# A debian-base image is used for cloning the repository and installing the
# dependencies.
FROM node:dubnium AS build

WORKDIR /var/node

ARG TAG
ARG SSH_PRIVATE_KEY

# 1) An SSH key is needed to clone the repoository, and github needs to be a
# known host so that ssh doesn't prompt for key verification.

# 2) The repo is cloned, then the TAG is checked out.

# 3) Install the dependencies and build.

# 4) Remove dev dependencies and install prod.
RUN mkdir /root/.ssh/ \
  && echo "${SSH_PRIVATE_KEY}" > /root/.ssh/id_rsa \
  && chmod 600 /root/.ssh/id_rsa \
  && touch /root/.ssh/known_hosts \
  && ssh-keyscan github.com >> /root/.ssh/known_hosts \
  && git clone git@github.com:<MY_PRIVATE_REPO_HERE>.git . \
  && git checkout ${TAG} \
  && npm install \
  && npm run build \
  && rm -rf node_modules \
  && npm install --only=production

# An alpine image is used for the resulting image.  It has the built
# application and dependencies needed to run it, but not much else.  It does
# not contain the SSH key in the image's history.
FROM node:dubnium-alpine

WORKDIR /var/node

# Copy the production assets.
COPY --from=build ["/var/node/package.json", "./package.json"]
COPY --from=build ["/var/node/connections.json", "./connections.json"]
COPY --from=build ["/var/node/dist/", "./"]
COPY --from=build ["/var/node/node_modules", "./node_modules"]

RUN npm install -g forever

# The application runs under the node user.
USER node
EXPOSE 3000

ENTRYPOINT ["forever", "--minUptime", "1000", "--spinSleepTime", "1000"]
CMD ["main.js"]