How to run Webpacker in Docker container

• Build Rails Docker image

$ docker build -t myrails myrails

• Run rails new

$ docker run -it --rm -v $(pwd):/workdir myrails rails new myproject --skip-bundle
$ cd myproject

• Add webpacker and mysql2 to Gemfile

$ echo "gem 'webpacker'" >> Gemfile
$ echo "gem 'mysql2'" >> Gemfile

• Run bundle install

$ docker run -it --rm -v $(pwd):/workdir myrails bundle install --path vendor/bundle

• Run rails webpacker:install

$ docker run -it --rm -v $(pwd):/workdir myrails rails webpacker:install

• Run dev server

$ cd ..
$ docker-compose up -d
$ docker-compose ps
$ docker-compose logs myproject

Visit http://127.0.0.1:3000

• Build your app Docker image

$ docker build -t myapp myproject

• Run your app

$ docker run -d -p 3000:3000 myapp