Python异常处理如何应对网络请求问题

• requests.exceptions.ConnectionError：网络连接失败，如主机不可达、DNS 解析失败等。
• requests.exceptions.Timeout：请求超时，服务器未在指定时间内响应。
• requests.exceptions.HTTPError：HTTP 状态码表示错误（如 404、500），可通过 response.raise_for_status() 触发。
• requests.exceptions.RequestException：所有 requests 异常的基类，可用于兜底捕获。

import requests
from requests.exceptions import ConnectionError, Timeout, HTTPError, RequestException
url = "https://httpbin.org/get"
try:
response = requests.get(url, timeout=5)
response.raise_for_status()  # 检查 HTTP 状态码
print("请求成功:", response.json())
except ConnectionError:
print("网络连接失败，请检查网络或目标地址是否可达。")
except Timeout:
print("请求超时，请尝试增加超时时间或重试。")
except HTTPError as e:
print(f"HTTP 错误: {e}")
except RequestException as e:
print(f"请求发生未知错误: {e}")

from tenacity import retry, stop_after_attempt, wait_fixed
@retry(stop=stop_after_attempt(3), wait=wait_fixed(2))
def fetch_data():
try:
response = requests.get("https://api.example.com/data", timeout=5)
response.raise_for_status()
return response.json()
except ConnectionError:
print("连接失败，准备重试...")
raise  # 触发重试
except Timeout:
print("请求超时，准备重试...")
raise

import logging
logging.basicConfig(level=logging.INFO)
logger = logging.getLogger(name)
try:
response = requests.get("https://example.com", timeout=3)
response.raise_for_status()
except RequestException as e:
logger.error(f"请求失败: {e}, URL: {url}")
print("数据加载失败，请稍后重试。")