Ruby on Rails Tutorial

Ruby on RailsTutorial

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Ruby 2.0.0

Rails 4.0.0

Bundler 1.3.5

SQLite 3.7.2

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Rails

% mkdir -p tutorial% cd tutorial% bundle init% vi Gemfile% bundle install --path vendor/bundle

Gemfilesource "https://rubygems.org"

gem "rails"

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% bundle exec rails new . --skip-bundle

conflict GemfileOverwrite /path/to/tutorial/Gemfile? (enter "h" for help) [Ynaqdh] Enter()

-T test/unit

-d mysql/postgresqlSQLite

--skip-bundle bundle init

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% vi Gemfile% bundle

# See https://github.com/sstephenson/execjs#readme for more supported runtimes# gem 'therubyracer', platforms: :ruby

Gemfile

% export PATH=`pwd`/bin:$PATH% rails -v

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app

app

assets image/stylesheet/javascript

appcontrollers

app helpers appmailers

app

models

app

views bin bundle/rails/rakebundle/rails/rake

config db /SQLite DB/SQLite DBlib /Rake/Rakelog

public WebDocumentRootWebDocumentRoottest (RSpecspec)(RSpecspec)tmp TempTemp

vendor 6

rails/rake

rails server WEBrickrails console Railsrails dbconsole DBrails runner Rails

rake db:create rake db:migrate rake db:rollback rake routes rake assets:precompile

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% rails s

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Scaffold% rails generate scaffold blog title:string body:text% rake db:migrate

CRUDmodel/scaffold

`rake db:migrate`DB

assets/controller/helper/model/view

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% rails g model : :

% rails g controller

% rails g migration

db/migrate/YYYYmmddHHMMSS_task.rb`rake db:migrate`/

assets/controller/helper/view

modelstring/text/integer/float/boolean/date/time/timestampDBDB

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db/migrate/

`rake db:migrate`DB

`rake db:rollback`

schema_migrations

class CreateBlogs < ActiveRecord::Migration def change create_table :blogs do |t| t.string :title t.text :body

t.timestamps end endend

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router(routes.rb)

DBServer

controllers(controllers/*.rb)

models(models/*.rb)

views(views/*/

*.html.erb)

request routing

sql

response

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app/models/blog.rb

class Blog < ActiveRecord::Baseend

//DB

% rails c> blog = Blog.new> blog.title = "test title"> blog.body = "test body"> blog.save # blogs> blogs = Blog.all # blogs> blogs.each {|b| puts b.title} # title> blog = Blog.find(1) # blogsid1> puts blog.title # title> blog.destroy # blogs

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Tutorial::Application.routes.draw do resources :blogsend

config/routes.rb

% rake routes Prefix Verb URI Pattern Controller#Action blogs GET /blogs(.:format) blogs#index POST /blogs(.:format) blogs#create new_blog GET /blogs/new(.:format) blogs#newedit_blog GET /blogs/:id/edit(.:format) blogs#edit blog GET /blogs/:id(.:format) blogs#show PATCH /blogs/:id(.:format) blogs#update PUT /blogs/:id(.:format) blogs#update DELETE /blogs/:id(.:format) blogs#destroy

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Tutorial::Application.routes.draw do controller :blogs do # HTTPMethod URI, to: ExecMethod, as: :Prefix # GET /index => BlogsController#index (index_path) get :index, to: :index, as: :index

# POST /create => BlogsController#create (create_path) post :create, to: :create, as: :create

# GET / => BlogsController#root (root_path) get :root, to: "blogs#root" endend

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class BlogsController < ApplicationController before_action :set_blog, only: [:show, :edit, :update, :destroy]

def index @blogs = Blog.all end

def new @blog = Blog.new end

private def set_blog @blog = Blog.find(params[:id]) end

def blog_params params.require(:blog).permit(:title, :body) endend

app/controller/blogs_controller.rb

view16

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#index@blogsblogsview

#new@blogBlogview

#showbefore_actionset_blogview

#editshowbefore_actionset_blogview

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3class BlogsController < ApplicationController def create @blog = Blog.new(blog_params)

respond_to do |format| if @blog.save format.html { redirect_to @blog, notice: 'Blog was successfully created.' } format.json { render action: 'show', status: :created, location: @blog } else format.html { render action: 'new' } format.json { render json: @blog.errors, status: :unprocessable_entity } end end endend

Blogstrong parameter@blog@blog.save(DB)newview

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class BlogsController < ApplicationController def update respond_to do |format| if @blog.update(blog_params) format.html { redirect_to @blog, notice: 'Blog was successfully updated.' } format.json { head :no_content } else format.html { render action: 'edit' } format.json { render json: @blog.errors, status: :unprocessable_entity } end end endend

before_actionset_blog@blog.updatecreatestrong parametereditview

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5class BlogsController < ApplicationController def destroy @blog.destroy respond_to do |format| format.html { redirect_to blogs_url } format.json { head :no_content } end endend

before_actionset_blog@blog.destroy

`respond_to {|format| ...}`format

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Tutorial true %> true %>

HTMLlayoutviewHTMLruby()()

app/views/layouts/application.html.erb

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Editing blog

|

`render``redirect_to`app/views//.html.erb(formathtml)edit.html.erb`render`

app/views/blogs/edit.html.erb

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% vi Gemfile% bundle

# gem "passwd"

Gemfile

Gemfile`require`(grouprequirefalse)

2.bundle/configbundle

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% rails g controller sessions

/Sessions

Tutorial::Application.routes.draw do resources :blogs

# controller :sessions do get :login, to: :new, as: :new_session post :login, to: :create, as: :create_session get :logout, to: :destroy, as: :delete_session endend

config/routes.rb

% rake routes... new_session GET /login(.:format) sessions#newcreate_session POST /login(.:format) sessions#createdelete_session GET /logout(.:format) sessions#destroy

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()app/views/sessions/new.html.erb

class SessionsController < ApplicationController def create render text: "login" end def destroy render text: "logout" endend

SessionsControllercreate/destroyapp/controllers/sessions_controller.rb

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% rails g model user email:string salt:string password:string% rake db:migrate

class User < ActiveRecord::Base include Passwd::ActiveRecord define_columnend

Userapp/models/user.rb

% rails c> user = User.new> user.email = "foo@example.com"> user.set_password("secret")> user.save> puts password

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class SessionsController < ApplicationController def create @user = User.authenticate(params[:email], params[:password]) if @user session[:user] = @user.id redirect_to blogs_path else flash.now[:alert] = "Email or password is incorrect." render action: :new end end def destroy session[:user] = nil redirect_to blogs_path endend

/app/controllers/session_controller.rb

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class ApplicationController < ActionController::Base protect_from_forgery with: :exception

# def require_logged_in if session[:user].present? begin @user = User.find(session[:user]) rescue ActiveRecord::RecordNotFound reset_session end end redirect_to create_session_path unless @user endend

ApplicationControllerapp/controllers/application_controller.rb

application_controller.rb

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class BlogsController < ApplicationController before_action :set_blog, only: [:show, :edit, :update, :destroy] # before_action :require_logged_in, only: [:new, :edit, :create, :update, :destroy]

...end

new/edit/create/update/destroy

before_action`require_logged_in`

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