# 多阶段构建 - 第一阶段：依赖安装
FROM python:3.10-slim as builder

WORKDIR /build

# 安装系统依赖（某些Python包需要编译）
RUN apt-get update && apt-get install -y --no-install-recommends \
    gcc \
    && rm -rf /var/lib/apt/lists/*

# 复制requirements并安装Python依赖
COPY requirements.txt .
RUN pip install --user --no-cache-dir -r requirements.txt

# 第二阶段：运行时镜像
FROM python:3.10-slim

WORKDIR /app

# 创建非root用户（安全最佳实践）
RUN useradd -m -u 1000 appuser

# 从builder阶段复制已安装的依赖
COPY --from=builder /root/.local /home/appuser/.local

# 复制应用代码
COPY --chown=appuser:appuser . .

# 设置环境变量
ENV PATH=/home/appuser/.local/bin:$PATH \
    PYTHONUNBUFFERED=1 \
    PYTHONDONTWRITEBYTECODE=1

# 切换到非root用户
USER appuser

# 暴露端口
EXPOSE 8000

# 健康检查
HEALTHCHECK --interval=30s --timeout=10s --start-period=5s --retries=3 \
    CMD python -c "import urllib.request; urllib.request.urlopen('http://localhost:8000/docs')" || exit 1

# 启动应用
CMD ["uvicorn", "main:app", "--host", "0.0.0.0", "--port", "8000", "--workers", "2"]