Rebuilding Rails

 1. Zero to “It Works!”

     Just describe the basic gem, and how to use it

     ActiveSupport: some utils like single to plural, time and date support

     ActiveModel: thin wrapper around many different ActiveModel implementations to tell Rails how to use them

     ActiveRecord: ORM

     ActionPack: routing, request through controller, action, render to view

     ActionMailer: email

2. http code: 303 redirect

router的作法, 由rack的env來 找出controller和action

3. autoloading

用to_underscore來找出所要呼叫的controller

再用const_missing和const_get來自動require

4. Rendering Views

render: 先找出view的檔案 filename = File.join 'app', 'views', controller_name, "#{view_name}.html.erb"

     def controller_name

           klass = self.class

           klass = klass.to_s.gsub /Controller$/, ''

           Rulers.to_underscore klass

     end

想從controller傳instance variable到view時需要用到instance_variables和instance_variable_get來倒到view

eruby.result locals.merge(:env => env).merge(view_assigns).merge(other_settings)

    def view_assigns

      hash = {}

      variables = instance_variables

      variables -= [:@env]

      variables.each { |name| hash[name] = instance_variable_get(name) }

      hash

    end

     5. Basic Models

like ActiveRecord

find, all, create, update …..

Exercise 2,3 沒做

     6. Request, Response

using Rackʼs Request and Response objects

Exercise 沒做

     7

     8. Rack Middleware

use ‘use’ add layer by layer