Quick start for Rails 6 + Webpacker + PostgreSQL on Docker

The repository is based on the article Ruby on Whales: Dockerizing Ruby and Rails development — Martian Chronicles, Evil Martians’ team blog. Note that the article will be continuously updated.

The docker-compose.yml is for building a minimum and configurable development environment for Rails 6 with the following, in a very short time.

• Webpacker
• PostgreSQL

You don't need to tweak the Dockerfile to update gems, packs, databases.

Note that current config is just for building a dev env, not for production container.

Assumed that bundler is included within Ruby 2.7 or later. If you want to specify other version of bundler, uncomment the following:

• BUNDLER_VERSION in docker-compose.yml
• && gem install bundler:$BUNDLER_VERSION in .dockerdev/Dockerfile.

Requirement

• Docker and Docker Compose
• dip for managing docker-compose.yml

Step

Preparation

• Clone this repository to your local environment.
• You can rm -rf .git to recreate the repository for your own usage.
• Adjust the values at the top of docker-compose.yml if needed:

x-var: &APP_IMAGE_TAG
  "my_app:1.0.0"
x-var: &RUBY_VERSION
  "2.7.0-slim-buster"
x-var: &PG_MAJOR
  12
x-var: &POSTGRES
  "postgres:12"
x-var: &NODE_MAJOR
  12
x-var: &YARN_VERSION
  1.21.1
x-var: &BUNDLER_VERSION
  2.1.2

Assumed that bundler is included within Ruby 2.7 or later. If you want to specify other version of bundler, uncomment the following as well:

• BUNDLER_VERSION in docker-compose.yml
• && gem install bundler:$BUNDLER_VERSION in .dockerdev/Dockerfile.

Quick install

• dip provision

Note: --skip-listen option is specified in the command to avoid the issue on macOS: ref: Code is not reloaded in dev with Docker on OS X · Issue #25186 · rails/rails. Perhaps you can remove the option for Linux environments.

Known isue: currently, running db:prepare twice is needed for establishing the initial database connection.

---

That's all. Now you can run rails s command via dip rails s. You don't need to add bundle exec any more.

Misc

• You can see the available dip commands via dip ls.
• .vscode contains a minimum set of conf and extensions. You can discard.
• If you encounter any issues around caching, try checking bootsnap and spring gem.