Merge pull request #32471 from janko-m/use-image_processing-gem

Use ImageProcessing gem for ActiveStorage variants

2 files changed, 18 insertions, 7 deletions

diff --git a/guides/source/active_storage_overview.md b/guides/source/active_storage_overview.md
index d67f65e88a..4a915b1083 100644
--- a/guides/source/active_storage_overview.md
+++ b/guides/source/active_storage_overview.md
@@ -337,14 +337,15 @@ rails_blob_path(user.avatar, disposition: "attachment")
 Transforming Images
 -------------------
 
-To create variation of the image, call `variant` on the Blob.
-You can pass any [MiniMagick](https://github.com/minimagick/minimagick)
-supported transformation to the method.
+To create variation of the image, call `variant` on the Blob. You can pass
+any transformation to the method supported by the processor. The default
+processor is [MiniMagick](https://github.com/minimagick/minimagick), but you
+can also use [Vips](http://www.rubydoc.info/gems/ruby-vips/Vips/Image).
 
-To enable variants, add `mini_magick` to your `Gemfile`:
+To enable variants, add the `image_processing` gem to your `Gemfile`:
 
 ```ruby
-gem 'mini_magick'
+gem 'image_processing', '~> 1.2'
 ```
 
 When the browser hits the variant URL, Active Storage will lazy transform the
@@ -352,7 +353,15 @@ original blob into the format you specified and redirect to its new service
 location.
 
 ```erb
-<%= image_tag user.avatar.variant(resize: "100x100") %>
+<%= image_tag user.avatar.variant(resize_to_fit: [100, 100]) %>
+```
+
+To switch to the Vips processor, you would add the following to
+`config/application.rb`:
+
+```ruby
+# Use Vips for processing variants.
+config.active_storage.variant_processor = :vips
 ```
 
 Previewing Files
@@ -366,7 +375,7 @@ the box, Active Storage supports previewing videos and PDF documents.
 <ul>
   <% @message.files.each do |file| %>
     <li>
-      <%= image_tag file.preview(resize: "100x100>") %>
+      <%= image_tag file.preview(resize_to_limit: [100, 100]) %>
     </li>
   <% end %>
 </ul>
diff --git a/guides/source/configuring.md b/guides/source/configuring.md
index 7d5ca4b8a7..c98e9b719c 100644
--- a/guides/source/configuring.md
+++ b/guides/source/configuring.md
@@ -778,6 +778,8 @@ normal Rails server.
 
 `config.active_storage` provides the following configuration options:
 
+* `config.active_storage.variant_processor` accepts a symbol `:mini_magick` or `:vips`, specifying whether variant transformations will be performed with MiniMagick or ruby-vips. The default is `:mini_magick`.
+
 * `config.active_storage.analyzers` accepts an array of classes indicating the analyzers available for Active Storage blobs. The default is `[ActiveStorage::Analyzer::ImageAnalyzer, ActiveStorage::Analyzer::VideoAnalyzer]`. The former can extract width and height of an image blob; the latter can extract width, height, duration, angle, and aspect ratio of a video blob.
 
 * `config.active_storage.previewers` accepts an array of classes indicating the image previewers available in Active Storage blobs. The default is `[ActiveStorage::Previewer::PDFPreviewer, ActiveStorage::Previewer::VideoPreviewer]`. The former can generate a thumbnail from the first page of a PDF blob; the latter from the relevant frame of a video blob.