RoR创建项目流程

Rails 入门

一个月前在不懂任何rails知识的情况,就已经把这个入门项目搭建成功,足以说明rails on ruby做web开发的简单,经过一个月的学习对rails有了一定的了解,今天趁着周末再来试着搭建一遍,增加自己的认识。更重要的是我们来看看用rails来开发到底方便在哪里？

环境信息

默认已经安装好环境所需要的各种工具

创建新项目

一个好的框架,创建一个项目时，会自动把一些共有的文件都初始化,不需要我们再手动添加。来看看rails怎么创建：

➜  Developer rails new blog      create      create  README.md      create  Rakefile      create  config.ru      create  .gitignore      create  Gemfile      create  app      create  app/assets/config/manifest.js      create  app/assets/javascripts/application.js      create  app/assets/javascripts/cable.js      create  app/assets/stylesheets/application.css      create  app/channels/application_cable/channel.rb      create  app/channels/application_cable/connection.rb      create  app/controllers/application_controller.rb      create  app/helpers/application_helper.rb      create  app/jobs/application_job.rb      create  app/mailers/application_mailer.rb      create  app/models/application_record.rb      create  app/views/layouts/application.html.erb      create  app/views/layouts/mailer.html.erb      create  app/views/layouts/mailer.text.erb      create  app/assets/images/.keep      create  app/assets/javascripts/channels      create  app/assets/javascripts/channels/.keep      create  app/controllers/concerns/.keep      create  app/models/concerns/.keep      create  bin      create  bin/bundle      create  bin/rails      create  bin/rake      create  bin/setup      create  bin/update      create  config      create  config/routes.rb      create  config/application.rb      create  config/environment.rb      create  config/secrets.yml      create  config/cable.yml      create  config/puma.rb      create  config/spring.rb      create  config/environments      create  config/environments/development.rb      create  config/environments/production.rb      create  config/environments/test.rb      create  config/initializers      create  config/initializers/application_controller_renderer.rb      create  config/initializers/assets.rb      create  config/initializers/backtrace_silencers.rb      create  config/initializers/cookies_serializer.rb      create  config/initializers/cors.rb      create  config/initializers/filter_parameter_logging.rb      create  config/initializers/inflections.rb      create  config/initializers/mime_types.rb      create  config/initializers/new_framework_defaults.rb      create  config/initializers/session_store.rb      create  config/initializers/wrap_parameters.rb      create  config/locales      create  config/locales/en.yml      create  config/boot.rb      create  config/database.yml      create  db      create  db/seeds.rb      create  lib      create  lib/tasks      create  lib/tasks/.keep      create  lib/assets      create  lib/assets/.keep      create  log      create  log/.keep      create  public      create  public/404.html      create  public/422.html      create  public/500.html      create  public/apple-touch-icon-precomposed.png      create  public/apple-touch-icon.png      create  public/favicon.ico      create  public/robots.txt      create  test/fixtures      create  test/fixtures/.keep      create  test/fixtures/files      create  test/fixtures/files/.keep      create  test/controllers      create  test/controllers/.keep      create  test/mailers      create  test/mailers/.keep      create  test/models      create  test/models/.keep      create  test/helpers      create  test/helpers/.keep      create  test/integration      create  test/integration/.keep      create  test/test_helper.rb      create  tmp      create  tmp/.keep      create  tmp/cache      create  tmp/cache/assets      create  vendor/assets/javascripts      create  vendor/assets/javascripts/.keep      create  vendor/assets/stylesheets      create  vendor/assets/stylesheets/.keep      remove  config/initializers/cors.rb         run  bundle installFetching gem metadata from https://rubygems.org/Fetching version metadata from https://rubygems.org/Fetching dependency metadata from https://rubygems.org/Resolving dependencies.....Using rake 11.2.2Using concurrent-ruby 1.0.2Using i18n 0.7.0Using minitest 5.9.0Using thread_safe 0.3.5Using builder 3.2.2Using erubis 2.7.0Using mini_portile2 2.1.0Using pkg-config 1.1.7Using rack 2.0.1Using nio4r 1.2.1Using websocket-extensions 0.1.2Using mime-types-data 3.2016.0521Your user account isn't allowed to install to the system Rubygems.  You can cancel this installation and run:      bundle install --path vendor/bundle  to install the gems into ./vendor/bundle/, or you can enter your password  and install the bundled gems to Rubygems using sudo.  Password:Installing arel 7.1.1Using bundler 1.12.5Using byebug 9.0.5Using coffee-script-source 1.10.0Using execjs 2.7.0Using method_source 0.8.2Using thor 0.19.1Using debug_inspector 0.0.2Installing ffi 1.9.14 with native extensionsUsing multi_json 1.12.1Using rb-fsevent 0.9.7Installing puma 3.6.0 with native extensionsUsing sass 3.4.22Using tilt 2.0.5Using spring 1.7.2Using sqlite3 1.3.11Using turbolinks-source 5.0.0Using tzinfo 1.2.2Using nokogiri 1.6.8Using rack-test 0.6.3Using sprockets 3.7.0Using websocket-driver 0.6.4Using mime-types 3.1Using coffee-script 2.4.1Installing uglifier 3.0.1Using rb-inotify 0.9.7Installing turbolinks 5.0.1Using activesupport 5.0.0Using loofah 2.0.3Using mail 2.6.4Using listen 3.0.8Using rails-dom-testing 2.0.1Installing globalid 0.3.7Using activemodel 5.0.0Using jbuilder 2.6.0Using rails-html-sanitizer 1.0.3Using spring-watcher-listen 2.0.0Using activejob 5.0.0Using activerecord 5.0.0Using actionview 5.0.0Using actionpack 5.0.0Using actioncable 5.0.0Using actionmailer 5.0.0Using railties 5.0.0Using sprockets-rails 3.1.1Using coffee-rails 4.2.1Using jquery-rails 4.1.1Using web-console 3.3.1Using rails 5.0.0Using sass-rails 5.0.6Bundle complete! 15 Gemfile dependencies, 63 gems now installed.Use `bundle show [gemname]` to see where a bundled gem is installed.         run  bundle exec spring binstub --all* bin/rake: spring inserted* bin/rails: spring inserted

