Dockerfile

FROM ruby:3.2.2-alpine AS assets
RUN addgroup app --gid 1000
RUN adduser -SD -u 1000 --shell /bin/bash --home /home/app app app
RUN chown -R app:app /usr/local/bundle
COPY --chown=app:app . /home/app/admin
ENV RAILS_ENV=production
ENV HOME=/home/app
RUN apk add --no-cache libpq-dev tzdata gettext shared-mime-info libc6-compat && \
    apk add --no-cache --virtual .build-tools git build-base curl-dev nodejs yarn && \
    cd /home/app/admin && \
    BUNDLER_VERSION=$(grep -A 1 "BUNDLED WITH" Gemfile.lock | tail -n 1 | awk '{$1=$1};1') && \
    gem install bundler:$BUNDLER_VERSION invoker && \
    bundle config set without 'test development' && \
    bundle config set with 'assets production' && \
    bundle config set deployment 'true' && \
    bundle install --no-cache --jobs=5 --retry=3 && \
    bundle exec rails assets:precompile SECRET_KEY_BASE=doesntmatter && \
    chown -R app:app /usr/local/bundle && \
    apk del .build-tools

FROM ruby:3.2.2-alpine

RUN addgroup app --gid 1000
RUN adduser -SD -u 1000 --shell /bin/bash --home /home/app app app


ARG APPVERSION=unknown
ARG APP_BUILD_DATE=unknown
ARG APP_GIT_COMMIT=unknown
ARG APP_BUILD_TAG=unknown

# Setting up ping.json variables
ENV APPVERSION ${APPVERSION}
ENV APP_BUILD_DATE ${APP_BUILD_DATE}
ENV APP_GIT_COMMIT ${APP_GIT_COMMIT}
ENV APP_BUILD_TAG ${APP_BUILD_TAG}

EXPOSE 8080

COPY --chown=app:app . /home/app/admin
COPY --from=assets --chown=app:app /home/app/admin/public/assets /home/app/admin/public/assets
#COPY --from=assets --chown=app:app /home/app/admin/vendor/bundle /home/app/admin/vendor/bundle
RUN chown -R app:app /usr/local/bundle
RUN apk add --no-cache libpq-dev tzdata gettext shared-mime-info libc6-compat curl-dev bash && \
    apk add --no-cache postgresql-client~=11.12 --repository=http://dl-cdn.alpinelinux.org/alpine/v3.10/main && \
    apk add --no-cache --virtual .build-tools git build-base && \
    cd /home/app/admin && \
    BUNDLER_VERSION=$(grep -A 1 "BUNDLED WITH" Gemfile.lock | tail -n 1 | awk '{$1=$1};1') && \
    gem install bundler:$BUNDLER_VERSION invoker && \
    bundle config set without 'test development assets' && \
    bundle config set with 'production' && \
    bundle config set deployment 'true' && \
    bundle install --no-cache --jobs=5 --retry=3 && \
    apk del .build-tools && \
    chown -R app:app /usr/local/bundle && \
    chown -R app:app /home/app/admin/vendor/bundle && \
    mkdir -p /home/app/admin/tmp && \
    chown -R app:app /home/app/admin/tmp

USER app
ENV HOME /home/app
WORKDIR /home/app/admin
ENV RAILS_ENV=production
CMD ["bundle", "exec", "iodine", "-port", "8080"]