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This article focuses on "how to use proxy ip for distributed crawlers". Interested friends may wish to take a look. The method introduced in this paper is simple, fast and practical. Let's let the editor take you to learn how to use proxy ip for distributed crawlers.

After using a high-quality agent ip, can you not worry about it? It won't be that simple. In fact, it's being followed. Being anti-crawled is not only a problem of agency, but also needs to consider all aspects of things, but also to improve the crawler agent program, effectively allocate resources, improve work efficiency, and complete the crawler quickly and steadily.

1. Each process randomly extracts a set of IP from the interface API, reuses it, and calls API to get it after failure. The general logic is as follows.

Each process returns a random batch of ip returns from the interface and returns to the ip directory to capture data

If the visit is successful, proceed to the next task.

If it fails, extract a batch of IP from the interface and continue to try.

Program disadvantages: every IP has a deadline. If you take down a hundred IP and use the twentieth, maybe most of them won't work. If a HTTP request is established with a connection timeout of 3 seconds and a read timeout of 5 seconds, it may take 3-8 seconds and may be captured hundreds of times in those 3-8 seconds.

2. Each process randomly gets an IP from the interface API to use, and then calls API to get IP after failure. The general logic is as follows.

For each process, randomly extract an ip from the interface and use this ip to browse resources

If the visit is successful, proceed to the next task.

If it fails, randomly get the IP from the interface and continue to try.

Program defects: the behavior of calling API to obtain IP is very frequent, which will bring great pressure to the proxy server, affect the stability of the API interface, and it is difficult to extract. This scheme is also not suitable for continuous and stable operation.

3. First, a large amount of IP is extracted to the local database, and the IP is extracted from the database. The logic is as follows.

Set up a table in the database, write an import script, and the number of API requests per minute (recommended by consulting IP service providers). The number of IP extracted at a time is 200, with an interval of 1 second, that is, 60 requests can be requested as soon as 1 minute, and the IP list can be imported into the database.

Record the import time in the database. IP.Port. Fields such as expiration time. IP availability status.

Write a crawl script to read the available IP from the database, and each process fetches an IP from the database to use.

Perform the crawl, judge the result, deal with the cookie, etc., as soon as the validation code appears or fails, abandon the IP and replace the IP.

This scheme effectively avoids the consumption of proxy server resources, effectively allocates proxy IP, makes it more efficient and stable, and ensures the persistence and stability of crawler work. As we all know, in order to improve the efficiency of crawling data, we need to use the crawler agent ip, if there is no proxy ip, then the crawler business is impossible, so most crawler collection companies need this product.

At this point, I believe you have a deeper understanding of "how to use proxy ip for distributed crawlers". You might as well do it in practice. Here is the website, more related content can enter the relevant channels to inquire, follow us, continue to learn!

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