这一个命令就已经把所有项目目录文件创建完毕,且安装好所有的依赖,回头想想gradle创建项目的过程,先创建项目，再添加依赖jar包，至少两个命令，所以看看rails on ruby就知道有多爽了。

目录

➜  blog tree.├── Gemfile├── Gemfile.lock├── README.md├── Rakefile├── app│   ├── assets│   │   ├── config│   │   │   └── manifest.js│   │   ├── images│   │   ├── javascripts│   │   │   ├── application.js│   │   │   ├── cable.js│   │   │   └── channels│   │   └── stylesheets│   │       └── application.css│   ├── channels│   │   └── application_cable│   │       ├── channel.rb│   │       └── connection.rb│   ├── controllers│   │   ├── application_controller.rb│   │   └── concerns│   ├── helpers│   │   └── application_helper.rb│   ├── jobs│   │   └── application_job.rb│   ├── mailers│   │   └── application_mailer.rb│   ├── models│   │   ├── application_record.rb│   │   └── concerns│   └── views│       └── layouts│           ├── application.html.erb│           ├── mailer.html.erb│           └── mailer.text.erb├── bin│   ├── bundle│   ├── rails│   ├── rake│   ├── setup│   ├── spring│   └── update├── config│   ├── application.rb│   ├── boot.rb│   ├── cable.yml│   ├── database.yml│   ├── environment.rb│   ├── environments│   │   ├── development.rb│   │   ├── production.rb│   │   └── test.rb│   ├── initializers│   │   ├── application_controller_renderer.rb│   │   ├── assets.rb│   │   ├── backtrace_silencers.rb│   │   ├── cookies_serializer.rb│   │   ├── filter_parameter_logging.rb│   │   ├── inflections.rb│   │   ├── mime_types.rb│   │   ├── new_framework_defaults.rb│   │   ├── session_store.rb│   │   └── wrap_parameters.rb│   ├── locales│   │   └── en.yml│   ├── puma.rb│   ├── routes.rb│   ├── secrets.yml│   └── spring.rb├── config.ru├── db│   └── seeds.rb├── lib│   ├── assets│   └── tasks├── log├── public│   ├── 404.html│   ├── 422.html│   ├── 500.html│   ├── apple-touch-icon-precomposed.png│   ├── apple-touch-icon.png│   ├── favicon.ico│   └── robots.txt├── test│   ├── controllers│   ├── fixtures│   │   └── files│   ├── helpers│   ├── integration│   ├── mailers│   ├── models│   └── test_helper.rb├── tmp│   └── cache│       └── assets└── vendor    └── assets        ├── javascripts        └── stylesheets44 directories, 57 files

初始化的项目包含44个目录和57个文件,详细解释见参考文档

启动

经过上面一个命令我们的helloworld项目就已经创建完成了,现在启动

➜  blog rails s=> Booting Puma=> Rails 5.0.0 application starting in development on http://localhost:3000=> Run `rails server -h` for more startup optionsPuma starting in single mode...* Version 3.6.0 (ruby 2.3.0-p0), codename: Sleepy Sunday Serenity* Min threads: 5, max threads: 5* Environment: development* Listening on tcp://localhost:3000Use Ctrl-C to stop

就这样一个项目就创建了并启动成功了。是不是so easy!

