Jekyll on RVM-installed Ruby

README.md

This Docker image installs RVM and then has it install Ruby before installing the Jekyll gem.

Building a container

$ docker build -t jekyll .

Listing RVM-managed Rubies

$ docker run --rm --it jekyll "rvm list"

Running Jekyll commands

$ docker run --rm --it jekyll "jekyll help"

Running Jekyll commands that touch files

To do this, you'll need to map a host directory path to a mounted path /vol in the container. For example:

% docker run --rm -it --volume $HOME/site:/vol jekyll "jekyll new hello"
Running bundle install in /vol/hello...
  Bundler: Fetching gem metadata from https://rubygems.org/............
  Bundler: Resolving dependencies...
  Bundler: Fetching rexml 3.2.6
  Bundler: Installing rexml 3.2.6
  Bundler: Fetching jekyll-feed 0.17.0
  Bundler: Fetching jekyll-seo-tag 2.8.0
  Bundler: Installing jekyll-feed 0.17.0
  Bundler: Installing jekyll-seo-tag 2.8.0
  Bundler: Fetching minima 2.5.1
  Bundler: Installing minima 2.5.1
  Bundler: Bundle complete! 7 Gemfile dependencies, 33 gems now installed.
  Bundler: Use `bundle info [gemname]` to see where a bundled gem is installed.Don't run Bundler as root. Installing your bundle as root will break this
  Bundler: application for all non-root users on this machine.
New jekyll site installed in /vol/hello.
% ls $HOME/site
hello

Dockerfile

# syntax=docker/dockerfile:1.4
FROM ubuntu:22.04
LABEL org.opencontainers.image.authors="Santoso Wijaya <code@swijaya.com>"

ARG DEBIAN_FRONTEND=noninteractive

RUN <<EOF
  apt-get update -q
  apt-get install -qy --no-install-recommends \
    procps \
    curl \
    ca-certificates \
    gnupg2 \
    build-essential \
    zlib1g-dev \
    wget \
    gpg \
    xz-utils
  apt-get clean
EOF

# Use the bash shell with -l (login) from here on.
# The login behavior is important to trigger RVM's setup scripts.
SHELL [ "/bin/bash", "-l", "-c" ]

# Fetch and install RVM, then use it to install Ruby 3.1.3
RUN <<EOF
  gpg2 --keyserver hkp://keys.gnupg.net --recv-keys D39DC0E3
  curl -sSL https://get.rvm.io | bash -s
  . /etc/profile.d/rvm.sh && rvm install 3.1.3
EOF

RUN <<EOF
  rvm list
  ruby -v
  gem install jekyll bundler
EOF

# If invoking Jekyll commands that touch files, mount them here.
VOLUME /vol
WORKDIR /vol

ENTRYPOINT ["/bin/bash", "-l", "-c"]