修改Django REST framework的默认异常处理方法，补充处理数据库异常和Redis异常。
1）新建utils/exceptions.py

import logging

from rest_framework.views import exception_handler as drf_exception_handler
from rest_framework.response import Response
from rest_framework import status

from django.db import DatabaseError
from redis.exceptions import RedisError

# 获取在配置文件中定义的logger，用来记录日志
logger = logging.getLogger('django')

def exception_handler(exc, context):
    """
    自定义异常处理
    :param exc: 异常
    :param context: 抛出异常的上下文
    :return: Response响应对象
    """
    # 调用drf框架原生的异常处理方法
    response = drf_exception_handler(exc, context)

    if response is None:
        # 获取异常视图对象
        view = context['view']
        if isinstance(exc, DatabaseError) or isinstance(exc, RedisError):
            # 数据库异常
            logger.error('[%s] %s' % (view, type(exc)))
            response = Response({'message': '服务器内部错误'}, status=status.HTTP_500_INTERNAL_SERVER_ERROR)

    return response

2）配置文件中添加

REST_FRAMEWORK = {
    # 异常处理
    'EXCEPTION_HANDLER': 'meiduo_mall.utils.exceptions.exception_handler',
}