3 files changed, 25 insertions, 5 deletions
diff --git a/tools/nixery/storage/filesystem.go b/tools/nixery/storage/filesystem.go
index 926e9257a1..bd757587b4 100644
--- a/tools/nixery/storage/filesystem.go
+++ b/tools/nixery/storage/filesystem.go
@@ -49,7 +49,8 @@ func (b *FSBackend) Name() string {
 	return fmt.Sprintf("Filesystem (%s)", b.path)
 }
 
-func (b *FSBackend) Persist(ctx context.Context, key string, f Persister) (string, int64, error) {
+// TODO(tazjin): Implement support for persisting content-types for the filesystem backend.
+func (b *FSBackend) Persist(ctx context.Context, key, _type string, f Persister) (string, int64, error) {
 	full := path.Join(b.path, key)
 	dir := path.Dir(full)
 	err := os.MkdirAll(dir, 0755)
diff --git a/tools/nixery/storage/gcs.go b/tools/nixery/storage/gcs.go
index 61b5dea523..eac34461af 100644
--- a/tools/nixery/storage/gcs.go
+++ b/tools/nixery/storage/gcs.go
@@ -80,17 +80,36 @@ func (b *GCSBackend) Name() string {
 	return "Google Cloud Storage (" + b.bucket + ")"
 }
 
-func (b *GCSBackend) Persist(ctx context.Context, path string, f Persister) (string, int64, error) {
+func (b *GCSBackend) Persist(ctx context.Context, path, contentType string, f Persister) (string, int64, error) {
 	obj := b.handle.Object(path)
 	w := obj.NewWriter(ctx)
 
 	hash, size, err := f(w)
 	if err != nil {
-		log.WithError(err).WithField("path", path).Error("failed to upload to GCS")
+		log.WithError(err).WithField("path", path).Error("failed to write to GCS")
 		return hash, size, err
 	}
 
-	return hash, size, w.Close()
+	err = w.Close()
+	if err != nil {
+		log.WithError(err).WithField("path", path).Error("failed to complete GCS upload")
+		return hash, size, err
+	}
+
+	// GCS natively supports content types for objects, which will be
+	// used when serving them back.
+	if contentType != "" {
+		_, err = obj.Update(ctx, storage.ObjectAttrsToUpdate{
+			ContentType: contentType,
+		})
+
+		if err != nil {
+			log.WithError(err).WithField("path", path).Error("failed to update object attrs")
+			return hash, size, err
+		}
+	}
+
+	return hash, size, nil
 }
 
 func (b *GCSBackend) Fetch(ctx context.Context, path string) (io.ReadCloser, error) {
diff --git a/tools/nixery/storage/storage.go b/tools/nixery/storage/storage.go
index 4040ef08dc..fd496f440a 100644
--- a/tools/nixery/storage/storage.go
+++ b/tools/nixery/storage/storage.go
@@ -36,7 +36,7 @@ type Backend interface {
 	// It needs to return the SHA256 hash of the data written as
 	// well as the total number of bytes, as those are required
 	// for the image manifest.
-	Persist(context.Context, string, Persister) (string, int64, error)
+	Persist(ctx context.Context, path, contentType string, f Persister) (string, int64, error)
 
 	// Fetch retrieves data from the storage backend.
 	Fetch(ctx context.Context, path string) (io.ReadCloser, error)