reworked the renderer

The renderer is now a bit smaller and asks the TemplateFinder for the
actual resources. That way it can just concentrate on rendering instead
of finding out, which stuff actually exists and which not.

lib/zero/renderer.rb

@@ -24,77 +24,68 @@ module Zero
     # This type map is used to extend the possible renderings for different
     # types, which the clients sends.
     #
-    # @example create a simple renderer
-    #   Renderer.new('app/templates')
+    # @example create a simple renderer with a mapping from html to text/html
+    #   Renderer.new('app/templates', {'html' => 'text/html'})
     #
     # @example create a renderer with a small map
     #   Renderer.new('app', {
     #     'html' => ['text/html', 'application/html+xml'],
     #     'json' => ['application/json', 'application/aweomse+json']
     #   })
+    # @example create a renderer with a specific layout
+    #   Renderer.new('app'. 'layouts/layout', {'html' => 'text/html'})
     #
-    # @param template_path [String] a string to templates
-    # @param type_map [Hash] a map of simple types to complex ones
-    def initialize(template_path, type_map = {})
-      @template_path = template_path
-      @type_map = type_map
+    # @param path [String] the relative path to templates
+    # @param layout [String] the key of the layouts
+    # @param types [Hash{String => Array}] a map of short type names to long ones
+    def initialize(path, layout = 'layout', types)
+      @path   = path
+      @layout = layout
+      @types  = types
     end
 
     # returns the hash of type conversions
     # @return [Hash] type conversion
-    attr_reader :type_map
+    attr_reader :types
+    # returns the key for layout files
+    # @return [String] the key for layouts
+    attr_reader :layout
     # get the path to the templates
     # @return [String] the base template path
-    attr_reader :template_path
+    attr_reader :path
     # get the tree of templates
+    #
+    # This function returns all templates with their keys.
     # @api private
     # @return [Hash] the template tree
-    attr_reader :templates
-
-    # load the template tree
-    #
-    # This method gets all templates in the `template_path` and builds an
-    # internal tree structure, where templates and types direct the request to
-    # the wanted template.
-    # @return [Self] returns the object
-    def read_template_path!
-      @templates = TemplateFinder.new(template_path, @type_map).get_templates
+    def templates
+      @templates ||= TemplateFinder.new(path, types)
     end
 
     # render a template
     #
-    # This method will render the given template, based on the type in the given
-    # context.
-    # @param name [String] the name of the template
-    # @param type [Array] a list of accept types used to find the template
-    # @param context [Object] the context in which to evaluate the template
-    # @return [String] the rendered content
-    def render(name, type, context)
-      template(name, type).render(context)
+    # This method will render the template according to the requested types.
+    # @param template [String] the template to render
+    # @param types [Array<String>] a list of types requested to render
+    # @param context [Object] any object to use for rendering
+    # @return [String] the result of rendering
+    def render(template, types, context)
+      unless templates.exist_for_types?(layout, types)
+        return load_template(template, types).render(context) 
+      end
+      load_layout_template(types).render(context) do
+        load_template(template, types).render(context)
+      end
     end
 
     private
 
-    # get the prepared template for the name and type
-    # @api private
-    # @param name [String] the name of the template
-    # @param types [Array] the types for the template
-    # @return [Tilt::Template] a prepared tilt template
-    def template(name, types)
-      if templates.has_key? name
-        types.each do |type|
-          template = templates[name][type]
-          unless template.nil?
-            # TODO Will be implemented later
-            # return template if template.kind_of?(Tilt::Template)
-            return Tilt.new(template)
-          end
-        end
-        raise ArgumentError.new(
-          "No template found for any of this types #{types.join ', '}!"
-        )
-      end
-      raise ArgumentError.new "No template found for '#{name}'!"
+    def load_template(template, types)
+      templates.get(template, types)
+    end
+
+    def load_layout_template(types)
+      templates.get(layout, types)
     end
   end
 end

spec/fixtures/templates/special_layout.html.erb

@@ -0,0 +1,3 @@
+special layout loaded
+
+<%= yield %>

spec/unit/zero/renderer/initialize_spec.rb

@@ -0,0 +1,11 @@
+require 'spec_helper'
+
+describe Zero::Renderer, '#initialize' do
+  subject { described_class.new(template_path, type_map) }
+  let(:template_path) { 'foo/' }
+  let(:type_map) { {'html' => ['text/html'] } }
+
+  its(:path)   { should be(template_path) }
+  its(:layout) { should match(/layout/) }
+  its(:types)  { should be(type_map) }
+end

spec/unit/zero/renderer/read_template_path_bang_spec.rb

@@ -1,16 +0,0 @@
-require 'spec_helper'
-
-describe Zero::Renderer, '#read_template_path!' do
-  subject { Zero::Renderer.new(template_path, type_map) }
-  let(:template_path) { 'spec/fixtures/templates/' }
-  let(:type_map)      { {'html' => ['text/html']} }
-  let(:result) { {
-    'text/html' => template_path + 'index.html.erb',
-    'json'      => template_path + 'index.json.erb'
-    } }
-
-  it "loads the templates" do
-    subject.read_template_path!
-    expect(subject.templates['index']).to eq(result)
-  end
-end

