internal/partial/model.go

@@ -130,8 +130,11 @@ func (m *BaseModel) Descriptor() (types.Descriptor, error) {
 	return Descriptor(m)
 }
 
-// GetConfigMediaType returns the config media type for the model.
-// If not set, returns empty string and ManifestForLayers will default to V0.1.
-func (m *BaseModel) GetConfigMediaType() oci.MediaType {
-	return m.ConfigMediaType
+// GetManifestOptions implements WithManifestOptions, providing the config
+// media type for Docker-format models. If ConfigMediaType is not set,
+// ManifestForLayers will default to V0.1.
+func (m *BaseModel) GetManifestOptions() ManifestOptions {
+	return ManifestOptions{
+		ConfigMediaType: m.ConfigMediaType,
+	}
 }

pkg/distribution/internal/partial/partial.go

@@ -301,12 +301,6 @@ func matchesMediaType(layerMT, targetMT oci.MediaType, modelFormat string) bool
 	return false
 }
 
-// WithConfigMediaType provides access to the config media type version.
-// Deprecated: prefer WithManifestOptions which also carries the artifact type.
-type WithConfigMediaType interface {
-	GetConfigMediaType() oci.MediaType
-}
-
 // ManifestOptions holds the manifest-level metadata for an artifact.
 type ManifestOptions struct {
 	// ConfigMediaType is the media type of the config blob.
@@ -317,29 +311,23 @@ type ManifestOptions struct {
 	ArtifactType string
 }
 
-// WithManifestOptions provides manifest assembly options. It takes precedence
-// over WithConfigMediaType when both are implemented.
+// WithManifestOptions provides manifest assembly options.
 type WithManifestOptions interface {
 	GetManifestOptions() ManifestOptions
 }
 
-// resolveManifestOptions extracts manifest options from the given object,
-// checking WithManifestOptions first and falling back to WithConfigMediaType.
+// resolveManifestOptions extracts manifest options from the given object
+// via the WithManifestOptions interface.
 func resolveManifestOptions(i interface{}) ManifestOptions {
 	if mof, ok := i.(WithManifestOptions); ok {
 		return mof.GetManifestOptions()
 	}
-	if cmt, ok := i.(WithConfigMediaType); ok {
-		if mt := cmt.GetConfigMediaType(); mt != "" {
-			return ManifestOptions{ConfigMediaType: mt}
-		}
-	}
 	return ManifestOptions{}
 }
 
 // ManifestForLayers assembles an OCI manifest for the given model. The
 // config media type and optional artifact type are read from the model via
-// the WithManifestOptions interface (or the legacy WithConfigMediaType).
+// the WithManifestOptions interface.
 func ManifestForLayers(i WithLayers) (*oci.Manifest, error) {
 	raw, err := i.RawConfigFile()
 	if err != nil {

pkg/distribution/internal/testutil/model.go

@@ -143,10 +143,13 @@ func NewModelPackArtifact(t *testing.T, model modelpack.Model, layers ...LayerSp
 	return NewArtifact(rawConfig, modelpack.MediaTypeModelConfigV1, builtLayers...)
 }
 
-// GetConfigMediaType implements partial.WithConfigMediaType so that ManifestForLayers
-// uses the correct config media type when building the OCI manifest.
-func (a *Artifact) GetConfigMediaType() oci.MediaType {
-	return a.configMediaType
+// GetManifestOptions implements partial.WithManifestOptions so that
+// ManifestForLayers uses the correct config media type when building the
+// OCI manifest.
+func (a *Artifact) GetManifestOptions() partial.ManifestOptions {
+	return partial.ManifestOptions{
+		ConfigMediaType: a.configMediaType,
+	}
 }
 
 // ID implements types.ModelArtifact.

