Dockerfile

# Chat Agent - AI Service (Node.js)
# Production-ready Docker image for the chat agent backend service

# ============================================
# Builder Stage - Install dependencies and build
# ============================================
FROM node:20-alpine AS builder

WORKDIR /app

# Copy package files
COPY package*.json ./

# Install all dependencies (including devDependencies for build)
RUN npm install

# Copy source code
COPY tsconfig.json ./
COPY src ./src

# Build TypeScript and remove dev dependencies (consolidated for layer optimization)
RUN npm run build && npm prune --omit=dev

# ============================================
# Production Stage - Minimal runtime image
# ============================================
FROM node:20-alpine

WORKDIR /app

# Copy package files
COPY package*.json ./

# Copy production dependencies from builder (avoids QEMU emulation issues)
COPY --from=builder /app/node_modules ./node_modules

# Copy built application from builder
COPY --from=builder /app/dist ./dist

# Set production environment
ENV NODE_ENV=production

# Expose application port
EXPOSE 3002

# Health check
HEALTHCHECK --interval=30s --timeout=10s --retries=3 --start-period=40s \
  CMD wget --quiet --tries=1 --spider http://localhost:3002/health || exit 1

# Run the application
CMD ["node", "dist/index.js"]