Merge pull request #1 from ccocchi/extract-render-from-tempate

Extract render from tempate

lib/rabl-fast-json.rb

@@ -5,23 +5,27 @@ require 'active_support/json'
 require 'active_support/core_ext/class/attribute_accessors'
 
 require 'rabl-fast-json/version'
-require 'rabl-fast-json/helpers'
 require 'rabl-fast-json/template'
 require 'rabl-fast-json/compiler'
+
+require 'rabl-fast-json/renderer'
+
 require 'rabl-fast-json/library'
 require 'rabl-fast-json/handler'
 require 'rabl-fast-json/railtie'
 
+
+
 module RablFastJson
   extend self
-  
+
   mattr_accessor :cache_templates
   @@cache_templates = true
 
   def configure
     yield self
   end
-  
+
   def cache_templates?
     ActionController::Base.perform_caching && @@cache_templates
   end

lib/rabl-fast-json/compiler.rb

@@ -4,8 +4,6 @@ module RablFastJson
   # representing data structure
   #
   class Compiler
-    include Helpers
-
     def initialize
       @glue_count = 0
     end
@@ -49,7 +47,7 @@ module RablFastJson
     #
     def collection(data, options = {})
       object(data)
-      @template.root_name = options[:root] if root_given?(options)
+      @template.root_name = options[:root] if options[:root]
     end
 
     #
@@ -82,8 +80,8 @@ module RablFastJson
     #
     def child(name_or_data, options = {}, &block)
       data, name = extract_data_and_name(name_or_data)
-      name = options[:root] if root_given?(options)
+      name = options[:root] if options[:root]
-      if partial_given?(options)
+      if options[:partial]
         template = Library.instance.get(options[:partial])
         @template[name] = template.merge!(:_data => data)
       else

lib/rabl-fast-json/handler.rb

@@ -4,7 +4,7 @@ module RablFastJson
       cattr_accessor :default_format
       self.default_format = 'application/json'
 
-      def self.call(template)        
+      def self.call(template)
         %{
           RablFastJson::Library.instance.
             get_rendered_template(#{template.source.inspect}, self)

lib/rabl-fast-json/helpers.rb

@@ -1,11 +0,0 @@
-module RablFastJson
-  module Helpers
-    def root_given?(options) #:nodoc:
-      options[:root].present?
-    end
-
-    def partial_given?(options) #:nodoc:
-      options[:partial].present?
-    end
-  end
-end

lib/rabl-fast-json/library.rb

@@ -4,20 +4,18 @@ module RablFastJson
   class Library
     include Singleton
 
-    attr_accessor :view_renderer
-
     def initialize
       @cached_templates = {}
     end
 
     def get_rendered_template(source, context)
       path = context.instance_variable_get(:@virtual_path)
-      @view_renderer = context.instance_variable_get(:@view_renderer)
+      @lookup_context = context.lookup_context
 
       compiled_template = get_compiled_template(path, source)
-      compiled_template.context = context
+
-      body = compiled_template.render
+      format = context.params[:format] || 'json'
-      ActiveSupport::JSON.encode(compiled_template.root_name ? { compiled_template.root_name => body } : body)
+      Renderers.const_get(format.upcase!).new(context).render(compiled_template)
     end
 
     def get_compiled_template(path, source)
@@ -31,8 +29,8 @@ module RablFastJson
 
     def get(path)
       template = @cached_templates[path]
-      return template unless template.nil?
+      return template if template
-      t = @view_renderer.lookup_context.find_template(path, [], false)
+      t = @lookup_context.find_template(path, [], false)
       get_compiled_template(path, t.source)
     end
   end

lib/rabl-fast-json/renderer.rb

@@ -0,0 +1,2 @@
+require 'rabl-fast-json/renderers/base'
+require 'rabl-fast-json/renderers/json'

