Python crawler how to automatically switch the proxy IP? full code example

How to make Python crawlers change their vests automatically?

Imagine you are in front of the supermarket shelves to compare prices repeatedly, and suddenly you are invited by the staff out of the door - this is the real picture of the crawler being blocked by the website's IP. Proxy IP is like preparing countless cloaks for your crawlers, and the auto-switching function allows these clothes to be changed regularly, effectively avoiding being detected by the target website.

Three lines of code to access the ipipgo proxy pool

As an example, the proxy service provided by ipipgo, they provideInstantly available API interfaces, it only takes three lines of code to get fresh proxies:

import requests
api_url = "https://api.ipipgo.com/getproxy"
proxy_data = requests.get(api_url).json()

The returned JSON data contains ip, port, protocol type and other information. ipipgo's residential IP library covers more than 240 regions around the world, which is especially suitable for crawling tasks that need to simulate real user scenarios.

Core logic of automatic switching

Three key components are required to achieve automatic switching:

It is recommended that each completed50 requestsor encountered403 status codeThe toggle is triggered when the A full example is shown here:

from itertools import cycle
import random

class ProxyRotator.
    def __init__(self).
        self.proxy_pool = self._fetch_proxies()
        self.valid_proxies = []
        self.current_proxy = None

    def _fetch_proxies(self).
         Fetch the 50 most recent proxies from ipipgo
        params = {'format': 'text', 'count': 50}
        resp = requests.get('https://api.ipipgo.com/proxies', params=params)
        return resp.text.split('')

    def _validate_proxy(self, proxy).
        try.
            test_url = "https://httpbin.org/ip"
            proxies = {'http': proxy, 'https': proxy}
            return requests.get(test_url, proxies=proxies, timeout=5).ok
        except.
            return False

    def get_proxy(self): while len(self.valid_proxy)
        while len(self.valid_proxies) = 50: self.current_proxy = next(cycle_proxy).
            self.current_proxy = next(cycle(self.valid_proxies))
            self.counter = 0
        self.counter +=1
        return self.current_proxy

A guide to avoiding pitfalls in real-life scenarios

In our e-commerce price monitoring project, we achieve stable collection with the following configuration:

1. set up2 seconds.The random request interval of the
2. After each proxy switchReplacement of User-Agent
3. For important target pages useStatic residential IP for ipipgo
4. Automatically switch when encountering CAPTCHABrowser Fingerprinting

Frequently Asked Questions

Q: What should I do if my proxy IP fails frequently?
A: It is recommended to choose something like ipipgo which offersReal-time validity testingservice providers whose IPs are available for more than 6 hours on average.

Q: How do you balance proxy costs and data quality?
A: Adopt hybrid proxy strategy, use residential IP for pages with strong anti-crawl, use data center IP for ordinary pages. ipipgo supportMixed calls on demandDifferent agent types.

Q: Does the automatic switching affect the crawling speed?
A: Reasonable setting of switching threshold can avoid performance loss. Empirical tests show that when the single IP request interval is >1 second, the delay caused by switching proxies is negligible.

By reasonably configuring the proxy pool and switching strategy, together with the high-quality proxy resources provided by such professional service providers as ipipgo, the stability of the crawler and the efficiency of data collection can be significantly improved. It is recommended to use them in key business segmentsLong-lasting static IPThe IP pool is used for general acquisition tasks, which ensures business continuity and controls costs.