Add blacklight configuration for registering additional response form…

…ats for the #index action

Options include:

- do the default
    config.index.respond_to.yaml = true

- don't render the format
    config.index.respond_to.yaml = true

- options for render
    config.index.respond_to.yaml = { layout: 'custom-layout' }

- custom proc to render
    config.index.respond_to.yaml = lambda { render text: "stuff" }

- controller method to render
    config.index.respond_to.yaml = :my_custom_yaml_serialization

lib/blacklight/catalog.rb

@@ -27,11 +27,30 @@ def index
         format.html { }
         format.rss  { render :layout => false }
         format.atom { render :layout => false }
-
-
         format.json do
           render json: render_search_results_as_json
         end
+
+        additional_response_formats(format)
+      end
+    end
+
+    def additional_response_formats format
+      blacklight_config.index.respond_to.each do |key, config|
+        format.send key do
+          case config
+          when false
+            raise ActionController::RoutingError.new('Not Found')
+          when Hash
+            render config
+          when Proc
+            instance_exec &config
+          when Symbol, String
+            send config
+          else
+            # no-op, just render the page
+          end
+        end
       end
     end
 

lib/blacklight/configuration.rb

@@ -20,7 +20,12 @@ def default_values
           :document_solr_request_handler => nil,
           :default_document_solr_params => {},
           :show => ViewConfig::Show.new(:partials => [:show_header, :show]),
-          :index => ViewConfig::Index.new(:partials => [:index_header, :thumbnail, :index], :title_field => unique_key, :display_type_field => 'format', :group => false),
+          :index => ViewConfig::Index.new(:partials => [:index_header, :thumbnail, :index],
+            :title_field => unique_key,
+            :display_type_field => 'format',
+            :group => false,
+            :respond_to => OpenStructWithHashAccess.new()
+            ),
           :view => NestedOpenStructWithHashAccess.new(ViewConfig, 'list'),
           :spell_max => 5,
           :max_per_page => 100,

spec/controllers/catalog_controller_spec.rb

@@ -155,6 +155,49 @@ def assigns_response
       end
     end
 
+    describe "with additional formats from configuration" do
+      let(:blacklight_config) { Blacklight::Configuration.new }
+
+      before :each do
+        @controller.stub blacklight_config: blacklight_config
+        @controller.stub get_search_results: [double, double]
+      end
+
+      it "should not render when the config is false" do
+        blacklight_config.index.respond_to.yaml = false
+        expect { get :index, format: 'yaml' }.to raise_error ActionController::RoutingError
+      end
+
+      it "should render the default when the config is true" do
+        # TODO: this should really stub a template and see if it gets rendered,
+        # but how to do that is non-obvious..
+        blacklight_config.index.respond_to.yaml = true
+        expect { get :index, format: 'yaml' }.to raise_error ActionView::MissingTemplate
+      end
+
+      it "should pass a hash to the render call" do
+        blacklight_config.index.respond_to.yaml = { nothing: true, layout: false }
+        get :index, format: 'yaml'
+        expect(response.body).to be_blank
+      end
+
+      it "should evaluate a proc" do
+        blacklight_config.index.respond_to.yaml = lambda { render text: "" }
+        get :index, format: 'yaml'
+        expect(response.body).to be_empty
+      end
+
+      it "with a symbol, it should call a controller method" do
+        subject.should_receive(:render_some_yaml) do
+          subject.render nothing: true, layout: false
+        end
+
+        blacklight_config.index.respond_to.yaml = :render_some_yaml
+        get :index, format: 'yaml'
+        expect(response.body).to be_blank
+      end
+    end
+
   end # describe index action
 
   describe "update action" do

spec/lib/blacklight/configuration_spec.rb

@@ -55,6 +55,18 @@
     end
   end
 
+  describe "config.index.respond_to" do
+    it "should have a list of additional formats for index requests to respond to" do
+      @config.index.respond_to.xml = true
+
+      @config.index.respond_to.csv = { :layout => false }
+
+      @config.index.respond_to.yaml = lambda { render text: "" }
+
+      expect(@config.index.respond_to.keys).to eq [:xml, :csv, :yaml]
+    end
+  end
+
   describe "spell_max" do
     it "should default to 5" do
       expect(Blacklight::Configuration.new.spell_max).to eq 5