go-init

⚠️ Note: This repository is no longer maintained. A maintained fork is available at https://github.com/adambkaplan/go-init.

go-init is a minimal init system with simple lifecycle management heavily inspired by dumb-init.

It is designed to run as the first process (PID 1) inside a container.

It is lightweight (less than 500KB after UPX compression) and statically linked so you don't need to install any dependency.

Download

You can download the latest version on releases page

Why you need an init system

I can't explain it better than Yelp in dumb-init repo, so please read their explanation

Summary:

• Proper signal forwarding
• Orphaned zombies reaping

Why another minimal init system

In addition to init problematic, go-init tries to solve another Docker flaw by adding hooks on start and stop of the main process.

If you want to launch a command before the main process of your container and another one after the main process exit, you can't with Docker, see issue 6982

With go-init you can do that with "pre" and "post" hooks.

Usage

one command

$ go-init -main "my_command param1 param2"

pre-start and post-stop hooks

$ go-init -pre "my_pre_command param1" -main "my_command param1 param2" -post "my_post_command param1"

docker

Example of Dockerfile using go-init:

FROM alpine:latest

COPY go-init /bin/go-init

RUN chmod +x /bin/go-init

ENTRYPOINT ["go-init"]

CMD ["-pre", "echo hello world", "-main", "sleep 5", "-post", "echo I finished my sleep bye"]

Build it:

docker build -t go-init-example

Run it:

docker run go-init-example