在Python爬蟲庫中處理異常情況非常重要,以確保爬蟲在遇到問題時能夠正常運行。以下是一些建議和方法來處理異常:
try:
# 可能引發異常的代碼
response = requests.get(url)
response.raise_for_status()
except requests.exceptions.RequestException as e:
# 處理異常
print(f"請求錯誤: {e}")
Exception
類,以便更準確地處理不同類型的錯誤。例如:try:
# 可能引發異常的代碼
response = requests.get(url)
response.raise_for_status()
except requests.exceptions.HTTPError as e:
# 處理HTTP錯誤
print(f"HTTP錯誤: {e}")
except requests.exceptions.Timeout as e:
# 處理超時錯誤
print(f"超時錯誤: {e}")
except requests.exceptions.RequestException as e:
# 處理其他請求異常
print(f"請求錯誤: {e}")
logging
模塊記錄異常信息,以便在出現問題時進行調試和分析。例如:import logging
logging.basicConfig(filename="spider.log", level=logging.ERROR)
try:
# 可能引發異常的代碼
response = requests.get(url)
response.raise_for_status()
except requests.exceptions.RequestException as e:
# 處理異常并記錄日志
logging.error(f"請求錯誤: {e}")
import time
max_retries = 3
retry_count = 0
while retry_count < max_retries:
try:
# 可能引發異常的代碼
response = requests.get(url)
response.raise_for_status()
break # 請求成功,跳出循環
except requests.exceptions.RequestException as e:
# 處理異常并記錄日志
logging.error(f"請求錯誤: {e}")
retry_count += 1
time.sleep(2) # 等待2秒后重試
else:
# 請求失敗,執行其他操作
print("請求失敗,已達到最大重試次數")
通過這些方法,您可以更有效地處理Python爬蟲庫中的異常情況,確保爬蟲在遇到問題時能夠正常運行。