create empty config entry

Signed-off-by: Jaideep Rao <[email protected]>

olot/oci/oci_common.py

@@ -27,6 +27,7 @@ class MediaTypes:
         layer: MediaType = "application/vnd.oci.image.layer.v1.tar"
         layer_gzip: MediaType = "application/vnd.oci.image.layer.v1.tar+gzip"
         empty: MediaType = "application/vnd.oci.empty.v1+json"
+        config: MediaType = "application/vnd.oci.image.config.v1+json"
 
 Digest = Annotated[str, Field(
         ...,

olot/oci/oci_image_manifest.py

@@ -4,14 +4,14 @@
 
 from __future__ import annotations
 
-from typing import Annotated, List, Optional
+from typing import Annotated, List, Optional, Dict
 import os
 import subprocess
 from pathlib import Path
 
 from pydantic import BaseModel, Field
 
-from olot.oci.oci_common import Digest, Urls, Keys, Values, MediaTypes, MediaType
+from olot.oci.oci_common import Urls, Keys, Values, MediaTypes, MediaType
 from olot.utils.types import Int64, Base64, Annotations
 from olot.utils.files import MIMETypes
 
@@ -96,24 +96,27 @@
 
 class ContentDescriptor(BaseModel):
     mediaType: MediaType = Field(
-        ..., description='the mediatype of the referenced object'
+        ..., description="The media type of the referenced object"
     )
-    size: Int64 = Field(..., description='the size in bytes of the referenced object')
-    digest: Digest = Field(
-        ...,
-        description="the cryptographic checksum digest of the object, in the pattern '<algorithm>:<encoded>'",
+    size: Int64 = Field(
+        ..., description="The size in bytes of the referenced object"
+    )
+    digest: str = Field(
+        ..., description="The cryptographic checksum digest of the object, in the pattern '<algorithm>:<encoded>'"
     )
     urls: Optional[Urls] = Field(
-        None, description='a list of urls from which this object may be downloaded'
+        None, description="A list of URLs from which this object may be downloaded"
     )
     data: Optional[Base64] = Field(
-        None, description='an embedding of the targeted content (base64 encoded)'
+        None, description="An embedding of the targeted content (base64 encoded)"
     )
     artifactType: Optional[MediaType] = Field(
-        None, description='the IANA media type of this artifact'
+        None, description="The IANA media type of this artifact"
     )
-    annotations: Optional[Annotations] = None
+    annotations: Optional[Dict[str, str]] = None
 
+    class Config:
+        exclude_none = True
 
 class OCIImageManifest(BaseModel):
     schemaVersion: Annotated[int, Field(ge=2, le=2)] = Field(
@@ -193,12 +196,12 @@ def create_manifest_layers(files: List[Path], blob_layers: dict) -> List[Content
             mediaType=get_file_media_type(file),
             size=os.stat(file).st_size,
             digest=f"sha256:{file_digest}",
-            urls=None,
-            data=None,
-            artifactType=None,
             annotations= {
                 Keys.image_title_annotation: os.path.basename(file)
-            }
+            },
+            urls = None,
+            data = None,
+            artifactType = None,
         )
         layers.append(layer)
     return layers

olot/oci_artifact.py

@@ -1,13 +1,12 @@
 from pathlib import Path
 import os
-import datetime
 import json
 import argparse
 from typing import List
 
 from olot.oci.oci_image_manifest import create_oci_image_manifest, create_manifest_layers
 from olot.oci.oci_image_layout import create_ocilayout
-from olot.oci.oci_common import Keys, MediaTypes
+from olot.oci.oci_common import MediaTypes, Values
 from olot.oci.oci_image_index import Manifest, create_oci_image_index
 from olot.utils.files import MIMETypes, tarball_from_file, targz_from_file
 from olot.utils.types import compute_hash_of_str
@@ -39,16 +38,12 @@ def create_oci_artifact_from_model(source_dir: Path, dest_dir: Path):
 