spec/unit/zero/renderer/render_spec.rb

@@ -1,7 +1,7 @@
 require 'spec_helper'
 
 describe Zero::Renderer, '#render' do
-  subject { Zero::Renderer.new(template_path, type_map) }
+  subject { described_class.new(template_path, type_map) }
   let(:template_path) { 'spec/fixtures/templates/' }
   let(:type_map) {{
     'html' => ['text/html', 'text/xml', '*/*'],
@@ -12,43 +12,54 @@ describe Zero::Renderer, '#render' do
   let(:foo_types)  { ['foo/bar', 'bar/foo'] }
   let(:binding) { SpecTemplateContext.new('foo') }
 
-  before :each do
-    subject.read_template_path!
+  context 'with default layout' do
+    it 'returns a tilt template' do
+      subject.render('index', html_types, binding).should be_kind_of(String)
+    end
+
+    it 'renders html content' do
+      subject.render('index', html_types, binding).should match('success')
+    end
+
+    it 'returns a tilt template for different types' do
+      subject.render('index', json_types, binding).should be_kind_of(String)
+    end
+
+    it 'renders json content' do
+      subject.render('index', json_types, binding).should match("{text: 'success'}")
+    end
+
+    it 'returns an ArgumentError, if given template does not exist' do
+      expect {
+        subject.render('foobar', html_types, binding)
+      }.to raise_error(ArgumentError, /Template 'foobar' does not exist/)
+    end
+
+    it 'returns an ArgumentError, if no template fits types' do
+      expect {
+        subject.render('index', foo_types, binding)
+      }.to raise_error(
+        ArgumentError, /Template 'index' not found/)
+    end
+
+    it 'uses the context' do
+      subject.render('context', html_types, binding).should match('foo')
+
+    end
   end
 
-  it 'returns a tilt template' do
-    subject.render('index', html_types, binding).should be_kind_of(String)
-  end
+  context 'with special layout' do
+    subject { described_class.new(template_path, layout, type_map) }
+    let(:layout) { 'special_layout' }
 
-  it 'renders html content' do
-    subject.render('index', html_types, binding).should match('success')
-  end
-
-  it 'returns a tilt template for different types' do
-    subject.render('index', json_types, binding).should be_kind_of(String)
-  end
-
-  it 'renders json content' do
-    subject.render('index', json_types, binding).should match("{text: 'success'}")
-  end
-
-  it 'returns an ArgumentError, if given template does not exist' do
-    expect {
-      subject.render('foobar', html_types, binding)
-    }.to raise_error(ArgumentError, "No template found for 'foobar'!")
-  end
-
-  it 'returns an ArgumentError, if no template fits types' do
-    expect {
-      subject.render('index', foo_types, binding)
-    }.to raise_error(
-      ArgumentError,
-      "No template found for any of this types #{foo_types.join ', '}!"
-    )
-  end
-
-  it 'uses the context' do
-    subject.render('context', html_types, binding).should match('foo')
+    it 'uses the layout for rendering' do
+      expect(subject.render('index', html_types, binding)
+            ).to match(/layout loaded/)
+    end
 
+    it 'renders the template into the layout' do
+      expect(subject.render('index', html_types, binding)
+            ).to match(/success/)
+    end
   end
 end

spec/unit/zero/renderer/template_path.rb

@@ -1,8 +0,0 @@
-require 'spec_helper'
-
-describe Zero::Renderer, '#template_path' do
-  subject { Zero::Renderer.new(template_path) }
-  let(:template_path) { 'foo' }
-
-  its(:type_map) { should be(template_path) }
-end

spec/unit/zero/renderer/templates_spec.rb

@@ -0,0 +1,13 @@
+require 'spec_helper'
+
+describe Zero::Renderer, '#templates' do
+  let(:object) { described_class.new(template_path, types) }
+  subject { object.templates }
+  
+  let(:template_path) { 'spec/fixtures/templates/' }
+  let(:types) { {'html' => ['text/html']} }
+
+  it 'loads the template tree' do
+    expect(subject).to be_kind_of(Zero::Renderer::TemplateFinder)
+  end
+end

spec/unit/zero/renderer/type_map_spec.rb

@@ -1,13 +0,0 @@
-require 'spec_helper'
-
-describe Zero::Renderer, '#type_map' do
-  subject { Zero::Renderer.new(template_path, type_map) }
-  let(:template_path) { 'foo' }
-  let(:type_map) { {'html' => ['text/html']} }
-
-  its(:type_map) { should be(type_map) }
-
-  it 'returns an empty Hash, if type_map is not set while initialization' do
-    Zero::Renderer.new(template_path).type_map.should eq({})
-  end
-end