Python Web Crawler: Proxy IP to solve anti-climbing problem

First, why does the site always block your crawler?

Crawlers of friends know that many sites are like a radar, caught crawlers on the IP block, this thing is not actually the blame of the webmasters, they are also malicious crawlers to get scared. Imagine, if someone with the same IP address to visit your site 100 times per second, who have to be anxious.

This is where proxy IPs come in handy. As if you go to participate in the Comic Con, each time you change different cosplay costumes, the security guards will not recognize the same person. Proxy IP is to give the crawler constantly change "armor", so that the site is mistakenly thought to be different users visit.

Second, hand to teach you to use Python + proxy IP

Here's a real-world example, practicing with the Douban movie list. Let's first look at how ordinary crawlers get blocked:

import requests

url = 'https://movie.douban.com/top250'
response = requests.get(url)
print(response.status_code) probability of returning 418

This is the time to offer up a proxy IP. Take the services of ipipgo for example, they offerDynamic Residential Agents, especially suitable for such scenarios that require frequent IP changes.

proxies = {
    'http': 'http://用户名:密码@gateway.ipipgo.com:端口',
    'https': 'https://用户名:密码@gateway.ipipgo.com:端口'
}

try.
    response = requests.get(url, proxies=proxies, timeout=10)
    print(response.status_code) You should see 200 this time.
except Exception as e.
    print("Request Exception:", str(e))

Third, the three major guide to avoiding the pitfalls of choosing a proxy IP

With a mixed bag of agency services on the market, keep these three key points in mind:

Special mention to ipipgo'sIntelligent RotationThe ability to automatically change IPs based on the frequency of visits is a lifesaver for crawler tasks that need to run for long periods of time.

IV. Practical Frequently Asked Questions QA

Q: What should I do if my proxy IP is not working?
A: This is most likely that the IP has been pulled by the target site, it is recommended to use a service provider like ipipgo that provides real-time IP replacement, their IP pool is updated with millions of addresses every day.

Q: How can I tell if a crawler has been recognized?
A: Pay attention to these three signals: 1. frequent CAPTCHA 2. abnormal return status code 3. suddenly less data obtained. It is time to check if the proxy IP is exposed.

Q: Which is better, dynamic or static proxies?
A: Depends on the usage scenario. Dynamic proxies are suitable for high-frequency access (e.g., ticket scripts), and static proxies are suitable for scenarios that require fixed IPs (e.g., API interfacing). ipipgo provides both types, and you can switch between them at any time.

V. Upgrade your reptile survival skills

It's not enough to have a proxy IP, you have to learn the combination:
1. Randomly set the User-Agent in the request header
2. Control the frequency of visits (don't be greedy)
3. Working with the Cookies Pool
4. Local caching of important data

To cite a real case: an e-commerce price monitoring project, with ipipgo's proxy service + random delay (1-3 seconds), running continuously for 30 days without being blocked, the data collection success rate remains above 98%.

A final reminder for newbies:Don't use an unknown agent on the cheap.Some bad agents will steal your data or divert your crawler requests to do bad things. Professional things to professional people, like ipipgo this kind of formal qualification, provide API documentation and technical support, use only solid.