Shulou(Shulou.com)06/03 Report--

This article mainly introduces the website crawler tips, the article is very detailed, has a certain reference value, interested friends must read it!

1. User_agent camouflage and rotation.

In different browser versions, user_agent is important header information about the browser type and the browser submitting the Http request. We can provide a different user_agent for each request, thus bypassing the anti-crawler mechanism of the website detection client. For example, you can randomly put many user_agent into a list and randomly select a request to submit access, and you can find sites that offer various user_agent.

2. Using proxy IP and rotation, viewing ip visits is the most commonly used anti-crawling mechanism. At this time, you can replace different ip addresses with crawled content.

If a host or vps provides a public network ip address, consider using a proxy IP to get the web content for you and then return to your computer. According to transparency, agents can be divided into transparent agents, anonymous agents, and highly anonymous agents:

Transparency proxy: the target site knows that you are using an agent and knows your source IP address, which is obviously not in line with our original intention to use the proxy.

Anonymous proxy: the degree of anonymity is low, that is, the website knows that you use the proxy, but does not know your source IP address.

Highly anonymous proxy: this is the safest way, the target site does not know what proxy you use, nor does it know your source IP.

The way to get an agent can be purchased or crawled by yourself, but the crawling IP is very unstable.

3. Set the access interval.

The anti-crawler mechanisms of many websites set the access interval, and if one of the IP exceeds the specified number of times in a short period of time, it will enter a "cooling CD". Therefore, in addition to rotating IP and user_agent, you can also set a longer access interval, such as not capturing when the page sleeps. Because the original crawler will bring the load pressure on the other side's website, so this kind of prevention can not only prevent the other party from being blocked to a certain extent, but also reduce the other party's visit pressure.

The above is all the contents of this article "what are the tips for website crawlers?" Thank you for reading! Hope to share the content to help you, more related knowledge, welcome to follow the industry information channel!

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