lib/rabl-fast-json/renderers/base.rb

@@ -0,0 +1,114 @@
+module RablFastJson
+  module Renderers
+    class PartialError < StandardError; end
+
+    class Base
+
+      def initialize(context) # :nodoc:
+        @_context = context
+        setup_render_context
+      end
+
+      #
+      # Render a template.
+      # Uses the compiled template source to get a hash with the actual
+      # data and then format the result according to the `format_result`
+      # method defined by the renderer.
+      #
+      def render(template)
+        collection_or_resource = @_context.instance_variable_get(template.data) if template.data
+        output_hash = collection_or_resource.respond_to?(:each) ? render_collection(collection_or_resource, template.source) :
+          render_resource(collection_or_resource, template.source)
+        output_hash = { template.root_name => output_hash } if template.root_name
+        format_output(output_hash)
+      end
+
+      #
+      # Format a hash into the desired output.
+      # Renderer subclasses must implement this method
+      #
+      def format_output(hash)
+        raise "Muse be implemented by renderer"
+      end
+
+      protected
+
+      #
+      # Render a single resource as a hash, according to the compiled
+      # template source passed.
+      #
+      def render_resource(data, source)
+        source.inject({}) { |output, current|
+          key, value = current
+
+          out = case value
+          when Symbol
+            data.send(value) # attributes
+          when Proc
+            instance_exec data, &value # node
+          when Array # node with condition
+            next output if !instance_exec data, &(value.first)
+            instance_exec data, &(value.last)
+          when Hash
+            current_value = value.dup
+            data_symbol = current_value.delete(:_data)
+            object = data_symbol.nil? ? data : data_symbol.to_s.start_with?('@') ? @_context.instance_variable_get(data_symbol) : data.send(data_symbol)
+
+            if key.to_s.start_with?('_') # glue
+              current_value.each_pair { |k, v|
+                output[k] = object.send(v)
+              }
+              next output
+            else # child
+              object.respond_to?(:each) ? render_collection(object, current_value) : render_resource(object, current_value)
+            end
+          end
+          output[key] = out
+          output
+        }
+      end
+
+      #
+      # Call the render_resource mtehod on each object of the collection
+      # and return an array of the returned values.
+      #
+      def render_collection(collection, source)
+        collection.map { |o| render_resource(o, source) }
+      end
+
+      #
+      # Allow to use partial inside of node blocks (they are evaluated at)
+      # rendering time.
+      #
+      def partial(template_path, options = {})
+        raise PartialError.new("No object was given to partial") unless options[:object]
+        object = options[:object]
+
+        return [] if object.respond_to?(:empty?) && object.empty?
+
+        template = Library.instance.get(template_path)
+        object.respond_to?(:each) ? render_collection(object, template.source) : render_resource(object, template.source)
+      end
+
+      #
+      # If a method is called inside a 'node' property or a 'if' lambda
+      # it will be passed to context if it exists or treated as a standard
+      # missing method.
+      #
+      def method_missing(name, *args, &block)
+        @context.respond_to?(name) ? @context.send(name, *args, &block) : super
+      end
+
+      #
+      # Copy assigns from controller's context into this
+      # renderer context to include instances variables when
+      # evaluating 'node' properties.
+      #
+      def setup_render_context
+        @_context.instance_variable_get(:@_assigns).each_pair { |k, v|
+          instance_variable_set("@#{k}", v) unless k.start_with?('_') || k == @data
+        }
+      end
+    end
+  end
+end

lib/rabl-fast-json/renderers/json.rb

@@ -0,0 +1,9 @@
+module RablFastJson
+  module Renderers
+    class JSON < Base
+      def format_output(hash)
+        ActiveSupport::JSON.encode(hash)
+      end
+    end
+  end
+end

lib/rabl-fast-json/template.rb

@@ -1,86 +1,11 @@
 module RablFastJson
   class CompiledTemplate
-    attr_accessor :source, :data, :root_name, :context
+    attr_accessor :source, :data, :root_name
 
