Simple Dockerfile using npm

Dockerfile

FROM node:12.5.0-stretch-slim

# Install tini, per best-practices. See:
# https://github.com/nodejs/docker-node/blob/master/docs/BestPractices.md#handling-kernel-signals
ARG TINI_VERSION=v0.18.0
ADD https://github.com/krallin/tini/releases/download/${TINI_VERSION}/tini /tini
RUN chmod +x /tini
ENTRYPOINT ["/tini", "--"]

WORKDIR /app

# Install dependencies.
COPY package.json package-lock.json ./
RUN npm ci
# Install application.
COPY src src

CMD ["node", "src/app.js"]