Umkus / docker-scratch

Minimum viable Docker image

Docker scratch image

Minimum viable Docker image(428 bytes compressed).

Allows you to distribute your code in a slim docker image artifact, separate from the execution environment.

Why?

It's convenient in case you package your software into minimalistic data-images, that don't actually being run, but instead expose their content via volumes_from (after the container is created from it). This way you can version your software independently from 3rd party dependencies.

The only difference from the Docker Hub's native scratch image is addition of an empty (<1kb) linux binary that always returns 0 (/bin/true). It is set as image's entrypoint, so it's always safe to run the resulted image and to create container out of it. Without explicitly defining a command or entrypoint.

Usage

Use it just as you would use the native scratch image.

Consider the following usage snippets:

Dockerfile

FROM    umkus/scratch
COPY    . /var/www/
VOLUME  /var/www/

Building

$ docker build -t repo/app --squash .

Docker compose

version: '2'
services:
    fpm:
        image: php
        volumes_from:
            - code
        entrypoint: php bin/console -vvv
    code:
        image: repo/app