     delegate :[], :[]=, :merge!, :to => :source
 
     def initialize
       @source = {}
     end
-    
-    def has_root_name?
-      !@root_name.nil?
-    end
-
-    def render
-      get_object_from_context
-      get_assigns_from_context
-      @object.respond_to?(:each) ? render_collection : render_resource
-    end
-  
-    def render_resource(data = nil, source = nil)
-      data ||= @object
-      source ||= @source
-      
-      source.inject({}) { |output, current|
-        key, value = current
-
-        out = case value
-        when Symbol
-          data.send(value) # attributes
-        when Proc
-          instance_exec data, &value # node
-        when Array # node with condition
-          next output if !instance_exec data, &(value.first) #value.first.call(data)
-          instance_exec data, &(value.last)
-        when Hash
-          current_value = value.dup
-          data_symbol = current_value.delete(:_data)
-          object = data_symbol.nil? ? data : data_symbol.to_s.start_with?('@') ? @context.instance_variable_get(data_symbol) : data.send(data_symbol)
-
-          if key.to_s.start_with?('_') # glue
-            current_value.each_pair { |k, v|
-              output[k] = object.send(v)
-            }
-            next output
-          else # child
-            object.respond_to?(:each) ? render_collection(object, current_value) : render_resource(object, current_value)
-          end
-        end
-        output[key] = out
-        output
-      }
-    end
-
-    def render_collection(collection = nil, source = nil)
-      collection ||= @object
-      collection.inject([]) { |output, o| output << render_resource(o, source) }
-    end
-    
-    def method_missing(name, *args, &block)
-      @context.respond_to?(name) ? @context.send(name, *args, &block) : super
-    end
-    
-    def partial(template_path, options = {})      
-      raise "No object was given to partial" if options[:object].nil?
-      object = options[:object]
-
-      return [] if object.respond_to?(:empty?) && object.empty?
-      
-      template = Library.instance.get(template_path)
-      object.respond_to?(:each) ? template.render_collection(object) : template.render_resource(object)
-    end
-    
-    protected
-    
-    def get_object_from_context
-      @object = @context.instance_variable_get(@data) if @data
-    end
-    
-    def get_assigns_from_context
-      @context.instance_variable_get(:@_assigns).each_pair { |k, v|
-        instance_variable_set("@#{k}", v) unless k.start_with?('_') || k == @data
-      }
-    end  
   end
 end

test/cache_templates_test.rb

@@ -4,31 +4,31 @@ class CacheTemplatesTest < ActiveSupport::TestCase
 
   setup do
     RablFastJson::Library.reset_instance
-    @library = RablFastJson::Library.instance 
+    @library = RablFastJson::Library.instance
-  end
-  
-  test "cache templates if perform_caching is active and cache_templates is enabled" do
     RablFastJson.cache_templates = true
-    ActionController::Base.stub(:perform_caching).and_return(true)    
+  end
+
+  test "cache templates if perform_caching is active and cache_templates is enabled" do
+    ActionController::Base.stub(:perform_caching).and_return(true)
     @library.get_compiled_template('some/path', "")
     t = @library.get_compiled_template('some/path', "attribute :id")
-    
+
     assert_equal({}, t.source)
   end
-  
+
   test "cached templates should not be modifiable in place" do
-    RablFastJson.cache_templates = true
     ActionController::Base.stub(:perform_caching).and_return(true)
-    t = @library.get_compiled_template('some/path', "")
+    @library.get_compiled_template('some/path', "")
-    assert_nil t.context
+    t = @library.get_compiled_template('some/path', "attribute :id")
-    t.context = "foobar"
+
-    assert_nil @library.get_compiled_template('some/path', "").context
+    assert_equal({}, t.source)
   end
-  
+
   test "don't cache templates cache_templates is enabled but perform_caching is not active" do
-    RablFastJson.cache_templates = true
+    ActionController::Base.stub(:perform_caching).and_return(false)
-    ActionController::Base.stub(:perform_caching).and_return(false)    
+    @library.get_compiled_template('some/path', "")
-    
+    t = @library.get_compiled_template('some/path', "attribute :id")
-    refute_equal @library.get_compiled_template('some/path', ""), @library.get_compiled_template('some/path', "")
+
+    assert_equal({ :id => :id }, t.source)
   end
 end

test/compiler_test.rb

@@ -11,6 +11,40 @@ class CompilerTest < ActiveSupport::TestCase
     assert_instance_of RablFastJson::CompiledTemplate, @compiler.compile_source("")
   end
 