添加controller

我目前在做php开发，php框架里创建一个controller是这样的，首先在controller的main文件，添加一个路由。然后在actions里添加一个处理请求的action，然后在model里创建一个page和data还有一个dao，这这些都是手动创建过程，且你必须按照人家框架的要求定义命名规范，那既然框架都已经有要求来规范你的命名，那么框架为何不直接创建呢？

所以，rails就做到了，来看看rails如何一条命令完成上面所有的操作：

➜  blog rails generate controller welcome indexRunning via Spring preloader in process 70093      create  app/controllers/welcome_controller.rb       route  get 'welcome/index'      invoke  erb      create    app/views/welcome      create    app/views/welcome/index.html.erb      invoke  test_unit      create    test/controllers/welcome_controller_test.rb      invoke  helper      create    app/helpers/welcome_helper.rb      invoke    test_unit      invoke  assets      invoke    coffee      create      app/assets/javascripts/welcome.coffee      invoke    scss      create      app/assets/stylesheets/welcome.scss

看这一条命令创建了多少文件：

• controller文件:welcome_controller.rb
• 路由添加welcome/index，get请求
• 在view中添加welcome文件夹和html文件index.html.erb
• 单测文件welcome_controller_test.rb
• 帮助文件welcome_helper.rb
• js文件和css文件

这个功能很好的诠释了约定优于配置。

下面我们继续

主页设置

在config/routes.rb中添加如下语句：

root 'welcome#index'

root这个关键字就是定义了网页的根页面，上面这个用法是告诉服务器，去找welcome这个controller的index的方法，看下面的welcome_controller.rb文件，index方法啥也没有啊，

这又是一个约定，约定说默认跳转到welcome/index.html.erb页面

现在我们来访问一下localhost:3000：

就是这么简单。

路由查看

要想知道我们有多少路由信息，可以通过rake routes命令查看

➜  blog rake routes       Prefix Verb URI Pattern              Controller#Action         root GET  /                        welcome#indexwelcome_index GET  /welcome/index(.:format) welcome#index

然后我们再来一个约定由于配置的体现，在config/routes.rb中添加一行

resources :articles

这个时候我们再看看有多少路由:

➜  blog rake routes       Prefix Verb   URI Pattern                  Controller#Action     articles GET    /articles(.:format)          articles#index              POST   /articles(.:format)          articles#create  new_article GET    /articles/new(.:format)      articles#new edit_article GET    /articles/:id/edit(.:format) articles#edit      article GET    /articles/:id(.:format)      articles#show              PATCH  /articles/:id(.:format)      articles#update              PUT    /articles/:id(.:format)      articles#update              DELETE /articles/:id(.:format)      articles#destroy         root GET    /                            welcome#indexwelcome_index GET    /welcome/index(.:format)     welcome#index

那些多出来的都是默认创建出来的。

创建模型

➜  blog rails generate model ArticleRunning via Spring preloader in process 79757      invoke  active_record      create    db/migrate/20160809092044_create_articles.rb      create    app/models/article.rb      invoke    test_unit      create      test/models/article_test.rb      create      test/fixtures/articles.yml

生成了一个迁移文件,以时间戳标识
还有model文件article.rb
测试文件:test/models/article_test.rb
测试模拟数据文件:test/fixtures/articles.yml

执行迁移

➜  blog rake db:migrate== 20160809092501 CreateArticles: migrating ===================================-- create_table(:articles)   -> 0.0012s== 20160809092501 CreateArticles: migrated (0.0013s) ==========================

默认用的sqlite数据库,我们去查看一下数据库表。

conf/database.yml中定义了数据库相关信息

default: &default  adapter: sqlite3  pool: 5  timeout: 5000development:  <<: *default  database: db/development.sqlite3# Warning: The database defined as "test" will be erased and# re-generated from your development database when you run "rake".# Do not set this db to the same as development or production.test:  <<: *default  database: db/test.sqlite3production:  <<: *default  database: db/production.sqlite3

可以看出我们开发环境的数据库为db/development.sqlite3，我们进去看看：

➜  blog sqlite3 db/development.sqlite3SQLite version 3.8.10.2 2015-05-20 18:17:19Enter ".help" for usage hints.sqlite> .tablesar_internal_metadata  articles              schema_migrationssqlite> .schema articlesCREATE TABLE "articles" ("id" INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, "created_at" datetime NOT NULL, "updated_at" datetime NOT NULL);