pkg/distribution/modelpack/convert.go

@@ -32,7 +32,7 @@ const (
 //  2. Filepath/annotation heuristics for ambiguous media types.
 //  3. Docker media type fallback.
 func ClassifyLayer(dockerMT oci.MediaType, path string) LayerKind {
-	switch dockerMT {
+	switch dockerMT { //nolint:exhaustive // Only Docker semantic media types are classified; OCI standard types fall through to filepath heuristics.
 	case types.MediaTypeLicense:
 		return KindDoc
 	case types.MediaTypeChatTemplate, types.MediaTypeVLLMConfigArchive, types.MediaTypeModelFile:
@@ -62,6 +62,8 @@ func classifyByPath(path string) LayerKind {
 		return KindDoc
 	case files.FileTypeChatTemplate:
 		return KindWeightConfig
+	case files.FileTypeUnknown:
+		return KindWeightConfig
 	case files.FileTypeConfig:
 		// .md files are documentation, not weight config.
 		if strings.ToLower(filepath.Ext(path)) == ".md" {
@@ -80,9 +82,10 @@ func LayerKindToMediaType(kind LayerKind) oci.MediaType {
 		return MediaTypeWeightRaw
 	case KindDoc:
 		return MediaTypeDocRaw
-	default:
+	case KindWeightConfig:
 		return MediaTypeWeightConfigRaw
 	}
+	return MediaTypeWeightConfigRaw
 }
 
 // MapLayerMediaType returns the CNCF model-spec media type for the given

pkg/distribution/modelpack/types.go

@@ -3,22 +3,20 @@
 // without conversion. Both Docker and ModelPack formats are supported natively through
 // the types.ModelConfig interface.
 //
-// Note: JSON tags in this package use camelCase (e.g., "createdAt", "paramSize") to match
-// the CNCF ModelPack spec, which differs from Docker model-spec's snake_case convention
-// (e.g., "context_size").
+// The struct types (ModelDescriptor, ModelConfig, ModelFS, ModelCapabilities) are
+// re-exported directly from the official CNCF model-spec Go module so that
+// serialization tags and field definitions stay in sync with the specification.
 //
 // See: https://github.com/modelpack/model-spec
 package modelpack
 
 import (
 	"encoding/json"
 	"strings"
-	"time"
 
 	"github.com/docker/model-runner/pkg/distribution/types"
-	"github.com/opencontainers/go-digest"
-
 	specv1 "github.com/modelpack/model-spec/specs-go/v1"
+	"github.com/opencontainers/go-digest"
 )
 
 const (
@@ -60,6 +58,40 @@ const (
 	MediaTypeWeightSafetensors = "application/vnd.cncf.model.weight.v1.safetensors"
 )
 
+// Type aliases re-export the canonical CNCF model-spec struct types so that
+// callers use the upstream definitions (and their JSON tags) by default.
+// This eliminates local struct duplication while keeping the modelpack
+// package as the single import for DMR code.
+type (
+	// ModelDescriptor defines the general information of a model.
+	ModelDescriptor = specv1.ModelDescriptor
+
+	// ModelConfig defines the execution parameters for an inference engine.
+	ModelConfig = specv1.ModelConfig
+
+	// ModelFS describes the layer content addresses.
+	ModelFS = specv1.ModelFS
+
+	// ModelCapabilities defines the special capabilities that the model supports.
+	ModelCapabilities = specv1.ModelCapabilities
+)
+
+// Model represents the CNCF ModelPack config structure.
+// It provides the `application/vnd.cncf.model.config.v1+json` mediatype when marshalled to JSON.
+//
+// The struct mirrors specv1.Model but is declared as its own named type so
+// that it can implement the types.ModelConfig interface required by DMR.
+type Model struct {
+	// Descriptor provides metadata about the model provenance and identity.
+	Descriptor ModelDescriptor `json:"descriptor"`
+
+	// ModelFS describes the layer content addresses.
+	ModelFS ModelFS `json:"modelfs"`
+
+	// Config defines the execution parameters for the model.
+	Config ModelConfig `json:"config,omitempty"`
+}
+
 // IsModelPackWeightMediaType checks if the given media type is a CNCF ModelPack weight layer type.
 // This includes both format-specific types (e.g., .gguf, .safetensors) and
 // format-agnostic types from the official model-spec (e.g., .raw, .tar).
@@ -126,121 +158,6 @@ func IsModelPackConfig(raw []byte) bool {
 	return false
 }
 
