Dockerfile

FROM alpine:3

USER root

ENV HOME /home
ENV APP_DIR $HOME/docker/app

# http://pkg-shadow.alioth.debian.org/features.php
ENV TEMPORARY_DEPENDENCIES='shadow'
RUN apk --no-cache add bash ${TEMPORARY_DEPENDENCIES}

# add user as per: https://docs.docker.com/engine/userguide/eng-image/dockerfile_best-practices/#user
RUN groupadd -r docker && useradd --no-log-init -r -g docker docker
RUN chown -R docker $HOME

RUN apk --no-cache add \
    nodejs-current \
    nodejs-current-npm \
    # clean up obsolete files
    && rm -rf /tmp/* /root/.npm

# clean no longer needed dependencies
RUN apk del ${TEMPORARY_DEPENDENCIES}

# create directories
RUN mkdir -p $APP_DIR
RUN mkdir -p $APP_DIR/tests_output/screenshots
RUN chown -R docker $APP_DIR

WORKDIR $APP_DIR

COPY --chown=docker:docker package.json package-lock.json ./

# switch to docker user to ensure correct permissions for npm dependencies
USER docker

# `npm ci` actually enforces the package-lock and is way faster!
# See https://docs.npmjs.com/cli/ci.html
RUN npm ci --ignore-scripts --unsafe-perm --loglevel warn --no-progress || \
    npm install --ignore-scripts --unsafe-perm --loglevel warn --no-progress

USER root

# add rest of repo to image (doing this after installing npm dependencies
# makes for a faster development workflow because only a change to package*.json
# will force docker to rebuild the "npm install" layer above)
COPY --chown=docker:docker . ./

ENV NODE_ENV=test
ENV TESTS_DIRECTORY=tests
ENV PATH="${PATH}:${APP_DIR}/node_modules/nightwatch/bin"

USER docker