Docker for Rails Developers

Compiling Assets with Webpacker

As part of Webpacker, Rails provides the webpack-dev-server binary. This is a small server that runs in the background, automatically compiling our webpack-managed files.

If you were developing locally, this would just be another command you’d issue from your terminal. However, the Docker way is to run this as a separate service in its own container.

Let’s add a new service for it to our docker-compose.yml file:

version: '3'

services:
  web:
    build: .
    ports:
      - "3000:3000"
    volumes:
      - .:/usr/src/app
    env_file:
      - .env/development/web
      - .env/development/database
    environment:
      - WEBPACKER_DEV_SERVER_HOST=webpack_dev_server   

  webpack_dev_server:
 build: ...