Dockerfile

# Multi-stage build optimized for Render free tier

# Stage 1: Build React frontend
FROM node:18-alpine AS frontend-build
WORKDIR /app/frontend

# Copy package files
COPY frontend/package*.json ./
RUN npm ci --only=production

# Copy frontend source and build
COPY frontend/ ./
RUN npm run build

# Stage 2: Python backend with built frontend
FROM python:3.11-slim

# Set working directory
WORKDIR /app

# Install system dependencies (minimal for free tier)
RUN apt-get update && apt-get install -y \
    curl \
    && rm -rf /var/lib/apt/lists/* \
    && apt-get clean

# Copy backend requirements and install Python dependencies
COPY backend/requirements.txt ./
RUN pip install --no-cache-dir -r requirements.txt

# Copy backend source
COPY backend/ ./

# Copy built frontend from previous stage
COPY --from=frontend-build /app/frontend/build ./frontend/build

# Render uses PORT environment variable
ENV ENVIRONMENT=production

# Health check for Render
HEALTHCHECK --interval=30s --timeout=10s --start-period=30s --retries=3 \
    CMD curl -f http://localhost:${PORT:-8000}/health || exit 1

# Use PORT from environment (Render requirement)
CMD ["sh", "-c", "python main.py"]