First pass at Rack::Cache

Author: wycats

actionpack/actionpack.gemspec

@@ -19,13 +19,15 @@ Gem::Specification.new do |s|
 
   s.has_rdoc = true
 
-  s.add_dependency('activesupport', version)
-  s.add_dependency('activemodel',   version)
-  s.add_dependency('builder',       '~> 2.1.2')
-  s.add_dependency('i18n',          '~> 0.4.1')
-  s.add_dependency('rack',          '~> 1.2.1')
-  s.add_dependency('rack-test',     '~> 0.5.4')
-  s.add_dependency('rack-mount',    '~> 0.6.13')
-  s.add_dependency('tzinfo',        '~> 0.3.23')
-  s.add_dependency('erubis',        '~> 2.6.6')
+  s.add_dependency('activesupport',    version)
+  s.add_dependency('activemodel',      version)
+  s.add_dependency('rack-cache',       '~> 0.5.2')
+  s.add_dependency('rack-cache-purge', '~> 0.0.1')
+  s.add_dependency('builder',          '~> 2.1.2')
+  s.add_dependency('i18n',             '~> 0.4.1')
+  s.add_dependency('rack',             '~> 1.2.1')
+  s.add_dependency('rack-test',        '~> 0.5.4')
+  s.add_dependency('rack-mount',       '~> 0.6.13')
+  s.add_dependency('tzinfo',           '~> 0.3.23')
+  s.add_dependency('erubis',           '~> 2.6.6')
 end

actionpack/lib/action_dispatch/http/rack_cache.rb

@@ -0,0 +1,67 @@
+require "rack/cache"
+require "rack/cache/context"
+require "active_support/cache"
+
+module ActionDispatch
+  class RailsMetaStore < Rack::Cache::MetaStore
+    def self.resolve(uri)
+      new
+    end
+
+    # TODO: Finally deal with the RAILS_CACHE global
+    def initialize(store = RAILS_CACHE)
+      @store = store
+    end
+
+    def read(key)
+      @store.read(key) || []
+    end
+
+    def write(key, value)
+      @store.write(key, value)
+    end
+
+    def purge(key)
+      @store.delete(key)
+      nil
+    end
+
+    ::Rack::Cache::MetaStore::RAILS = self
+  end
+
+  class RailsEntityStore < Rack::Cache::EntityStore
+    def self.resolve(uri)
+      new
+    end
+
+    def initialize(store = RAILS_CACHE)
+      @store = store
+    end
+
+    def exist?(key)
+      @store.exist?(key)
+    end
+
+    def open(key)
+      @store.read(key)
+    end
+
+    def read(key)
+      body = open(key)
+      body.join if body
+    end
+
+    def write(body)
+      buf = []
+      key, size = slurp(body) { |part| buf << part }
+      @store.write(key, buf)
+      [key, size]
+    end
+
+    def purge(key)
+      @store.delete(key)
+    end
+
+    ::Rack::Cache::EntityStore::RAILS = self
+  end
+end

actionpack/lib/action_dispatch/railtie.rb

@@ -9,6 +9,7 @@ class Railtie < Rails::Railtie
     config.action_dispatch.show_exceptions = true
     config.action_dispatch.best_standards_support = true
     config.action_dispatch.tld_length = 1
+    config.action_dispatch.rack_cache = {:metastore => "rails:/", :entitystore => "rails:/", :verbose => true}
 
     initializer "action_dispatch.configure" do |app|
       ActionDispatch::Http::URL.tld_length = app.config.action_dispatch.tld_length

railties/lib/rails/application.rb

@@ -147,6 +147,9 @@ def config
 
     def default_middleware_stack
       ActionDispatch::MiddlewareStack.new.tap do |middleware|
+        require "action_dispatch/http/rack_cache" if config.action_dispatch.rack_cache
+
+        middleware.use ::Rack::Cache, config.action_dispatch.rack_cache if config.action_dispatch.rack_cache
         middleware.use ::ActionDispatch::Static, config.static_asset_paths if config.serve_static_assets
         middleware.use ::Rack::Lock if !config.allow_concurrency
         middleware.use ::Rack::Runtime

railties/test/application/middleware_test.rb

@@ -19,6 +19,7 @@ def app
       boot!
 
       assert_equal [
+        "Rack::Cache",
         "ActionDispatch::Static",
         "Rack::Lock",
         "ActiveSupport::Cache::Strategy::LocalCache",
@@ -81,24 +82,24 @@ def app
     test "insert middleware after" do
       add_to_config "config.middleware.insert_after ActionDispatch::Static, Rack::Config"
       boot!
-      assert_equal "Rack::Config", middleware.second
+      assert_equal "Rack::Config", middleware.third
     end
 
     test "RAILS_CACHE does not respond to middleware" do
       add_to_config "config.cache_store = :memory_store"
       boot!
-      assert_equal "Rack::Runtime", middleware.third
+      assert_equal "Rack::Runtime", middleware.fourth
     end
 
     test "RAILS_CACHE does respond to middleware" do
       boot!
-      assert_equal "Rack::Runtime", middleware.fourth
+      assert_equal "Rack::Runtime", middleware.fifth
     end
 
     test "insert middleware before" do
       add_to_config "config.middleware.insert_before ActionDispatch::Static, Rack::Config"
       boot!
-      assert_equal "Rack::Config", middleware.first
+      assert_equal "Rack::Config", middleware.second
     end
 
     # x_sendfile_header middleware