Allow quality setting for webp images

Currently only jpeg allows a quality setting. But webp
images should also be renderable in different qualities.

This deprecates the `output_image_jpg_quality` config
and replaces it with `output_image_quality`.

app/models/alchemy/picture_variant.rb

@@ -14,6 +14,7 @@ class PictureVariant
     include Alchemy::Picture::Transformations
 
     ANIMATED_IMAGE_FORMATS = %w[gif webp]
+    ENCODABLE_IMAGE_FORMATS = %w[jpg jpeg webp]
 
     attr_reader :picture, :render_format
 
@@ -94,8 +95,8 @@ def encoded_image(image, options = {})
 
       convert_format = render_format.sub("jpeg", "jpg") != picture.image_file_format.sub("jpeg", "jpg")
 
-      if render_format =~ /jpe?g/ && (convert_format || options[:quality])
-        quality = options[:quality] || Config.get(:output_image_jpg_quality)
+      if encodable_image? && (convert_format || options[:quality])
+        quality = options[:quality] || Config.get(:output_image_quality)
         encoding_options << "-quality #{quality}"
       end
 
@@ -112,5 +113,9 @@ def encoded_image(image, options = {})
 
       image
     end
+
+    def encodable_image?
+      render_format.in?(ENCODABLE_IMAGE_FORMATS)
+    end
   end
 end

config/alchemy/config.yml

@@ -78,13 +78,13 @@ items_per_page: 15
 #
 # ==== Global Options:
 #
-#   output_image_jpg_quality  [Integer]       # If image gets rendered as JPG this is the quality setting for it. (Default 85)
+#   output_image_quality      [Integer]       # If image gets rendered as JPG or WebP this is the quality setting for it. (Default 85)
 #   preprocess_image_resize   [String]        # Use this option to resize images to the given size when they are uploaded to the image library. Downsizing example: '1000x1000>' (Default nil)
 #   image_output_format       [String]        # The global image output format setting. (Default +original+)
 #
 # NOTE: You can always override the output format in the settings of your ingredients in elements.yml, I.E. {format: 'gif'}
 #
-output_image_jpg_quality: 85
+output_image_quality: 85
 preprocess_image_resize:
 image_output_format: original
 
@@ -133,7 +133,8 @@ mailer:
   mail_from: [email protected]
   mail_to: [email protected]
   subject: A new contact form message
-  fields: [salutation, firstname, lastname, address, zip, city, phone, email, message]
+  fields:
+    [salutation, firstname, lastname, address, zip, city, phone, email, message]
   validate_fields: [lastname, email]
 
 # === User roles
@@ -166,14 +167,14 @@ uploader:
   file_size_limit: 100
   allowed_filetypes:
     alchemy/attachments:
-    - '*'
+      - "*"
     alchemy/pictures:
-    - jpg
-    - jpeg
-    - gif
-    - png
-    - svg
-    - webp
+      - jpg
+      - jpeg
+      - gif
+      - png
+      - svg
+      - webp
 
 # === Link Target Options
 #

lib/alchemy/config.rb

@@ -37,7 +37,9 @@ def deprecated_configs
 
       # A list of replaced configuration keys
       def replaced_config_keys
-        {}
+        {
+          output_image_quality: :output_image_jpg_quality
+        }
       end
 
       private

spec/models/alchemy/picture_variant_spec.rb

@@ -196,7 +196,7 @@
         it "does not flatten the image." do
           step = subject.steps[0]
           expect(step.name).to eq(:encode)
-          expect(step.arguments).to eq(["webp", ""])
+          expect(step.arguments).to eq(["webp", "-quality 85"])
         end
       end
     end
@@ -286,6 +286,90 @@
           end
         end
       end
+
+      context "and image has webp format" do
+        let(:image_file) do
+          File.new(File.expand_path("../../fixtures/image5.webp", __dir__))
+        end
+
+        let(:alchemy_picture) do
+          build_stubbed(:alchemy_picture, image_file: image_file, image_file_format: "webp")
+        end
+
+        let(:options) do
+          {format: format}
+        end
+
+        it "converts the picture into #{format}" do
+          step = subject.steps[0]
+          expect(step.name).to eq(:encode)
+          expect(step.arguments).to eq([format, "-quality 85"])
+        end
+
+        context "and quality is passed in options" do
+          let(:options) do
+            {format: format, quality: "30"}
+          end
+
+          it "sets the quality as well" do
+            step = subject.steps[0]
+            expect(step.name).to eq(:encode)
+            expect(step.arguments).to eq([format, "-quality 30"])
+          end
+        end
+      end
+    end
+  end
+
+  context "when webp format is requested" do
+    let(:options) do
+      {format: "webp"}
+    end
+
+    context "and the image file format is not WebP" do
+      it "converts image into webp and sets the default quality" do
+        step = subject.steps[0]
+        expect(step.name).to eq(:encode)
+        expect(step.arguments).to eq(["webp", "-quality 85"])
+      end
+
+      context "but quality is passed" do
+        let(:options) do
+          {format: "webp", quality: "30"}
+        end
+
+        it "converts with given quality" do
+          step = subject.steps[0]
+          expect(step.name).to eq(:encode)
+          expect(step.arguments).to eq(["webp", "-quality 30"])
+        end
+      end
+    end
+
+    context "and image already has webp format" do
+      let(:image_file) do
+        File.new(File.expand_path("../../fixtures/image5.webp", __dir__))
+      end
+
+      let(:alchemy_picture) do
+        build_stubbed(:alchemy_picture, image_file: image_file, image_file_format: "webp")
+      end
+
+      it "does not convert the picture format" do
+        expect(subject).to_not respond_to(:steps)
+      end
+
+      context "and quality is passed in options" do
+        let(:options) do
+          {format: "webp", quality: "30"}
+        end
+
+        it "converts to given quality" do
+          step = subject.steps[0]
+          expect(step.name).to eq(:encode)
+          expect(step.arguments).to eq(["webp", "-quality 30"])
+        end
+      end
     end
   end
 end