How to Crawl Websites with Python: A Tutorial for Beginners

The website crawler is blocked IP?

Recently, several friends asked me what to do if I always get my IP blocked by websites for writing crawlers in Python. I have too much say in this matter! Last year, when doing e-commerce price comparison project, for three consecutive days by a platform blocked more than 20 IP, so angry that I almost smashed the keyboard. Later found that the use of proxy IP is the right solution, and today I will share my practical experience with you.

Why doesn't your crawler survive three episodes?

Many newbies tend to overlookAccess Frequency DetectionThis pit. As a chestnut, your home with broadband IP is fixed, play around with grabbing data like this:

import requests
for i in range(1000):: response = requests.get('')
    response = requests.get('https://目标网站')
     Processing data...

Not out of a incense stick kung fu, absolutely received 403 forbidden. website fire is not vegetarian, the same IP high-frequency access, immediately pull the black is not negotiable.

The right way to open a proxy IP

Here's where the big killers come in--Proxy IP ServiceThe principle is like a game of "face painting", where each request changes its IP address. The principle is like a game of "face changing", where the IP address is changed for each request. RecommendedipipgoThe dynamic proxies, his IP pool is large enough that my current project calls 50,000+ times a day and hasn't rolled over yet.

Python Proxy Configuration in Five Steps

Take ipipgo's API proxy as an example (don't use free proxies! 99% are pits):

import requests

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

 Remember to add a timeout and retry mechanism
try: response = requests.get('destination URL', 'https')
    response = requests.get('destination URL', proxies=proxies, timeout=10)
    print(response.text)
except Exception as e.
    print(f'Request failed: {str(e)}')

Focused Reminder:

1. It is advisable to change the proxy IP before each request (ipipgo supports automatic rotation)
2. Set reasonable latency, don't crash the web server
3. Works better with random User-Agent.

A practical guide to avoiding the pit

I encountered a typical problem when I helped a friend debug a crawler last month: it was obviously using a proxy, but it was still recognized. Later, I realized that it wasCookie leaks real IP. The solution is simple, disable cookies in requests.Session():

session = requests.Session()
session.trust_env = False The key setting!
response = session.get(url, proxies=proxies)

Frequently Asked Questions QA

Q: Do I have to use a paid proxy?
A: Free proxies can be used for short-term testing, but professional services like ipipgo are highly recommended for commercial projects. I tried a free proxy last week, and 8 out of 10 IPs failed, which was a waste of time.

Q: How can I tell if a proxy is in effect?
A: Visit https://www.ipipgo.com/checkip to see if the returned IP address has changed

Q: What should I do if I encounter an SSL certificate error?
A: add verify=False parameter to requests.get(), but it is only recommended to use it for testing purposes

Finally, to do a data crawl to comply with the website robots agreement. Use ipipgo this kind of high stash of proxy also want to control the frequency of request, do a moral crawler engineer ~!