Sinatra の initialize と configure はどちらも一回しかコールされない

• 概要
• 環境
• 動作確認用のコード
• before を使う
• Tips

概要

もしリクエストごとに毎回初期化したい場合は before などを使いましょう

環境

• macOS 11.6.2
• Ruby 3.0.3p157
• Sinatra 2.1.0

動作確認用のコード

• vim test.rb

require 'sinatra/base'

class TestWeb < Sinatra::Base
  def initialize()
    super
    puts "initialize"
    @age = (0..100).to_a.sample
  end

  configure do
    puts "configure"
    set :color, ['blue', 'red', 'green'].sample
  end

  get '/' do
    ret = "#{@age.to_s}, #{settings.color}"
    puts ret
    ret
  end
end

• vim config.ru

require './test'

run TestWeb

• bundle exec rackup config.ru
• curl localhost:9292

configure
2022-01-27 10:38:45 +0900 Thin web server (v1.8.1 codename Infinite Smoothie)
2022-01-27 10:38:45 +0900 Maximum connections set to 1024
2022-01-27 10:38:45 +0900 Listening on localhost:9292, CTRL+C to stop
initialize
4, blue
::1 - - [27/Jan/2022:10:38:46 +0900] "GET / HTTP/1.1" 200 7 0.0144
4, blue
::1 - - [27/Jan/2022:10:38:47 +0900] "GET / HTTP/1.1" 200 7 0.0012
4, blue
::1 - - [27/Jan/2022:10:38:48 +0900] "GET / HTTP/1.1" 200 7 0.0011
4, blue
::1 - - [27/Jan/2022:10:38:48 +0900] "GET / HTTP/1.1" 200 7 0.0009
4, blue
::1 - - [27/Jan/2022:10:38:49 +0900] "GET / HTTP/1.1" 200 7 0.0015

ずっと同じ値が返ってくることがわかる

before を使う

• vim test.rb

require 'sinatra/base'

class TestWeb < Sinatra::Base
  def initialize()
    super
    puts "initialize"
    @age = (0..100).to_a.sample
  end

  configure do
    puts "configure"
    set :color, ['blue', 'red', 'green'].sample
  end

  before do
    @age = (0..100).to_a.sample
    @color = ['blue', 'red', 'green'].sample
  end

  get '/' do
    ret = "#{@age.to_s}, #{@color}"
    puts ret
    ret
  end
end

• vim config.ru

require './test'

run TestWeb

• bundle exec rackup config.ru
• curl localhost:9292

configure
2022-01-27 10:40:33 +0900 Thin web server (v1.8.1 codename Infinite Smoothie)
2022-01-27 10:40:33 +0900 Maximum connections set to 1024
2022-01-27 10:40:33 +0900 Listening on localhost:9292, CTRL+C to stop
initialize
9, green
::1 - - [27/Jan/2022:10:40:34 +0900] "GET / HTTP/1.1" 200 8 0.0398
59, blue
::1 - - [27/Jan/2022:10:40:35 +0900] "GET / HTTP/1.1" 200 8 0.0025
86, green
::1 - - [27/Jan/2022:10:40:35 +0900] "GET / HTTP/1.1" 200 9 0.0008
95, green
::1 - - [27/Jan/2022:10:40:36 +0900] "GET / HTTP/1.1" 200 9 0.0016
81, blue
::1 - - [27/Jan/2022:10:40:36 +0900] "GET / HTTP/1.1" 200 8 0.0011
93, blue
::1 - - [27/Jan/2022:10:40:37 +0900] "GET / HTTP/1.1" 200 8 0.0012
72, red
::1 - - [27/Jan/2022:10:40:38 +0900] "GET / HTTP/1.1" 200 7 0.0011

毎回違う

Tips

ちなみに configure ないではインスタンス変数に値を設定できないので set メソッドを使って設定し参照する場合は settings を使います

逆に before では set は使えません
Sinatra のインスタンス変数の扱うは少し面倒です