+  test "object set data for the template" do
+    t = @compiler.compile_source(%{ object :@user })
+    assert_equal :@user, t.data
+    assert_equal({}, t.source)
+  end
+
+  test "object property can define root name" do
+    t = @compiler.compile_source(%{ object :@user => :author })
+    assert_equal :@user, t.data
+    assert_equal :author, t.root_name
+    assert_equal({}, t.source)
+  end
+
+  test "collection set the data for the template" do
+    t = @compiler.compile_source(%{ collection :@user })
+    assert_equal :@user, t.data
+    assert_equal({}, t.source)
+  end
+
+  test "collection property can define root name" do
+    t = @compiler.compile_source(%{ collection :@user => :users })
+    assert_equal :@user, t.data
+    assert_equal :users, t.root_name
+    assert_equal({}, t.source)
+  end
+
+  test "collection property can define root name via options" do
+    t = @compiler.compile_source(%{ collection :@user, :root => :users })
+    assert_equal :@user, t.data
+    assert_equal :users, t.root_name
+  end
+
+  # Compilation
+
   test "simple attributes are compiled to hash" do
     t = @compiler.compile_source(%{ attributes :id, :name })
     assert_equal({ :id => :id, :name => :name}, t.source)
@@ -57,11 +91,10 @@ class CompilerTest < ActiveSupport::TestCase
   end
 
   test "child with succint partial notation" do
-    @view_renderer = mock()
+    mock_template = RablFastJson::CompiledTemplate.new
-    @view_renderer.stub_chain(:lookup_context, :find_template).with('users/base', [], false).and_return(
+    mock_template.source = { :id => :id }
-      mock(:source => %{ attribute :id }))
     RablFastJson::Library.reset_instance
-    RablFastJson::Library.instance.view_renderer = @view_renderer
+    RablFastJson::Library.instance.stub(:get).with('users/base').and_return(mock_template)
 
     t = @compiler.compile_source(%{child(:user, :partial => 'users/base') })
     assert_equal( {:user => { :_data => :user, :id => :id } }, t.source)
@@ -84,38 +117,6 @@ class CompilerTest < ActiveSupport::TestCase
     }, t.source)
   end
 
-  test "object set data for the template" do
-    t = @compiler.compile_source(%{ object :@user })
-    assert_equal :@user, t.data
-    assert_equal({}, t.source)
-  end
-
-  test "object property can define root name" do
-    t = @compiler.compile_source(%{ object :@user => :author })
-    assert_equal :@user, t.data
-    assert_equal :author, t.root_name
-    assert_equal({}, t.source)
-  end
-
-  test "collection set the data for the template" do
-    t = @compiler.compile_source(%{ collection :@user })
-    assert_equal :@user, t.data
-    assert_equal({}, t.source)
-  end
-
-  test "collection property can define root name" do
-    t = @compiler.compile_source(%{ collection :@user => :users })
-    assert_equal :@user, t.data
-    assert_equal :users, t.root_name
-    assert_equal({}, t.source)
-  end
-
-  test "collection property can define root name via options" do
-    t = @compiler.compile_source(%{ collection :@user, :root => :users })
-    assert_equal :@user, t.data
-    assert_equal :users, t.root_name
-  end
-
   test "extends use other template source as itself" do
     template = mock('template', :source => { :id => :id })
     RablFastJson::Library.reset_instance

test/deep_nesting_test.rb

@@ -21,15 +21,11 @@ class DeepNestingTest < ActiveSupport::TestCase
     @user.stub(:posts).and_return([@post])
     @user.stub(:respond_to?).with(:each).and_return(false)
 
