minimum-rack-cnb

This repository contains instruction how to build image without Dockerfile (a bare minimum Rack app) using Cloud Native Buildpack.

Getting started

Usage

This buildpack is currently intended to be used with the heroku builder heroku/pack:18 via pack.

Locally

Build your app

git clone git@github.com:peco8/minimum-rack-cnb.git
cd minimum-rack-cnb
pack build sample \
     --builder heroku/buildpacks:18
     --path .

Quick test

docker run --rm -e PORT=8080 -p 8080:8080 sample
curl -s http://0.0.0.0:8080

GithubActions (CI)

Container images should be built in CI environment, not local. In this repo, we already have CI environment using GithubActions.

Push and Build

Fork and clone this repo locally
cd minimum-rack-cnb
git commit --allow-empty
git push origin master

Pull

docker pull docker.pkg.github.com/<USERNAME>/minimum-rack-cnb/sample:latest

Quick test

docker run --rm -e PORT=8080 -p 8080:8080 docker.pkg.github.com/<USERNAME>/minimum-rack-cnb/sample