First implementation of fragment cache

lib/rabl-rails.rb

@@ -6,6 +6,7 @@ require 'active_support/core_ext/class/attribute_accessors'
 
 require 'rabl-rails/version'
 require 'rabl-rails/template'
+require 'rabl-rails/fragment'
 require 'rabl-rails/compiler'
 
 require 'rabl-rails/renderer'

lib/rabl-rails/compiler.rb

@@ -6,6 +6,7 @@ module RablRails
   class Compiler
     def initialize
       @glue_count = 0
+      @cache_count = 0
     end
 
     #
@@ -125,6 +126,17 @@ module RablRails
       @template.merge!(t.source)
     end
     
+    #
+    # cache key: ->(resource) { |resource| resource.cache_key }, expires_in: 1800
+    #
+    def cache(options = {}, &block)
+      return unless block_given?
+      key = options.delete(:key)
+      source = sub_compile { yield }
+      @template[:"_cache#{@cache_count}"] = Fragment.new(key, source, options)
+      @cache_count += 1
+    end
+
     protected
 
     #
@@ -148,11 +160,11 @@ module RablRails
       end
     end
     
-    def sub_compile(data)
+    def sub_compile(data = nil)
       return {} unless block_given?
       old_template, @template = @template, {}
       yield
-      @template.merge!(:_data => data)
+      data ? @template.merge!(:_data => data) : @template
     ensure
       @template = old_template
     end

lib/rabl-rails/fragment.rb

@@ -0,0 +1,42 @@
+require 'active_support/cache'
+
+module RablRails
+  class Fragment
+    attr_reader :compiled_source, :options
+
+    def initialize(key, source, options = {})
+      @key = key
+      @compiled_source = source
+      @options = options
+    end
+
+    def expand_cache_key(data)
+      if @key
+        @key.respond_to?(:call) ? @key.call(data) : @key
+      else
+        ActiveSupport::Cache.expand_cache_key(data, 'rabl')
+      end
+    end
+  end
+end
+
+#
+# cache key: ->(resource) { |resource| resource.cache_key }, expires_in: 1800
+#
+# def cache(options = {}, &block)
+#   return unless block_given?
+#   key = options.delete(:key)
+#   source = sub_compiler { compile_block(&block) }
+#   @template[:"_cache#{cache_count}"] = Fragment.new(key, source, options)
+# end
+
+#
+# when Fragment
+#   render_fragment(value)
+#
+
+# def render_fragment(data, fragment)
+#   Rails.cache.fetch(fragment.expand_cache_key(data), fragment.options) do
+#     render_resource(data, fragment.compiled_source)
+#   end
+# end

lib/rabl-rails/renderers/base.rb

@@ -62,6 +62,12 @@ module RablRails
             else # child
               object.respond_to?(:each) ? render_collection(object, current_value) : render_resource(object, current_value)
             end
+          when Fragment
+            cache_output = Rails.cache.fetch(value.expand_cache_key(data), value.options) do
+              data.respond_to?(:each) ? render_collection(data, value.compiled_source) : render_resource(data, value.compiled_source)
+            end
+            output.merge!(cache_output)
+            next output
           end
           output[key] = out
           output

test/compiler_test.rb

@@ -149,4 +149,14 @@ class CompilerTest < ActiveSupport::TestCase
     assert_equal({ :user => { :_data => :@user, :id => :id } }, t.source)
     assert_equal false, t.data
   end
+  
+  test "cache are compiled to fragment" do
+    t = @compiler.compile_source(%{
+      cache do
+        attributes :name
+      end
+    })
+    assert_instance_of RablRails::Fragment, t.source[:_cache0]
+    assert_equal({ :name => :name }, t.source[:_cache0].compiled_source)
+  end
 end

test/fragment_cache_test.rb

@@ -0,0 +1,4 @@
+require 'test_helper'
+
+class FragmentCacheTest < ActiveSupport::TestCase
+end