開発をするためのディレクトリを作成する

mkdir 自分で開発するアプリの名前

Dockerfileを作成する

touch Dockerfile

Dockerfileの中身を書く

# 使いたいバージョンを決めて{{}}をruby:tag名の形で置き換えてください
# 例: ARG RUBY_VERSION=ruby:3.2.2
ARG RUBY_VERSION={{rubyのimage名:tag名}}
# {{}}を丸ごと使いたいnodeのversionに置き換えてください、小数点以下はいれないでください
# 例: ARG NODE_VERSION=19
ARG NODE_VERSION={{nodeのversion}}

FROM $RUBY_VERSION
ARG RUBY_VERSION
ARG NODE_VERSION
ENV LANG C.UTF-8
ENV TZ Asia/Tokyo
RUN curl -sL https://deb.nodesource.com/setup_${NODE_VERSION}.x | bash - \
&& wget --quiet -O - /tmp/pubkey.gpg https://dl.yarnpkg.com/debian/pubkey.gpg | apt-key add - \
&& echo "deb https://dl.yarnpkg.com/debian/ stable main" | tee /etc/apt/sources.list.d/yarn.list \
&& apt-get update -qq \
&& apt-get install -y build-essential nodejs yarn
RUN mkdir /app
WORKDIR /app
RUN gem install bundler
COPY Gemfile /app/Gemfile
COPY Gemfile.lock /app/Gemfile.lock
COPY yarn.lock /app/yarn.lock
RUN bundle install
RUN yarn install
COPY . /app

compose.ymlを作成する

touch compose.yml

compose.ymlの中身を書く

services:
  db:
    image: postgres:latest
    platform: linux/amd64
    environment:
      TZ: Asia/Tokyo
      POSTGRES_PASSWORD: password
    volumes:
      - postgres_data:/var/lib/postgresql/data
    ports:
      - 5432:5432
  web:
    build: .
    command: bash -c "rm -f tmp/pids/server.pid && bundle exec rails s -p 3000 -b '0.0.0.0'"
    tty: true
    stdin_open: true
    volumes:
      - .:/app
      - bundle_data:/usr/local/bundle:cached
      - node_modules:/app/node_modules
    environment:
      TZ: Asia/Tokyo
    ports:
      - "3000:3000"
    depends_on:
      - db
volumes:
  postgres_data:
  bundle_data:
  node_modules:

Dockerfile内で指定しているファイルを作成する

touch Gemfile Gemfile.lock yarn.lock

Gemfileに使用するRailsのバージョンを書く

# frozen_string_literal: true

source "https://rubygems.org"

gem "rails", "~> 7.0.0"

rails new

docker-compose run --rm --no-deps web rails new . --force --database=mysql --css=bootstrap

・オプションはご自由に。

Overwrite /app/Gemfile? (enter "h" for help) [Ynaqdhm]

と聞かれたらyを入力。

config/database.ymlを編集する

# PostgreSQL. Versions 9.3 and up are supported.
#
# Install the pg driver:
#   gem install pg
# On macOS with Homebrew:
#   gem install pg -- --with-pg-config=/usr/local/bin/pg_config
# On macOS with MacPorts:
#   gem install pg -- --with-pg-config=/opt/local/lib/postgresql84/bin/pg_config
# On Windows:
#   gem install pg
#       Choose the win32 build.
#       Install PostgreSQL and put its /bin directory on your path.
#
# Configure Using Gemfile
# gem "pg"
#
default: &default
  adapter: postgresql
  encoding: unicode
  # For details on connection pooling, see Rails configuration guide
  # https://guides.rubyonrails.org/configuring.html#database-pooling
  pool: <%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>
  host: db
  username: postgres
  password: password

development:
  <<: *default
  database: app_development

  # The specified database role being used to connect to postgres.
  # To create additional roles in postgres see `$ createuser --help`.
  # When left blank, postgres will use the default role. This is
  # the same name as the operating system user running Rails.
  #username: app

  # The password associated with the postgres role (username).
  #password:

  # Connect on a TCP socket. Omitted by default since the client uses a
  # domain socket that doesn't need configuration. Windows does not have
  # domain sockets, so uncomment these lines.
  #host: localhost

  # The TCP port the server listens on. Defaults to 5432.
  # If your server runs on a different port number, change accordingly.
  #port: 5432

  # Schema search path. The server defaults to $user,public
  #schema_search_path: myapp,sharedapp,public

  # Minimum log levels, in increasing order:
  #   debug5, debug4, debug3, debug2, debug1,
  #   log, notice, warning, error, fatal, and panic
  # Defaults to warning.
  #min_messages: notice

# 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: app_test

# As with config/credentials.yml, you never want to store sensitive information,
# like your database password, in your source code. If your source code is
# ever seen by anyone, they now have access to your database.
#
# Instead, provide the password or a full connection URL as an environment
# variable when you boot the app. For example:
#
#   DATABASE_URL="postgres://myuser:mypass@localhost/somedatabase"
#
# If the connection URL is provided in the special DATABASE_URL environment
# variable, Rails will automatically merge its configuration values on top of
# the values provided in this file. Alternatively, you can specify a connection
# URL environment variable explicitly:
#
#   production:
#     url: <%= ENV["MY_APP_DATABASE_URL"] %>
#
# Read https://guides.rubyonrails.org/configuring.html#configuring-a-database
# for a full overview on how database connection configuration can be specified.
#
production:
  <<: *default
  database: app_production
  username: app
  password: <%= ENV["APP_DATABASE_PASSWORD"] %>

Procfile.devを編集する(Option)

web: unset PORT && env RUBY_DEBUG_OPEN=true bin/rails server
js: yarn build --watch
css: yarn build:css --watch

を下記のような形に変更するとデバッグツールが使いやすくなる

js: yarn build --watch
css: yarn build:css --watch

コンテナの立ち上げ

docker compose build

docker compose up

gem・JavaScriptパッケージをインストールする

docker compose up が実行されているターミナルとは別のターミナルで実行。

docker compose run web bundle install

docker compose run web yarn install

データベースの初期化・マイグレーションファイル適応

docker compose up が実行されているターミナルとは別のターミナルで実行。

docker compose exec web rails db:drop

docker compose exec web rails db:create

docker compose exec web rails db:migrate

CSS, JavaScript用のサーバー起動

docker compose up が実行されているターミナルとは別のターミナルで実行。

docker compose exec web bin/dev

ブラウザにて画面が表示されるか確認する

http://localhost:3000/ にアクセス。Railsの初期画面が表示されたら成功。