-    @view_renderer = mock()
-    @view_renderer.stub_chain(:lookup_context, :find_template).with('comments/show', [], false).and_return(
-      mock(:source => %{ object :@comment\n attribute :content }))
-
     @context = Context.new
     @context.stub(:instance_variable_get).with(:@user).and_return(@user)
-    @context.stub(:instance_variable_get).with(:@view_renderer).and_return(@view_renderer)
     @context.stub(:instance_variable_get).with(:@virtual_path).and_return('users/show')
     @context.stub(:instance_variable_get).with(:@_assigns).and_return({})
+    @context.stub(:lookup_context).and_return(mock(:find_template => mock(:source => %{ object :@comment\n attribute :content })))
   end
 
   test "compile and render deep nesting template" do

test/non_restful_response_test.rb

@@ -3,18 +3,18 @@ require 'test_helper'
 class NonRestfulResponseTest < ActiveSupport::TestCase
   setup do
     RablFastJson::Library.reset_instance
-    
+
     @user = User.new(1, 'foo', 'male')
     @user.stub_chain(:posts, :count).and_return(10)
     @user.stub(:respond_to?).with(:each).and_return(false)
-    
+
     @context = Context.new
     @context.stub(:instance_variable_get).with(:@user).and_return(@user)
-    @context.stub(:instance_variable_get).with(:@view_renderer).and_return(mock())
     @context.stub(:instance_variable_get).with(:@virtual_path).and_return('user/show')
     @context.stub(:instance_variable_get).with(:@_assigns).and_return({'user' => @user})
+    @context.stub(:lookup_context)
   end
-  
+
   test "compile and render non restful resource" do
     source = %{
       object false
@@ -23,13 +23,13 @@ class NonRestfulResponseTest < ActiveSupport::TestCase
         attributes :id, :name
       end
     }
-    
+
     assert_equal(ActiveSupport::JSON.encode({
       :post_count => 10,
       :user => {
         :id => 1,
         :name => 'foo'
       }
-    }), RablFastJson::Library.instance.get_rendered_template(source, @context))    
+    }), RablFastJson::Library.instance.get_rendered_template(source, @context))
   end
 end

test/renderers/json_renderer_test.rb

@@ -1,72 +1,80 @@
 require 'test_helper'
 
-class TestCompiledTemplate < ActiveSupport::TestCase
+class TestJsonRenderer < ActiveSupport::TestCase
 
   setup do
-    @context = Context.new
     @data = User.new(1, 'foobar', 'male')
     @data.stub(:respond_to?).with(:each).and_return(false)
+
+    @context = Context.new
     @context.stub(:instance_variable_get).with(:@data).and_return(@data)
     @context.stub(:instance_variable_get).with(:@_assigns).and_return({})
+
     @template = RablFastJson::CompiledTemplate.new
-    @template.context = @context
     @template.data = :@data
   end
 
+  def render_json_output
+    RablFastJson::Renderers::JSON.new(@context).render(@template).to_s
+  end
+
   test "render object wth empty template" do
     @template.source = {}
-    assert_equal({}, @template.render)
+    assert_equal %q({}), render_json_output
   end
 
   test "render collection with empty template" do
     @context.stub(:instance_variable_get).with(:@data).and_return([@data])
     @template.source = {}
-    assert_equal([{}], @template.render)
+    assert_equal %q([{}]), render_json_output
   end
 
   test "render single object attributes" do
     @template.source = { :id => :id, :name => :name }
-    assert_equal({ :id => 1, :name => 'foobar'}, @template.render)
+    assert_equal %q({"id":1,"name":"foobar"}), render_json_output
   end
 
