Ruby Docker Container Images

Table of Contents

• Docker Images
  • -dev
  • -dev-macos
  • Supported architectures
• Environment Variables
• Build arguments
• Changelog
• Gems
• HTTP server
  • Puma (default)
  • Unicorn
• Crond
• SSHD
• Adding SSH key
• Complete Ruby stack
• Orchestration Actions

Docker Images

❗For better reliability we release images with stability tags (wodby/ruby:4-X.X.X) which correspond to git tags. We strongly recommend using images only with stability tags.

About images:

• All images are based on Alpine Linux
• Base image: ruby
• GitHub actions builds
• Docker Hub

Supported tags and respective Dockerfile links:

• 4.0, 4, latest (Dockerfile)
• 3.4, 3 (Dockerfile)
• 3.3 (Dockerfile)
• 4.0-dev, 4-dev, dev (Dockerfile)
• 3.4-dev, 3-dev (Dockerfile)
• 3.3-dev (Dockerfile)
• 4.0-dev-macos, 4-dev-macos (Dockerfile)
• 3.4-dev-macos, 3-dev-macos (Dockerfile)
• 3.3-dev-macos (Dockerfile)

-dev

Images with -dev tag have the following additions:

• sudo allowed for all commands for wodby user
• dev package added for additional native extensions compilation
• nodejs package added (required by rails)

-dev-macos

Same as -dev but the default user/group wodby has uid/gid 501/20 to match the macOS default user/group ids.

Supported architectures

All images built for linux/amd64, -dev-macos images additionally built for linux/arm64

Environment Variables

Variable	Default value
GIT_USER_EMAIL	wodby@example.com
GIT_USER_NAME	wodby
PUMA_DIRECTORY	/usr/src/app
PUMA_ENVIRONMENT	development
PUMA_PRELOAD_APP
PUMA_PRUNE_BUNDLER
PUMA_QUIET
PUMA_RACKUP	/usr/src/app/config.ru
PUMA_TAG
PUMA_THREADS	0, 16
PUMA_WORKER_BOOT_TIMEOUT	60
PUMA_WORKER_TIMEOUT	60
PUMA_WORKERS	2
RAILS_ENV	development
SSH_DISABLE_STRICT_KEY_CHECKING
SSH_PRIVATE_KEY
SSHD_GATEWAY_PORTS	no
SSHD_HOST_KEYS_DIR	/etc/ssh
SSHD_LOG_LEVEL	INFO
SSHD_PASSWORD_AUTHENTICATION	no
SSHD_PERMIT_USER_ENV	no
SSHD_USE_DNS	yes
UNICORN_CHECK_CLIENT_CONNECTION	false
UNICORN_DEBUG
UNICORN_PRELOAD_APP	true
UNICORN_RUN_ONCE	true
UNICORN_TIMEOUT	30
UNICORN_WORKER_PROCESSES	4
UNICORN_WORKING_DIRECTORY	/usr/src/app

Build arguments

Argument	Default value
RUBY_DEV
WODBY_GROUP_ID	1000
WODBY_USER_ID	1000

Change WODBY_USER_ID and WODBY_GROUP_ID mainly for local dev version of images, if it matches with existing system user/group ids the latter will be deleted.

Changelog

Changes per stability tag reflected in git tags description under releases.

Gems

To install gems with native extensions use -dev image variants that contain required dev packages.

HTTP server

Puma

Puma is the default HTTP server, you can configure it via PUMA_ env vars.

Unicorn

To use Unicorn as your HTTP server override the default container command to /etc/init.d/unicorn. You can configure it via UNICORN_ env vars.

Crond

You can run Crond with this image changing the command to sudo -E crond -f -d 0 and mounting a crontab file to ./crontab:/etc/crontabs/wodby. Example crontab file contents:

# min	hour	day	month	weekday	command
*/1	*	*	*	*	echo "test" > /mnt/files/cron

SSHD

You can run SSHD with this image by changing the command to sudo /usr/sbin/sshd -De and mounting authorized public keys to /home/wodby/.ssh/authorized_keys

Adding SSH key

You can add a private SSH key to the container by mounting it to /home/wodby/.ssh/id_rsa

Complete Ruby stack

See https://github.com/wodby/docker4ruby

Orchestration Actions

Usage:

make COMMAND [params ...]

commands:
    check-ready [host max_try wait_seconds delay_seconds]
    files-import source
    files-link public_dir