Use this as a template for ruby apps:
#-------------------------------------------------------------------------------
# Base
FROM ruby:2.7.2-alpine
SHELL ["/bin/ash", "-c"]
#-------------------------------------------------------------------------------
# Packages
RUN set -exo pipefail && \
\
echo 'Install system packages' && \
apk add --update --no-cache \
build-base \
shadow
#-------------------------------------------------------------------------------
# Workspace
RUN set -exo pipefail && \
\
echo 'Create workspace' && \
mkdir -p /work
WORKDIR /work
#-------------------------------------------------------------------------------
# User
ARG HOST_USER_UID=1000
ARG HOST_USER_GID=1000
RUN set -exo pipefail && \
\
echo 'Create the notroot user and group from host' && \
groupadd -g $HOST_USER_GID notroot && \
useradd -lm -u $HOST_USER_UID -g notroot notroot && \
\
echo 'Set direcotry permissions' && \
chown notroot:notroot /work
#-------------------------------------------------------------------------------
# Gems
COPY --chown=notroot:notroot Gemfile* /work/
USER notroot
RUN set -exo pipefail && \
\
echo 'Install gems' && \
cd /work && \
bundle install --jobs 3 --retry 3
#-------------------------------------------------------------------------------
# Command
CMD ["sh"]
Build it like this:
docker build \
--build-arg=HOST_USER_UID=`id -u` \
--build-arg=HOST_USER_GID=`id -g` \
-t ruby-project \
"$PWD"
Or in docker-compose using:
---
services:
app:
build:
args:
HOST_USER_UID: ${HOST_USER_UID}
HOST_USER_GID: ${HOST_USER_GID}
context: .
dockerfile: ./Dockerfile
And have your host variables defined in your .bash_profile:
HOST_USER_UID=$(id -u)
HOST_USER_GID=$(id -g)
export HOST_USER_UID
export HOST_USER_GID