1 files changed, 38 insertions, 0 deletions
diff --git a/activestorage/lib/active_storage/transformers/mini_magick_transformer.rb b/activestorage/lib/active_storage/transformers/mini_magick_transformer.rb
new file mode 100644
index 0000000000..e8e99cea9e
--- /dev/null
+++ b/activestorage/lib/active_storage/transformers/mini_magick_transformer.rb
@@ -0,0 +1,38 @@
+# frozen_string_literal: true
+
+require "mini_magick"
+
+module ActiveStorage
+  module Transformers
+    class MiniMagickTransformer < Transformer
+      private
+        def process(file, format:)
+          image = MiniMagick::Image.new(file.path, file)
+
+          transformations.each do |name, argument_or_subtransformations|
+            image.mogrify do |command|
+              if name.to_s == "combine_options"
+                argument_or_subtransformations.each do |subtransformation_name, subtransformation_argument|
+                  pass_transform_argument(command, subtransformation_name, subtransformation_argument)
+                end
+              else
+                pass_transform_argument(command, name, argument_or_subtransformations)
+              end
+            end
+          end
+
+          image.format(format) if format
+
+          image.tempfile.tap(&:open)
+        end
+
+        def pass_transform_argument(command, method, argument)
+          if argument == true
+            command.public_send(method)
+          elsif argument.present?
+            command.public_send(method, argument)
+          end
+        end
+    end
+  end
+end