Web crawlers are programs that automatically browse the Internet and crawl the required data. However, directly using real IP addresses to make a large number of requests is often regarded as an attack by the target website, resulting in the IP being blocked. In order to bypass this restriction, using proxy IPs has become a common solution.

Among many types of proxies, residential proxy IPs are highly favored for their high anonymity and ability to simulate real user behavior. This article will introduce in detail how to use Curl in combination with residential proxy IPs to achieve efficient and secure global data crawling.

What is Curl

Curl is a powerful command line tool for sending and receiving data, supporting multiple protocols, including HTTP, HTTPS, FTP, etc. With Curl, users can easily send requests to the target website and get response data.

Basic usage of Curl

The basic usage of Curl is very simple, just enter curl [options] [URL] in the command line. For example, to get the content of a web page, you can execute curl http://example.com.

Curl also provides a wealth of options for customizing requests. For example, the -H option is used to add additional HTTP header information, the -X option is used to specify the request method (such as GET, POST, etc.), and the -o option is used to save the response to a file.

What is a residential proxy IP?

Residential proxy IP refers to the IP address assigned by real home users. They are usually assigned to home broadband users by ISPs (Internet service providers). Compared with data center proxy IPs, residential proxy IPs have higher anonymity and are more difficult to identify.

Advantages of residential proxy IP

High anonymity: Since residential proxy IPs come from real home users, they are more difficult to be identified as crawlers by target websites.

Simulate real user behavior: Residential proxy IPs can simulate real users' network behavior, such as visiting websites, clicking links, etc., thereby bypassing anti-crawler mechanisms.

Wide geographical distribution: Residential proxy IPs are distributed all over the world, which can meet the data crawling needs of different regions.

Using Curl and residential proxy IP to scrape data

Getting residential proxy IP

First, you need to get the proxy IP address and port number from a reliable residential proxy service provider. These services usually provide an API interface or control panel for users to query and obtain the proxy IP.

Set Curl's proxy parameters

In Curl's command line parameters, the -x or --proxy option is used to set the proxy server. You need to pass the obtained residential proxy IP address and port number as parameters to Curl.

For example, if the proxy IP is 123.45.67.89 and the port number is 8080, you can set Curl's proxy parameters with the following command:

curl -x 123.45.67.89:8080 http://example.com

Send a request and scrape data

After setting the proxy parameters, you can use Curl to send requests and scrape data from the target website. You can set HTTP header information by adding the -H option to simulate real user requests.

For example, to crawl a web page that requires login, you may need to set HTTP header information such as User-Agent and Cookie. Here is an example command:

curl -x 123.45.67.89:8080 -H "User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/58.0.3029.110 Safari/537.3" -H "Cookie: session_id=abc123" http://example.com/login

Notes

Reliability of proxy service provider: Make sure the residential proxy service provider you choose is reliable to avoid data leakage and abuse.

Comply with website terms of use: Before crawling data, be sure to read and comply with the terms of use of the target website to avoid illegal crawling.

IP rotation: In order to avoid being blocked by the target website, it is recommended to change the proxy IP address regularly. You can automate this process by writing a script.

Performance optimization: Since proxy servers may be slower than direct connections, you need to consider how to optimize your crawling strategy to improve crawling efficiency.