feat: Add UploadReleaseAssetFromRelease convenience helper

github/repos_releases.go

@@ -488,3 +488,59 @@ func (s *RepositoriesService) UploadReleaseAsset(ctx context.Context, owner, rep
 	}
 	return asset, resp, nil
 }
+
+// UploadReleaseAssetFromRelease uploads an asset using the UploadURL that's embedded
+// in a RepositoryRelease object.
+//
+// This is a convenience wrapper that extracts the release.UploadURL (which is usually
+// templated like "https://uploads.github.com/.../assets{?name,label}") and uploads
+// the provided file using the existing upload helpers.
+//
+// GitHub API docs: https://docs.github.com/rest/releases/assets#upload-a-release-asset
+//
+//meta:operation POST /repos/{owner}/{repo}/releases/{release_id}/assets
+func (s *RepositoriesService) UploadReleaseAssetFromRelease(ctx context.Context, release *RepositoryRelease, opts *UploadOptions, file *os.File) (*ReleaseAsset, *Response, error) {
+	if release == nil || release.UploadURL == nil {
+		return nil, nil, errors.New("release UploadURL must be provided")
+	}
+	if file == nil {
+		return nil, nil, errors.New("file must be provided")
+	}
+
+	// Extract upload URL and remove template part (e.g. "{?name,label}") if present.
+	uploadURL := *release.UploadURL
+	if idx := strings.Index(uploadURL, "{"); idx != -1 {
+		uploadURL = uploadURL[:idx]
+	}
+
+	// addOptions will append query params for name/label (same as UploadReleaseAsset)
+	u, err := addOptions(uploadURL, opts)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	stat, err := file.Stat()
+	if err != nil {
+		return nil, nil, err
+	}
+	if stat.IsDir() {
+		return nil, nil, errors.New("the asset to upload can't be a directory")
+	}
+
+	mediaType := mime.TypeByExtension(filepath.Ext(file.Name()))
+	if opts != nil && opts.MediaType != "" {
+		mediaType = opts.MediaType
+	}
+
+	req, err := s.client.NewUploadRequest(u, file, stat.Size(), mediaType)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	asset := new(ReleaseAsset)
+	resp, err := s.client.Do(ctx, req, asset)
+	if err != nil {
+		return nil, resp, err
+	}
+	return asset, resp, nil
+}