概要

M1 MacにRuby on Rails 6のDocker環境を構築する

手順

必要なファイルの用意

Dockerfile

FROM ruby:3.0.2

RUN wget --quiet -O - /tmp/pubkey.gpg https://dl.yarnpkg.com/debian/pubkey.gpg | apt-key add - && \
    echo 'deb http://dl.yarnpkg.com/debian/ stable main' > /etc/apt/sources.list.d/yarn.list
RUN set -x && apt-get update -y -qq && apt-get install -yq nodejs yarn

RUN mkdir /app
WORKDIR /app
COPY Gemfile /app/Gemfile
COPY Gemfile.lock /app/Gemfile.lock
RUN bundle install
COPY . /app

docker-compose.yml

version: '3'
services:
  app:
    build: .
    command: bundle exec rails s -p 3000 -b '0.0.0.0'
    volumes:
      - .:/app
    ports:
      - 3000:3000
    depends_on:
      - db
    tty: true
    stdin_open: true
  db:
    platform: linux/x86_64
    image: mysql:5.7
    volumes:
      - db-volume:/var/lib/mysql
    environment:
      MYSQL_ROOT_PASSWORD: password
volumes:
  db-volume:

Gemfile

source 'https://rubygems.org'
gem 'rails', '6.1.4'

entrypoint.sh

#!/bin/bash
set -e

rm -f /myapp/tmp/pids/server.pid

exec "$@"

空のGemfile.lockを作成

touch Gemfile.lock

アプリ作成コマンド実行

docker-compose run app rails new . --force --database=mysql

DBファイルの修正
config/database.yml
(変更前)

~略~
default: &default
  adapter: mysql2
  encoding: utf8mb4
  pool: <%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>
  username: root
  password:
  host: localhost
~略~

(変更後)

~略~
default: &default
  adapter: mysql2
  encoding: utf8mb4
  pool: <%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>
  username: root
  password: password
  host: db
~略~

build

 docker-compose build

起動

 docker-compose up -d

DB作成

docker-compose run app rails db:create

参考文献

~~https://zenn.dev/tmasuyama1114/articles/rails-docker-6x-how-to~~
→M1 macでは挙動怪しかった