     # Create the OCI image manifest
     manifest_layers = create_manifest_layers(model_files, layers)
-    annotations = {
-        Keys.image_created_annotation: datetime.datetime.now().isoformat()
-    }
     artifactType = MIMETypes.mlmodel
     manifest = create_oci_image_manifest(
         artifactType=artifactType,
         layers=manifest_layers,
-        annotations=annotations
     )
-    manifest_json = json.dumps(manifest.model_dump(), indent=4, sort_keys=True)
+    manifest_json = json.dumps(manifest.dict(exclude_none=True), indent=4, sort_keys=True)
     manifest_SHA = compute_hash_of_str(manifest_json)
     with open(sha256_path / manifest_SHA, "w") as f:
         f.write(manifest_json)
@@ -60,22 +55,27 @@ def create_oci_artifact_from_model(source_dir: Path, dest_dir: Path):
                 mediaType=MediaTypes.manifest,
                 size=os.stat(sha256_path / manifest_SHA).st_size,
                 digest=f"sha256:{manifest_SHA}",
-                urls=None,
-                platform=None,
-                annotations=None
+                urls = None,
             )
         ]
     )
-    index_json = json.dumps(index.model_dump(), indent=4, sort_keys=True)
+    index_json = json.dumps(index.dict(exclude_none=True), indent=4, sort_keys=True)
     with open(dest_dir / "index.json", "w") as f:
         f.write(index_json)
 
-
     # Create the OCI-layout file
     oci_layout = create_ocilayout()
     with open(dest_dir / "oci-layout", "w") as f:
         f.write(json.dumps(oci_layout.model_dump(), indent=4, sort_keys=True))
 
+    # Create empty config file with digest as name
+    empty_config: dict[str, str] = {}
+    empty_digest_split = Values.empty_digest.split(":")
+    if len(empty_digest_split) == 2:
+        with open(dest_dir / "blobs" / "sha256" / empty_digest_split[1], "w") as f:
+            f.write(json.dumps(empty_config))
+    else:
+        raise ValueError(f"Invalid empty_digest format: {Values.empty_digest}")
 
 def create_blobs(model_files: List[Path], dest_dir: Path):
     """

tests/data/sample-model/oci/blobs/sha256/44136fa355b3678a1146ad16f7e8649e94fb4fc21fe77e8310c060f61caaff8a

@@ -0,0 +1 @@
+{}

tests/data/sample-model/oci/blobs/sha256/70202a75d040e8a232a904310700749d8e630a68e4c91f42173ec597e137c470

@@ -0,0 +1,37 @@
+{
+    "artifactType": "application/x-mlmodel",
+    "config": {
+        "data": "e30=",
+        "digest": "sha256:44136fa355b3678a1146ad16f7e8649e94fb4fc21fe77e8310c060f61caaff8a",
+        "mediaType": "application/vnd.oci.empty.v1+json",
+        "size": 2
+    },
+    "layers": [
+        {
+            "annotations": {
+                "org.opencontainers.image.title": "model.joblib"
+            },
+            "digest": "sha256:80da85cc1eb84676a6adbc8b495381463f1f2302425a96033dc51a81e17cb0bb",
+            "mediaType": "application/octet-stream",
+            "size": 3299
+        },
+        {
+            "annotations": {
+                "org.opencontainers.image.title": "README.md"
+            },
+            "digest": "sha256:69c637f302502a950e7a5072f78032ce593d73797845751debed90558638d5a1",
+            "mediaType": "text/plain",
+            "size": 6625
+        },
+        {
+            "annotations": {
+                "org.opencontainers.image.title": "hello.md"
+            },
+            "digest": "sha256:06cd6f2c31be8e4d5a1cea6d6c1e7401cc0128c21439456eaf964180b00dfda1",
+            "mediaType": "text/plain",
+            "size": 72
+        }
+    ],
+    "mediaType": "application/vnd.oci.image.manifest.v1+json",
+    "schemaVersion": 2
+}

tests/data/sample-model/oci/index.json

@@ -0,0 +1,11 @@
+{
+    "manifests": [
+        {
+            "digest": "sha256:70202a75d040e8a232a904310700749d8e630a68e4c91f42173ec597e137c470",
+            "mediaType": "application/vnd.oci.image.manifest.v1+json",
+            "size": 1250
+        }
+    ],
+    "mediaType": "application/vnd.oci.image.index.v1+json",
+    "schemaVersion": 2
+}

tests/data/sample-model/oci/oci-layout

@@ -0,0 +1,3 @@
+{
+    "imageLayoutVersion": "1.0.0"
+}