posts: move expunged image to trash folder.

When a post is expunged, move the image to a trash folder so it can be
recovered if needed.

app/logical/storage_manager.rb

@@ -50,6 +50,24 @@ class StorageManager
     raise NotImplementedError, "open not implemented"
   end
 
+  # Copy the file from src_path to dest_path.
+  #
+  # @param src_path [String] The file to copy.
+  # @param dest_path [String] The location to copy the file to.
+  def copy(src_path, dest_path)
+    file = open(src_path)
+    store(file, dest_path)
+  end
+
+  # Move the file from src_path to dest_path.
+  #
+  # @param src_path [String] The file to move.
+  # @param dest_path [String] The location to move the file to.
+  def move(src_path, dest_path)
+    copy(src_path, dest_path)
+    delete(src_path)
+  end
+
   # Return the full URL of the file at the given path, or nil if the file
   # doesn't have an URL.
   # @return [String, nil] the file URL

app/models/media_asset.rb

@@ -24,8 +24,7 @@ class MediaAsset < ApplicationRecord
 
   # Processing: The asset's files are currently being resized and distributed to the backend servers.
   # Active: The asset has been successfully uploaded and is ready to use.
-  # Deleted: The asset's files have been deleted by moving them to a trash folder. They can be undeleted
-  #          by moving them out of the trash folder. (Not implemented yet).
+  # Deleted: The asset's files have been deleted by moving them to a trash folder. They can be undeleted by moving them out of the trash folder.
   # Expunged: The asset's files have been permanently deleted.
   # Failed: The asset failed to upload. The asset may be in a partially uploaded state, with some
   #         files missing or incompletely transferred.
@@ -62,6 +61,11 @@ class MediaAsset < ApplicationRecord
       backup_storage_service.store(file, file_path)
     end
 
+    def trash_file!
+      storage_service.move(file_path, "/trash/#{file_path}")
+      backup_storage_service.move(file_path, "/trash/#{file_path}")
+    end
+
     def delete_file!
       storage_service.delete(file_path)
       backup_storage_service.delete(file_path)
@@ -276,6 +280,14 @@ class MediaAsset < ApplicationRecord
       raise
     end
 
+    def trash!
+      variants.each(&:trash_file!)
+      update!(status: :deleted)
+    rescue
+      update!(status: :failed)
+      raise
+    end
+
     def delete_files!
       variants.each(&:delete_file!)
     end

app/models/post.rb

@@ -756,7 +756,7 @@ class Post < ApplicationRecord
           decrement_tag_post_counts
           remove_from_all_pools
           remove_from_fav_groups
-          media_asset.expunge!
+          media_asset.trash!
           destroy
           update_parent_on_destroy
         end