Dockerfile

# Multi-stage build for Flask application
# Stage 1: Builder
FROM python:3.11-slim AS builder

# Install build dependencies
RUN apt-get update && apt-get install -y \
    gcc \
    g++ \
    libmariadb-dev \
    pkg-config \
    && rm -rf /var/lib/apt/lists/*

# Create virtual environment
RUN python -m venv /opt/venv
ENV PATH="/opt/venv/bin:$PATH"

# Copy and install requirements
COPY requirements.txt .
RUN pip install --no-cache-dir --upgrade pip && \
    pip install --no-cache-dir -r requirements.txt && \
    pip install --no-cache-dir gunicorn gevent

# Stage 2: Runtime
FROM python:3.11-slim

# Install runtime dependencies
RUN apt-get update && apt-get install -y \
    libmariadb3 \
    curl \
    && rm -rf /var/lib/apt/lists/* && \
    apt-get clean

# Create non-root user
RUN groupadd -r flask && useradd -r -g flask flask

# Set working directory
WORKDIR /app

# Copy virtual environment from builder
COPY --from=builder /opt/venv /opt/venv
ENV PATH="/opt/venv/bin:$PATH"

# Copy application code
COPY --chown=flask:flask . .

# Create necessary directories
RUN mkdir -p /app/logs /app/data && \
    chown -R flask:flask /app

# Switch to non-root user
USER flask

# Environment variables
ENV PYTHONUNBUFFERED=1
ENV PYTHONDONTWRITEBYTECODE=1
ENV FLASK_APP=app.py

EXPOSE 5000

# Health check
HEALTHCHECK --interval=30s --timeout=10s --start-period=40s --retries=3 \
    CMD curl -f http://localhost:5000/health || exit 1

# Use gunicorn for production
CMD ["gunicorn", "-w", "4", "-b", "0.0.0.0:5000", "-k", "gevent", "--timeout", "120", "--access-logfile", "-", "--error-logfile", "-", "app:app"]