-  test "render object as a child" do
+  test "render child with object association" do
+    @data.stub(:address).and_return(mock(:city => 'Paris'))
+    @template.source = { :address => { :_data => :address, :city => :city } }
+    assert_equal %q({"address":{"city":"Paris"}}), render_json_output
+  end
+
+  test "render child with arbitrary data source" do
     @template.source = { :author => { :_data => :@data, :name => :name } }
-    assert_equal({ :author => { :name => 'foobar' } }, @template.render)
+    assert_equal %q({"author":{"name":"foobar"}}), render_json_output
   end
 
   test "render glued attributes from single object" do
     @template.source = { :_glue0 => { :_data => :@data, :name => :name } }
-    assert_equal({ :name => 'foobar' }, @template.render)
+    assert_equal %q({"name":"foobar"}), render_json_output
   end
 
   test "render collection with attributes" do
     @data = [User.new(1, 'foo', 'male'), User.new(2, 'bar', 'female')]
     @context.stub(:instance_variable_get).with(:@data).and_return(@data)
     @template.source = { :uid => :id, :name => :name, :gender => :sex }
-    assert_equal([
+    assert_equal %q([{"uid":1,"name":"foo","gender":"male"},{"uid":2,"name":"bar","gender":"female"}]), render_json_output
-      { :uid => 1, :name => 'foo', :gender => 'male'},
-      { :uid => 2, :name => 'bar', :gender => 'female'}
-    ], @template.render)
   end
 
   test "render node property" do
-    proc = lambda { |object| object.sex }
+    proc = lambda { |object| object.name }
-    @template.source = { :sex => proc }
+    @template.source = { :name => proc }
-    assert_equal({ :sex => 'male' }, @template.render)
+    assert_equal %q({"name":"foobar"}), render_json_output
   end
 
   test "render node property with true condition" do
     condition = lambda { |u| true }
     proc = lambda { |object| object.name }
     @template.source = { :name => [condition, proc] }
-    assert_equal({ :name => 'foobar' }, @template.render)
+    assert_equal %q({"name":"foobar"}), render_json_output
   end
 
   test "render node property with false condition" do
     condition = lambda { |u| false }
     proc = lambda { |object| object.name }
     @template.source = { :name => [condition, proc] }
-    assert_equal({}, @template.render)
+    assert_equal %q({}), render_json_output
   end
 
   test "partial should be evaluated at rendering time" do
@@ -76,27 +84,27 @@ class TestCompiledTemplate < ActiveSupport::TestCase
 
     # Stub Library#get
     t = RablFastJson::CompiledTemplate.new
-    t.source, t.context = { :name => :name }, @context
+    t.source = { :name => :name }
     RablFastJson::Library.reset_instance
     RablFastJson::Library.instance.should_receive(:get).with('users/base').and_return(t)
 
     @template.data = false
     @template.source = { :user => ->(s) { partial('users/base', :object => @user) } }
 
-    assert_equal({ :user => { :name => 'foobar' } }, @template.render)
+    assert_equal %q({"user":{"name":"foobar"}}), render_json_output
   end
 
-  test "partial with nil values should raise an error" do
+  test "partial with no values should raise an error" do
     @template.data = false
     @template.source = { :user => ->(s) { partial('users/base') } }
 
-    assert_raises(RuntimeError) { @template.render }
+    assert_raises(RablFastJson::Renderers::PartialError) { render_json_output }
   end
 
   test "partial with empty values should not raise an error" do
     @template.data = false
     @template.source = { :users => ->(s) { partial('users/base', :object => []) } }
 
-    assert_equal({ :users => [] }, @template.render)
+    assert_equal %q({"users":[]}), render_json_output
   end
 end

test/test_helper.rb

@@ -35,16 +35,11 @@ class Context
 
   def initialize
     @_assigns = {}
-    @virtual_path = '/users'
   end
 
-  def set_assign(key, value)
+  def params
-    @_assigns[key] = value
+    {}
-  end
-
-  def get_assign(key)
-    @_assigns[key]
   end
 end
-  
+
 User = Struct.new(:id, :name, :sex)