Web Page Parsing Libraries|Recommendations for Efficient Web Page Parsing Libraries in Python

First, why the web page resolution is always blocked IP, you may have missed this step.

Friends engaged in web parsing should have encountered such a situation: the code is clearly written smoothly, but running suddenly by the target site to block the IP. At this time, don't be in a hurry to doubt life, most likely your request characteristics are recognized. Some websites are like the security door of the supermarket, see the same customer half an hour in and out of twenty times, do not alarm only strange.

Here's a trick for you--Different "vests" for each request.. Just like the agent to perform the task to change clothes, our crawler also need to change IP address often. This time you need a reliable proxy IP service provider, such as the industry's good reputation ipipgo, his family specializes in dynamic residential agent, IP pool has tens of millions of real residential IP, each request can change a new identity.

Second, four Python parsing library real-world evaluation

Choosing the right tools can double efficiency, and I've personally tossed around the following libraries:

HighlightslxmlThis library, parsing speed is comparable to hanging. However, be careful, with xpath positioning elements, remember to check the structure of the page has not changed, this library on the format requirements are more stringent.

Third, the correct way to open the proxy IP

Taking ipipgo's service as an example, adding proxies to the code is actually massively simple. The key is to do a good job of exception handling, after all, the network environment is very complex:

import requests
from lxml import html

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('destination URL', proxies=proxies, timeout=15)
    tree = html.fromstring(response.content)
     Write your parsing logic here...
except requests.exceptions.ProxyError: print("The request is being parsed.
    ProxyError: print("Proxy connection exception. Suggest switching IPs automatically.")

Note that the username and password changed to their own authentication information obtained in the background of ipipgo, his family support pay-per-use mode, with how much count, especially suitable for small and medium-sized projects.

Fourth, avoiding the pit guide: five common mistakes made by novices

1. Die for an IPI've seen people keep retrying even after their IPs are blocked, and as a result, they are permanently blacklisted. The right way to do it is to switch proxies immediately after triggering the ban.

2. Forgetting to set a timeout: Some sites are slow to respond, and not setting a timeout will jam the whole program!

3. User-Agent is too fake: don't use the UA that comes with the requests, go to the web and find a list of real browser UA's

4. Ignore SSL Authentication: Although adding verify=False can skip certificate validation, it increases the risk of being compromised.

5. No request interval: Even with proxies, the frequency should be controlled, too intensive requests will be recognized as DDoS attacks

V. QA Time: You Ask, I Answer

Q: Do free proxies work?
A: Short-term testing can be fun, but formal projects are recommended to use a paid service like ipipgo. The biggest problem with free proxies is that they have low availability, often encounter situations where they can't connect, are slow, and may have security risks.

Q: Do I have to change my IP for each request?
A: Depends on the strength of the wind control of the target website. Ordinary information sites may not be needed, but e-commerce and social networking sites are recommended to change every time. ipipgo's API supports automatic IP replacement by number of requests, which is especially suitable for high-frequency collection scenarios.

Q: What should I do if I encounter dynamically loaded data?
A: You can use it with Selenium or Playwright, and remember to configure the proxy for the browser driver as well. Here's a tip: use ipipgo's mobile IP to better simulate the mobile browser environment.

Finally, web parsing is not about who can write 6 codes, but whose strategy is closer to the real operation. Use a good proxy IP this "invisibility cloak", coupled with a reliable parsing library, in this era of big data can steadily dig into the gold mine. Technical problems are welcome to ipipgo developer community exchanges, their technical customer service response speed thief, more reliable than some of the big manufacturers.