-// Model represents the CNCF ModelPack config structure.
-// It provides the `application/vnd.cncf.model.config.v1+json` mediatype when marshalled to JSON.
-type Model struct {
-	// Descriptor provides metadata about the model provenance and identity.
-	Descriptor ModelDescriptor `json:"descriptor"`
-
-	// ModelFS describes the layer content addresses.
-	ModelFS ModelFS `json:"modelfs"`
-
-	// Config defines the execution parameters for the model.
-	Config ModelConfig `json:"config,omitempty"`
-}
-
-// ModelDescriptor defines the general information of a model.
-type ModelDescriptor struct {
-	// CreatedAt is the date and time on which the model was built.
-	CreatedAt *time.Time `json:"createdAt,omitempty"`
-
-	// Authors contains the contact details of the people or organization responsible for the model.
-	Authors []string `json:"authors,omitempty"`
-
-	// Family is the model family, such as llama3, gpt2, qwen2, etc.
-	Family string `json:"family,omitempty"`
-
-	// Name is the model name, such as llama3-8b-instruct, gpt2-xl, etc.
-	Name string `json:"name,omitempty"`
-
-	// DocURL is the URL to get documentation on the model.
-	DocURL string `json:"docURL,omitempty"`
-
-	// SourceURL is the URL to get source code for building the model.
-	SourceURL string `json:"sourceURL,omitempty"`
-
-	// DatasetsURL contains URLs referencing datasets that the model was trained upon.
-	DatasetsURL []string `json:"datasetsURL,omitempty"`
-
-	// Version is the version of the packaged software.
-	Version string `json:"version,omitempty"`
-
-	// Revision is the source control revision identifier for the packaged software.
-	Revision string `json:"revision,omitempty"`
-
-	// Vendor is the name of the distributing entity, organization or individual.
-	Vendor string `json:"vendor,omitempty"`
-
-	// Licenses contains the license(s) under which contained software is distributed
-	// as an SPDX License Expression.
-	Licenses []string `json:"licenses,omitempty"`
-
-	// Title is the human-readable title of the model.
-	Title string `json:"title,omitempty"`
-
-	// Description is the human-readable description of the software packaged in the model.
-	Description string `json:"description,omitempty"`
-}
-
-// ModelConfig defines the execution parameters which should be used as a base
-// when running a model using an inference engine.
-type ModelConfig struct {
-	// Architecture is the model architecture, such as transformer, cnn, rnn, etc.
-	Architecture string `json:"architecture,omitempty"`
-
-	// Format is the model format, such as gguf, safetensors, onnx, etc.
-	Format string `json:"format,omitempty"`
-
-	// ParamSize is the size of the model parameters, such as "8b", "16b", "32b", etc.
-	ParamSize string `json:"paramSize,omitempty"`
-
-	// Precision is the model precision, such as bf16, fp16, int8, mixed etc.
-	Precision string `json:"precision,omitempty"`
-
-	// Quantization is the model quantization method, such as awq, gptq, etc.
-	Quantization string `json:"quantization,omitempty"`
-
-	// Capabilities defines special capabilities that the model supports.
-	Capabilities *ModelCapabilities `json:"capabilities,omitempty"`
-}
-
-// ModelCapabilities defines the special capabilities that the model supports.
-type ModelCapabilities struct {
-	// InputTypes specifies what input modalities the model can process.
-	// Values can be: "text", "image", "audio", "video", "embedding", "other".
-	InputTypes []string `json:"inputTypes,omitempty"`
-
-	// OutputTypes specifies what output modalities the model can produce.
-	// Values can be: "text", "image", "audio", "video", "embedding", "other".
-	OutputTypes []string `json:"outputTypes,omitempty"`
-
-	// KnowledgeCutoff is the date of the datasets that the model was trained on.
-	KnowledgeCutoff *time.Time `json:"knowledgeCutoff,omitempty"`
-
-	// Reasoning indicates whether the model can perform reasoning tasks.
-	Reasoning *bool `json:"reasoning,omitempty"`
-
-	// ToolUsage indicates whether the model can use external tools.
-	ToolUsage *bool `json:"toolUsage,omitempty"`
-
-	// Reward indicates whether the model is a reward model.
-	Reward *bool `json:"reward,omitempty"`
-
-	// Languages indicates the languages that the model can speak.
-	// Encoded as ISO 639 two letter codes. For example, ["en", "fr", "zh"].
-	Languages []string `json:"languages,omitempty"`
-}
-
-// ModelFS describes the layer content addresses.
-type ModelFS struct {
-	// Type is the type of the rootfs. MUST be set to "layers".
-	Type string `json:"type"`
-
-	// DiffIDs is an array of layer content hashes (DiffIDs),
-	// in order from bottom-most to top-most.
-	DiffIDs []digest.Digest `json:"diffIds"`
-}
-
 // Ensure Model implements types.ModelConfig
 var _ types.ModelConfig = (*Model)(nil)