Python爬虫求助:如何解决常见问题与优化代码?
如何在 企查查 网站自动爬取多家公司或企业的相关数据 ?
Python爬虫求助:如何解决常见问题与优化代码?
1 回复
帖子回复:
哥们儿,爬虫这玩意儿确实容易踩坑。我直接给你几个最常见问题的代码级解决方案和优化思路,你对着改就行。
1. 反爬:User-Agent被识别
直接上完整代码,用fake-useragent动态轮换:
from fake_useragent import UserAgent
import requests
ua = UserAgent()
headers = {'User-Agent': ua.random}
response = requests.get('https://example.com', headers=headers)
2. IP被封:加代理池
import requests
proxies = {
'http': 'http://your-proxy-ip:port',
'https': 'https://your-proxy-ip:port'
}
response = requests.get('https://example.com', proxies=proxies, timeout=5)
3. 解析优化:用lxml替代正则
from lxml import etree
import requests
html = requests.get('https://example.com').text
tree = etree.HTML(html)
# 比正则稳定多了
titles = tree.xpath('//h2[@class="title"]/text()')
4. 异步提速(aiohttp示例)
import aiohttp
import asyncio
async def fetch(session, url):
async with session.get(url) as response:
return await response.text()
async def main():
async with aiohttp.ClientSession() as session:
tasks = [fetch(session, f'https://example.com/page/{i}') for i in range(10)]
results = await asyncio.gather(*tasks)
asyncio.run(main())
5. 结构化存储优化
import pandas as pd
from sqlalchemy import create_engine
# 数据攒到DataFrame再批量入库
df = pd.DataFrame(data_list)
engine = create_engine('sqlite:///data.db')
df.to_sql('table_name', engine, if_exists='append', index=False) # 比逐条insert快10倍
关键点总结:
- 动态UA和代理解决反爬
- lxml比正则更稳
- 异步IO提升吞吐量
- 批量操作数据库
一句话建议: 爬虫的核心是模拟真人操作,别太频繁,该加延迟就加延迟。
(注:实际部署时记得遵守robots.txt,控制请求频率)

