Dockerfile

# Install dependencies only when needed
FROM node:21.1-alpine AS deps
# Check https://github.com/nodejs/docker-node/tree/b4117f9333da4138b03a546ec926ef50a31506c3#nodealpine to understand why libc6-compat might be needed.
RUN apk add --no-cache libc6-compat
WORKDIR /app
# Install dependencies based on the preferred package manager
COPY package.json yarn.lock* package-lock.json* pnpm-lock.yaml* ./
RUN \
  if [ -f yarn.lock ]; then yarn --frozen-lockfile; \
  elif [ -f package-lock.json ]; then npm ci; \
  elif [ -f pnpm-lock.yaml ]; then yarn global add pnpm && pnpm i; \
  else echo "Lockfile not found." && exit 1; \
  fi

# Rebuild the source code only when needed
FROM node:21.1-alpine AS builder
WORKDIR /app
COPY --from=deps /app/node_modules ./node_modules
COPY . .

# Next.js collects completely anonymous telemetry data about general usage.
# Learn more here: https://nextjs.org/telemetry
# Uncomment the following line in case you want to disable telemetry during the build.
# ENV NEXT_TELEMETRY_DISABLED 1

# Build app
RUN NODE_ENV=production yarn build

# Production image, copy all the files and run next
FROM node:21.1-alpine AS runner
WORKDIR /app

ENV NODE_ENV production
ENV NEXT_TELEMETRY_DISABLED 1

RUN addgroup --system --gid 1001 nodejs
RUN adduser --system --uid 1001 nextjs

# You only need to copy next.config.js if you are NOT using the default configuration
### next.config.js was updated to generate the standalone files >> Next.js can automatically create a standalone folder which copies only the necessary files for a production deployment 
COPY --from=builder /app/next.config.js ./
COPY --from=builder /app/package.json ./package.json

# Automatically leverage output traces to reduce image size 
# https://nextjs.org/docs/advanced-features/output-file-tracing
COPY --from=builder --chown=nextjs:nodejs /app/.next/standalone ./standalone
COPY --from=builder --chown=nextjs:nodejs /app/public ./standalone/public
COPY --from=builder --chown=nextjs:nodejs /app/.next/static ./standalone/.next/static
COPY --from=builder --chown=nextjs:nodejs /app/.next/static ./.next/static

USER nextjs

ENV PORT 3000
EXPOSE 3000
CMD ["node", "./standalone/server.js"]