marcelhuberfoo/cabal-build repository overview

⁠cabal-build

This is a base image for building packages with Haskell's⁠ Cabal⁠. (And pretty much the rest of the Haskell Platform⁠.)

This Dockerfile is based on suitupalex/cabal-build⁠.

⁠Purpose

This docker image builds on top of my minimal Arch Linux marcelhuberfoo/arch⁠ image for the purpose of building projects using Cabal⁠. It provides several features of which some are already present in the base image:

• A non-root user and group docky for executing programs inside the container.
• A umask of 0002 for user docky.
• Exported variables UNAME, GNAME, UID and GID to make use of the user settings from within scripts.
• Timezone (/etc/localtime) is linked to Europe/Zurich, adjust if required in a derived image.
• An external build source folder can be mapped to the volume /data. This volume will be the default working directory.
• The Cabal⁠ bin directory (/home/docky/.cabal/bin) is automatically prepended to the PATH variable.

⁠Usage

This library is useful with simple .cabals from the command line. For example:

docker run --interactive --tty --rm --volume /tmp/my-data:/data marcelhuberfoo/cabal-build

This will execute the default command cabal install -j.

Other commands can also be executed. For example, to update dependencies:

docker run -i -t --rm -v /tmp/my-data:/data marcelhuberfoo/cabal-build cabal update

⁠Permissions

This image provides a user and group docky to run cabal as user docky.

If you map in the /data volume, permissions on the host folder must allow user or group docky to write to it. I recommend adding at least a group docky with GID of 654321 to your host system and change the group of the folder to docky. Don't forget to add yourself to the docky group. The user docky has a UID of 654321 and a GID of 654321 which should not interfere with existing ids on regular Linux systems.

Add user and group docky, group might be sufficient:

groupadd -g 654321 docky
useradd --system --uid 654321 --gid docky --shell '/sbin/nologin' docky

Add yourself to the docky group:

gpasswd --add myself docky

Set group permissions to the entire project directory:

chmod -R g+w /tmp/my-data
chgrp -R docky /tmp/my-data

⁠Dockerfile build

Alternatively, you can create your own Dockerfile that builds on top of this image. This allows you to modify the environment by installing additional software needed, altering the commands to run, etc.

A simple one that just installs another package but leaves the rest of the process alone could look like this:

FROM marcelhuberfoo/cabal-build
MAINTAINER Marcel Huber <[email protected]>
USER root
RUN pacman --sync --noconfirm --noprogressbar --quiet somepackage