Dockerfile

FROM node:18-alpine AS base

# Install dependencies only when needed
FROM base AS deps
RUN apk add --no-cache libc6-compat
RUN corepack enable && corepack prepare pnpm@latest --activate

WORKDIR /app

# Copy the entire project first to ensure config files are available
COPY . .

# Install dependencies based on the preferred package manager
RUN pnpm install --frozen-lockfile

# Rebuild the source code only when needed
FROM deps AS builder

WORKDIR /app

# Copy source code
COPY . .

# Ensure next.config.js has output: 'standalone' configuration
RUN grep -q "output: 'standalone'" next.config.js || echo "Standalone output config is missing in next.config.js"

# Build the application
RUN pnpm build

# Verify the standalone output was created
RUN ls -la .next/ && \
    if [ ! -d ".next/standalone" ]; then \
      echo "ERROR: .next/standalone directory was not created by the build"; \
      echo "Make sure next.config.js has output: 'standalone' configuration"; \
      exit 1; \
    fi

# Production image, copy all the files and run next
FROM base AS runner
WORKDIR /app

RUN addgroup --system --gid 1001 nodejs && \
    adduser --system --uid 1001 nextjs && \
    mkdir .next && \
    chown nextjs:nodejs .next

COPY --from=builder /app/public ./public
COPY --from=builder --chown=nextjs:nodejs /app/.next/standalone ./
COPY --from=builder --chown=nextjs:nodejs /app/.next/static ./.next/static

USER nextjs

EXPOSE 3000

ENV NODE_ENV production

ENV PORT 3000
ENV HOSTNAME "0.0.0.0"

# server.js is created by next build from the standalone output
CMD ["node", "server.js"]