# Builds the required node packages.
FROM node:25 AS builder

WORKDIR /app

COPY src/package*.json ./

RUN npm install

FROM node:25 AS production

WORKDIR /app

COPY package*.json ./

COPY src/* ./

# Sets users and permissions.
RUN groupadd --system --gid 1001 sysmailer && \
    useradd --uid 1001 --gid 1001 -M -N --system sysmailer

COPY --from=builder --chown=sysmailer:sysmailer /app /app

# De-escelates permissions for improved security.
USER sysmailer

# Defines the expected outputs.
EXPOSE 6868

HEALTHCHECK --interval=30s --timeout=3s --start-period=5s --retries=3 \
  CMD node -e "require('http').get('http://localhost:8080', (res) => { process.exit(res.statusCode === 200 ? 0 : 1) })"

CMD ["npm", "start"]