DockerでRails6の環境構築

前置き

DockerやGitなどはインストール、初期設定済みのものとします
新規にアプリを作成するときに毎度調べるのも面倒なので備忘録として

環境

• MacOS Monterey(cpu intel)
• Docker -v 20.10.16
• docker-compose v2.3.3

構築内容

• Rails6
• DB postgresql

手順

• 必要なディレクトリとフォルダを用意
  Docments下に作成するアプリのディレクトリを作り、移動

$ mkdir myapp
$ cd myapp

必要なフォルダを作成

$ touch Dockerfile Gemfile Gemfile.lock docker-compose.yml entrypoint.sh

dockerfileに記述

FROM ruby:2.7.4

## nodejsとyarnはwebpackをインストールする際に必要
# yarnパッケージ管理ツールをインストール
RUN curl -sS 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

RUN apt-get update -qq && apt-get install -y nodejs build-essential libpq-dev postgresql-client yarn
WORKDIR /myapp
COPY Gemfile /myapp/Gemfile
COPY Gemfile.lock /myapp/Gemfile.lock
RUN bundle install

RUN yarn install --check-files
RUN bundle exec rails webpacker:install

# Add a script to be executed every time the container starts.
COPY entrypoint.sh /usr/bin/
RUN chmod +x /usr/bin/entrypoint.sh
ENTRYPOINT ["entrypoint.sh"]
EXPOSE 3000

# Configure the main process to run when running the image
CMD ["rails", "server", "-b", "0.0.0.0"]

gemfile

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

entrypoint.sh

#!/bin/bash
set -e

# Remove a potentially pre-existing server.pid for Rails.
rm -f /myapp/tmp/pids/server.pid

# Then exec the container's main process (what's set as CMD in the Dockerfile).
exec "$@"

docker-compose.yml

version: "3.9"
services:
  db:
    image: postgres
    volumes:
      - ./tmp/db:/var/lib/postgresql/data
    environment:
      POSTGRES_PASSWORD: password
  web:
    build: .
    command: bash -c "rm -f tmp/pids/server.pid && bundle exec rails s -p 3000 -b '0.0.0.0'"
    volumes:
      - .:/myapp
    ports:
      - "3000:3000"
    depends_on:
      - db

ターミナル

docker-compose run --no-deps web rails new . --force --database=postgresql
docker-compose run web bundle install
docker-compose build

build出来ず
bundlerとrubyのバージョンを指定し直す

docker-compose run web gem install bundler -v 2.1.2

gemfile.lock

BUNDLED WITH
 2.1.2

Gemfile

ruby '2.7.4'

docker-compose build

config/database.yml

default: &default
  adapter: postgresql
  encoding: unicode
  host: db
  username: postgres
  password: password
  pool: 5

development:
  <<: *default
  database: myapp_development


test:
  <<: *default
  database: myapp_test

ターミナル

docker-compose up -d
docker-compose run web rake db:create

webがexitしてしまう

=> Booting Puma
=> Rails 6.1.6 application starting in development 
=> Run `bin/rails server --help` for more startup options
Exiting
/usr/local/bundle/gems/webpacker-5.4.3/lib/webpacker/configuration.rb:103:in `rescue in load': Webpacker configuration file not found /affiliate_app/config/webpacker.yml. Please run rails webpacker:install Error: No such file or directory @ rb_check_realpath_internal - /affiliate_app/config/webpacker.yml (RuntimeError)

webpackerがインストールされて無いようす

$ docker-compose run web bundle exec rails webpacker:install
$ docker-compose up

localhost:3000で起動を確認

Git

githubにてリポジトリを作成

git init
git add -A
git commit -m "first commit"
git branch -M main
git remote add origin [e-mail]:名前/リポジトリ名
git push -u origin main

init後に、commitに含めたくないものは、init後にgitignoreに記述。
以降、コーディング後には

git add -A
git commit -m "message"
git push

で良い。ブランチとかはまた別で。

参考