python 关于函数递归调用自己

时间:2021-07-16 10:36:42

爬取b站博人传

每页短评20个,页数超过1000页,

代码如下

import requests
import json
import csv
def main(start_url):
headers = {'User-Agent': 'Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/73.0.3683.75 Safari/537.36',}
res = requests.get(url=start_url,headers=headers).content.decode()
data = json.loads(res)
try:
data = data['result']['list']
except:
print('-----------')
cursor = re.findall('"cursor":"(\d+)",',res) for i in data:
mid = i['author']['mid']
uname = i['author']['uname']
content = i['content']
content= content.strip()
try:
last_index_show = i['user_season']['last_index_show']
except:
last_index_show = None print(mid,uname,content,last_index_show)
print('------------------------') with open('borenzhuan_duanping.csv', 'a', newline='',encoding='utf-8')as f:
writer = csv.writer(f)
writer.writerow([mid,uname,content,last_index_show]) if cursor:
next_url = 'https://bangumi.bilibili.com/review/web_api/short/list?media_id={}&folded=0&page_size=20&sort=0&sort=0&cursor='.format(id) + cursor[0]
main(next_url)
else:
print('抓取完成') if __name__ == '__main__': zhuye_url = 'https://www.bilibili.com/bangumi/media/md5978/'
id = re.findall('md(\d+)', zhuye_url)[0]
start_url = 'https://bangumi.bilibili.com/review/web_api/short/list?media_id={}&folded=0&page_size=20&sort=0&cursor='.format(id) main(start_url)

在爬取过程中发现,每当递归到999会发生异常

RecursionError: maximum recursion depth exceeded in comparison

这个函数在递归自身是发生的异常

只需要在程序开头添加

import sys
sys.setrecursionlimit(100000)

防止内存爆炸