allow setting individual worker options in rails config, related to #111

lib/image_optim/railtie.rb

@@ -4,7 +4,13 @@ class ImageOptim
   # Adds image_optim as preprocessor for gif, jpeg, png and svg images
   class Railtie < Rails::Railtie
     config.before_configuration do |app|
-      app.config.assets.image_optim = ActiveSupport::OrderedOptions.new
+      worker_names = ImageOptim::Worker.klasses.map(&:bin_sym)
+      app.config.assets.image_optim =
+        ActiveSupport::OrderedOptions.new do |hash, key|
+          if worker_names.include?(key.to_sym)
+            hash[key] = ActiveSupport::OrderedOptions.new
+          end
+        end
     end
 
     initializer 'image_optim.initializer' do |app|

spec/image_optim/railtie_spec.rb

@@ -88,13 +88,32 @@ def self.name
         end
       end
 
-      it 'is possible to assign individual values' do
+      it 'is possible to set individual options' do
         hash = {:config_paths => 'config/image_optim.yml'}
         expect(ImageOptim).to receive(:new).with(hash)
         init_rails_app do |config|
           config.assets.image_optim.config_paths = 'config/image_optim.yml'
         end
       end
+
+      it 'is possible to set individual worker options' do
+        hash = {:advpng => {:level => 3}}
+        expect(ImageOptim).to receive(:new).with(hash)
+        init_rails_app do |config|
+          expect(config.assets.image_optim.advpng).to eq({})
+          config.assets.image_optim.advpng.level = 3
+        end
+      end
+
+      it 'is not possible to set unknown worker options' do
+        expect(ImageOptim).to receive(:new).with({})
+        init_rails_app do |config|
+          expect(config.assets.image_optim.unknown).to eq(nil)
+          expect do
+            config.assets.image_optim.unknown.level = 3
+          end.to raise_error(NoMethodError)
+        end
+      end
     end
   end