Support for platform fields and ensure all manifests are resolved when getting index (#182)

Author: jonesbusy

src/main/java/land/oras/Index.java

@@ -34,9 +34,20 @@ public class Index {
     private final String artifactType;
     private final List<ManifestDescriptor> manifests;
 
-    private Index(int schemaVersion, String mediaType, String artifactType, List<ManifestDescriptor> manifests) {
+    /**
+     * The manifest descriptor
+     */
+    private final transient ManifestDescriptor descriptor;
+
+    private Index(
+            int schemaVersion,
+            String mediaType,
+            String artifactType,
+            List<ManifestDescriptor> manifests,
+            ManifestDescriptor descriptor) {
         this.schemaVersion = schemaVersion;
         this.mediaType = mediaType;
+        this.descriptor = descriptor;
         this.artifactType = artifactType;
         this.manifests = manifests;
     }
@@ -73,6 +84,23 @@ public List<ManifestDescriptor> getManifests() {
         return manifests;
     }
 
+    /**
+     * Get the descriptor
+     * @return The descriptor
+     */
+    public ManifestDescriptor getDescriptor() {
+        return descriptor;
+    }
+
+    /**
+     * Return a new index with the given descriptor
+     * @param descriptor The descriptor
+     * @return The manifest
+     */
+    public Index withDescriptor(ManifestDescriptor descriptor) {
+        return new Index(schemaVersion, mediaType, artifactType, manifests, descriptor);
+    }
+
     /**
      * Return the JSON representation of the index
      * @return The JSON string
@@ -96,6 +124,6 @@ public static Index fromJson(String json) {
      * @return The index
      */
     public static Index fromManifests(List<ManifestDescriptor> descriptors) {
-        return new Index(2, Const.DEFAULT_INDEX_MEDIA_TYPE, null, descriptors);
+        return new Index(2, Const.DEFAULT_INDEX_MEDIA_TYPE, null, descriptors, null);
     }
 }

src/main/java/land/oras/ManifestDescriptor.java

@@ -20,6 +20,7 @@
 
 package land.oras;
 
+import java.util.Map;
 import land.oras.utils.JsonUtils;
 import org.jspecify.annotations.NullMarked;
 import org.jspecify.annotations.Nullable;
@@ -35,18 +36,32 @@ public final class ManifestDescriptor {
     private final String digest;
     private final long size;
 
+    @Nullable
+    private final Map<String, String> platform;
+
+    @Nullable
+    private final Map<String, String> annotations;
+
     /**
      * Constructor
      * @param artifactType The optional artifact type
      * @param mediaType The media type
      * @param digest The digest
      * @param size The size
      */
-    private ManifestDescriptor(@Nullable String artifactType, String mediaType, String digest, long size) {
+    private ManifestDescriptor(
+            @Nullable String artifactType,
+            String mediaType,
+            String digest,
+            long size,
+            @Nullable Map<String, String> platform,
+            @Nullable Map<String, String> annotations) {
         this.artifactType = artifactType;
         this.mediaType = mediaType;
         this.digest = digest;
         this.size = size;
+        this.platform = platform;
+        this.annotations = annotations;
     }
 
     /**
@@ -81,6 +96,22 @@ public long getSize() {
         return size;
     }
 
+    /**
+     * Get the platform
+     * @return The platform
+     */
+    public Map<String, String> getPlatform() {
+        return platform;
+    }
+
+    /**
+     * Get the annotations
+     * @return The annotations
+     */
+    public Map<String, String> getAnnotations() {
+        return annotations;
+    }
+
     /**
      * Return the JSON representation of the manifest
      * @return The JSON string
@@ -89,6 +120,15 @@ public String toJson() {
         return JsonUtils.toJson(this);
     }
 
+    /**
+     * Create a manifest descriptor from a JSON string
+     * @param json The JSON string
+     * @return The manifest
+     */
+    public static ManifestDescriptor fromJson(String json) {
+        return JsonUtils.fromJson(json, ManifestDescriptor.class);
+    }
+
     /**
      * Return this manifest descriptor as a subject
      * @return The subject
@@ -105,6 +145,6 @@ public Subject toSubject() {
      * @return The subject
      */
     public static ManifestDescriptor of(String mediaType, String digest, long size) {
-        return new ManifestDescriptor(null, mediaType, digest, size);
+        return new ManifestDescriptor(null, mediaType, digest, size, null, null);
     }
 }