storageImageSource: add Size()

Teach storageImageSource ImageSource objects to return their size, too. A consumer that can do the type assertion can avoid some parsing that we do when wrapping an ImageSource to create an Image if it was previously only initializing the Image to get this one piece of information. Signed-off-by: Nalin Dahyabhai <[email protected]>
containers · Dec 11, 2017 · d4b0a1c · d4b0a1c
1 parent b937756
commit d4b0a1c
Showing 1 changed file with 6 additions and 0 deletions.
diff --git a/storage/storage_image.go b/storage/storage_image.go
@@ -776,6 +776,12 @@ func (s *storageImageSource) getSize() (int64, error) {
 	return sum, nil
 }
 
+// Size() adds up the sizes of the image's data blobs (which includes the configuration blob), the
+// signatures, and the uncompressed sizes of all of the image's layers.
+func (s *storageImageSource) Size() (int64, error) {
+	return s.getSize()
+}
+
 // Size() returns the previously-computed size of the image, with no error.
 func (s *storageImageCloser) Size() (int64, error) {
 	return s.size, nil