【Sinatra入門】Ruby+Sinatraで記事投稿アプリケーションを作ろう！（その１）

mkdir Article-Post
cd ./Article-Post
bundle init　# Gemfileを生成

# frozen_string_literal: true

source "https://rubygems.org"

git_source(:github) { |repo_name| "https://github.com/#{repo_name}" }

gem 'activerecord'
gem 'bcrypt'
gem 'mysql2'
gem 'rake'
gem 'redcarpet'
gem 'sinatra'
gem 'sinatra-activerecord'
gem 'sinatra-contrib'
gem 'slim'

sudo bundle install --path vendor/bundle

An error occurred while installing mysql2 (0.5.2), and Bundler cannot continue. Make sure that gem install mysql2 -v '0.5.2' --source 'https://rubygems.org/' succeeds before bundling.

sudo gem install mysql2 -v '0.5.2' --source 'https://rubygems.org/'

 Don't know how to set rpath on your system, if MySQL libraries are not in path mysql2 may not load

ld: library not found for -lssl clang: error: linker command failed with exit code 1 (エラー原因っぽい場所を抜粋) 

bundle config --local build.mysql2 "--with-ldflags=-L/usr/local/opt/openssl/lib --with-cppflags=-I/usr/local/opt/openssl/include"

sudo bundle install --path vendor/bundle

touch app.rb

get '/' do
  'hello world by sinatra'
end

touch config.ru

require 'rubygems'
# bundleに入れたgemを全てrequire
require 'bundler'
Bundler.require
# sinatra-contribのオートリロードしてくれるやつはrequireする必要がある
require 'sinatra/reloader'
# app.rbもrequireする
require './app.rb'

run Sinatra::Application

bundle exec rackup config.ru

.
├── Gemfile
├── Gemfile.lock
├── app.rb
├── config.ru
└── vendor
    └── bundle
        └── ruby

require 'sinatra'

get '/' do
  'hello world by sinatra'
end

bundle exec ruby app.rb

touch Rakefile

require 'sinatra/activerecord'
require 'sinatra/activerecord/rake'

mysql.server start # MySQL起動
mysql -u root # ログイン

mysql> CREATE DATABASE articles4; # articles4という名前のDBを作成
mysql> USE articles4; # それを使うよーと宣言

touch database.yml

development:
  adapter: mysql2
  database: articles4
  host: localhost
  username: root
  password:
  encoding: utf8

# 〜省略〜
require './app.rb'

# 追加↓
# database.ymlを読み込んでくれ〜
ActiveRecord::Base.configurations = YAML.load_file('database.yml')
# developmentを設定
ActiveRecord::Base.establish_connection(:development)
# タイムゾーンを東京にする
Time.zone = 'Tokyo'
ActiveRecord::Base.default_timezone = :local

run Sinatra::Application

require 'sinatra/activerecord'
require 'sinatra/activerecord/rake'

# 上と同じやつ
ActiveRecord::Base.configurations = YAML.load_file('database.yml')
ActiveRecord::Base.establish_connection(:development)
Time.zone = 'Tokyo'
ActiveRecord::Base.default_timezone = :local

bundle exec rake db:create_migration NAME=create_categories

class CreateCategories < ActiveRecord::Migration[5.2]
  def change
  end
end

class CreateCategories < ActiveRecord::Migration[5.2]
  def change
    create_table :categories do |t|
      t.string :name, null: false # stringはVARCHAR(255), null: falseでNOT NULL制約
    end
  end
end

bundle exec rake db:create_migration NAME=create_posts

class CreatePosts < ActiveRecord::Migration[5.2]
  def change
    create_table :posts do |t| # postsがテーブル名
      t.integer :category_id
      t.string  :title, null: false
      t.text    :body,  null: false
      t.string  :thumbnail, null: false

      t.timestamps # これを書くとcreated_atとupdated_atカラムが自動定義される
    end
  end
end

# 起動していない場合
mysql.server start
bundle exec rake db:migrate

mysql -u root # ログイン

# ここからSQL
mysql> use articles4;
mysql> SHOW columns FROM categories;
+-------+--------------+------+-----+---------+----------------+
| Field | Type         | Null | Key | Default | Extra          |
+-------+--------------+------+-----+---------+----------------+
| id    | bigint(20)   | NO   | PRI | NULL    | auto_increment |
| name  | varchar(255) | NO   |     | NULL    |                |
+-------+--------------+------+-----+---------+----------------+
mysql> SHOW columns FROM posts;
+-------------+--------------+------+-----+---------+----------------+
| Field       | Type         | Null | Key | Default | Extra          |
+-------------+--------------+------+-----+---------+----------------+
| id          | bigint(20)   | NO   | PRI | NULL    | auto_increment |
| category_id | int(11)      | YES  |     | NULL    |                |
| title       | varchar(255) | NO   |     | NULL    |                |
| body        | text         | NO   |     | NULL    |                |
| thumbnail   | varchar(255) | NO   |     | NULL    |                |
| created_at  | datetime     | NO   |     | NULL    |                |
| updated_at  | datetime     | NO   |     | NULL    |                |
+-------------+--------------+------+-----+---------+----------------+

.
├── Gemfile
├── Gemfile.lock
├── Rakefile
├── app.rb
├── config.ru
├── database.yml
├── db
│   ├── migrate
│   │   ├── 日付_create_categories.rb
│   │   └── 日付_create_posts.rb
│   └── schema.rb
└── vendor
    └── bundle
        └── ruby

mkdir models
touch models/categories.rb
touch models/posts.rb

class Category < ActiveRecord::Base
end

class Post < ActiveRecord::Base
end

mkdir views
touch views/layout.slim

mkdir helpers

mkdir public
mkdir public/js
mkdir public/css
mkdir public/img

# 〜省略〜
require './app.rb'

# 追加↓
# /models,　/helpers配下のrubyファイルを全てrequireする
Dir[File.dirname(__FILE__) + '/models/*.rb'].each { |f| require f }
Dir[File.dirname(__FILE__) + '/helpers/*.rb'].each { |f| require f }

# database.ymlを読み込み
ActiveRecord::Base.configurations = YAML.load_file('database.yml')
# 〜省略〜

.
├── Gemfile
├── Gemfile.lock
├── Rakefile
├── app.rb
├── config.ru
├── database.yml
├── db
│   ├── migrate
│   │   ├── 日付_create_categories.rb
│   │   └── 日付_create_posts.rb
│   └── schema.rb
├── helpers
├── models
│   ├── categories.rb
│   └── posts.rb
├── public
│   ├── css
│   ├── img
│   └── js
├── vendor
│   └── bundle
│       └── ruby
└── views
    └── layout.slim

gem install racksh

racksh
Rack::Shell v1.0.0 started in development environment.
[1] pry(main)>