Dockerfile

FROM node:18-alpine AS base

# install dependencies
FROM base AS deps
RUN apk add --no-cache libc6-compat
WORKDIR /app
COPY package*.json ./
RUN npm ci

# rebuild when needed
FROM base AS builder
WORKDIR /app
COPY --from=deps /app/node_modules ./node_modules
COPY . .
ENV BUILD_STANDALONE true
RUN npm run build

# production image
FROM base AS runner
WORKDIR /app
ENV NODE_ENV production

RUN addgroup --system --gid 1001 nodejs
RUN adduser --system --uid 1001 nextjs
COPY --from=builder /app/public ./public

# set the correct permission
RUN mkdir .next
RUN chown nextjs:nodejs .next

# reduce image size
COPY --from=builder --chown=nextjs:nodejs /app/.next/standalone ./
COPY --from=builder --chown=nextjs:nodejs /app/.next/static ./.next/static

# non-root user
USER nextjs

EXPOSE 3000
ENV PORT 3000

CMD ["node", "server.js"]