Document ActiveStorage::Preview#download

rails · Jul 20, 2021 · 460a5ae · 460a5ae
1 parent de8d345
commit 460a5ae
Showing 1 changed file with 7 additions and 0 deletions.
diff --git a/activestorage/app/models/active_storage/preview.rb b/activestorage/app/models/active_storage/preview.rb
@@ -75,6 +75,13 @@ def key
     end
   end
 
+  # Downloads the file associated with this preview's variant.
+  # Raises ActiveStorage::Preview::UnprocessedError if the preview has not been processed yet.
+  #
+  # Downloads the file associated with this variant. If no block is given, the
+  # entire file is read into memory and returned. That'll use a lot of RAM for
+  # very large files. If a block is given, then the download is streamed and
+  # yielded in chunks.
   def download(&block)
     if processed?
       variant.download(&block)