Dockerfile

# syntax=docker/dockerfile:1

ARG NODE_VERSION=20.18.0

FROM node:${NODE_VERSION}-alpine

# Use production node environment by default.
ENV NODE_ENV production

WORKDIR /usr/src/app

# IMPORTANT : Requires to have already generated the package-lock.json file with `npm install --omit=dev`.
# Download dependencies as a separate step to take advantage of Docker's caching.
# Leverage a cache mount to /root/.npm to speed up subsequent builds.
# Leverage a bind mounts to package.json and package-lock.json to avoid having to copy them into
# into this layer.
RUN --mount=type=bind,source=package.json,target=package.json \
    --mount=type=bind,source=package-lock.json,target=package-lock.json \
    --mount=type=cache,target=/root/.npm \
    npm ci --omit=dev

# Copy the rest of the source files into the image.
COPY . .

# Install dependencies if not found, which shouldn't happen.
RUN if [ ! -d "node_modules" ]; then npm install --omit=dev --no-audit --no-package-lock-only --no-update-notifier --no-fund; fi

# Expose the port that the application listens on.
EXPOSE 3000

# Run the application.
CMD npm start