What are the mistakes that crawler agents are prone to make?
This article mainly introduces the mistakes that the reptile agent is easy to make. It is very detailed and has a certain reference value. Friends who are interested must finish reading it.
In general, the following error status code occurs during the use of the agent:
1 、 407ProxyAuthenticationRequired .
The agent authentication information is wrong, user authentication is required, and the correct user authentication header is required.
2 、 429TooManyRequests .
There are two possibilities for returning such a status code: 1. The requirement is too fast and needs to be reduced; 2. The target website has an anti-crawling mechanism, which limits the requirements of the crawler.
3. The 403 server rejects the request.
It may be caused by the protection measures of the target website. It is recommended to upgrade the crawler strategy or replace the high-quality dragon agent IP.
4 、 504ProxyGatewayTimeoutLink
There are two cases of returning 504: 1. The agent is switching IP, take a break and try again; 2. The target site cannot be achieved.
If a small amount of 504 is normal, and if a large number of 504 is normal, it is recommended to first check whether the target website can not use an agent. If you can access it, it may be due to the protection measures of the target website, and you need to upgrade the crawler policy.
Automatic data acquisition has become a routine operation of Internet practitioners. If crawlers want long-term stable data collection, they will use crawler agents to avoid intellectual property access restrictions on the target site. In the process of data acquisition, a variety of problems will inevitably be encountered. What should we do if we want to quickly analyze the problems in the process of data collection? You can actually tell by the various status codes returned by the proxy HTTP request.
The above is all the contents of this article entitled "what are the mistakes that crawler agents are prone to make?" Thank you for reading! Hope to share the content to help you, more related knowledge, welcome to follow the industry information channel!
