provider: add argument to pass a subject

Signed-off-by: Tiziano Müller <[email protected]>

Author: dev-zero

oras/provider.py

@@ -5,6 +5,7 @@
 import copy
 import os
 import urllib
+from dataclasses import asdict, dataclass
 from http.cookiejar import DefaultCookiePolicy
 from typing import Callable, List, Optional, Tuple, Union
 
@@ -23,6 +24,13 @@
 container_type = Union[str, oras.container.Container]
 
 
+@dataclass
+class Subject:
+    mediaType: str
+    digest: str
+    size: int
+
+
 class Registry:
     """
     Direct interactions with an OCI registry.
@@ -626,6 +634,8 @@ def push(self, *args, **kwargs) -> requests.Response:
         :type manifest_annotations: dict
         :param target: target location to push to
         :type target: str
+        :param subject: optional subject reference
+        :type subject: Subject
         """
         container = self.get_container(kwargs["target"])
         self.load_configs(container, configs=kwargs.get("config_path"))
@@ -700,6 +710,10 @@ def push(self, *args, **kwargs) -> requests.Response:
         if manifest_annots:
             manifest["annotations"] = manifest_annots
 
+        subject = kwargs.get("subject")
+        if subject:
+            manifest["subject"] = asdict(subject)
+
         # Prepare the manifest config (temporary or one provided)
         manifest_config = kwargs.get("manifest_config")
         config_annots = annotset.get_annotations("$config")