Python Web Crawling Methods: A Comparative Analysis of 8 Techniques

First, hand to teach you to match a basic crawler

The most common question asked by newcomers to web crawling:Why do I need a proxy IP?For example, if you visit a website 30 times in a row with your own IP, you will be speed-limited or blocked. At this time you need a proxy service like ipipgo, each request for a different "armor", so that the site thinks it is a different user in the visit.

import requests
from itertools import cycle

ip pool = ['114.114.114.1:8080','121.121.121.2:8888'] here replace with the real IP provided by ipipgo
proxy cycler = cycle(ip pool)

for _ in range(5).
    Current proxy = next(proxy cycler)
    try.
        resp = requests.get('https://目标网站.com',
                          proxies={'http':current proxy},
                          timeout=5)
        print(resp.text[:100])
    except Exception as e.
        print(f "Rollover with {current proxy}:",e)

Second, the eight ways to capture the actual combat comparison

Here's a real-world comparison table, straight to the dry end:

Third, the Scrapy framework depth tuning

Using Scrapy with ipipgo's proxy is a match made in heaven! Add a middleware to middlewares.py:

class IpipgoProxyMiddleware.
    def process_request(self, request, spider).
        request.meta['proxy'] = 'http://用户名:密码@gateway.ipipgo.com:端口'
         Check the ipipgo backend for specific parameters

Remember to turn on this middleware in settings, and it is recommended that theRetesting mechanismrespond in singingAgent RotationUsed in combination, the success rate can go up to 98% or more.

Fourth, to avoid the anti-climbing tawdry operation

Some sites will detect the User-Agent in the request header, this time not only to change the IP, but also with ipipgo'sTerminal Fingerprint EmulationFunction. Disguise the request header like this:

headers = {
    'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36',
    
    'Referer': 'https://www.google.com/'
}

V. Practical QA First Aid Kit

Q: What should I do if my proxy IP is not working?
A: choose ipipgo's dynamic pool service, their IP survival time control in 5-15 minutes automatically replaced, the background can also be set to automatically eliminate the failure of the node

Q: What should I do if I encounter Cloudflare protection?
A: on ipipgo'sResidential AgentsPackage, with the request rate control of 2 seconds / time, pro-tested effective

Q: What package should I choose for a large amount of data?
A: Reptile veterans use ipipgo'sEnterprise Dynamic TunnelingIt supports automatic IP switching every second, so you don't have to manage your own IP pool.

Six, upgraded version of the skills release

When you encounter a particularly difficult website, try this trick: put ipipgo'sStatic Residential IPMix it up with regular data center IPs. Slowly pick up important data with residential IPs, and wildly spike regular content with data center IPs for cost savings and insurance.

 Hybrid Proxy Policy Example
Advanced IP Pool = [
    'residential.ipipgo.com:30001', residential IP
    'dc01.ipipgo.com:30002', Data Center IP
    'dc02.ipipgo.com:30002'
]

A final reminder for newbies:Don't be greedy!Control the frequency of requests and use the QPS monitoring dashboard provided by ipipgo to fine tune your data.