Almost every computer comes shipped with powerful tools that web developers, market researchers, and many others can use to transfer data through network protocols.
A cURL is a command-line tool that enables a wide variety of use cases ranging from testing API output to seeing whether the destination website is down or sending data. For example, if you use cURL with a proxy, you can use it for web scraping.
What is cURL
Client URL is the tool you can use with your command line, and most developers use it to send and receive data from the server. An omnipresent tool supports different protocols, including HTTP, HTTPS, and FTP.
The basic command for cURL users fetches data from the destination server, and it goes like this.
You should follow the basic command with the URL of the website. In this case, you can retrieve the HTML source for this website.
Aside from being an extremely popular and powerful tool, cURL is more than that. The project also includes the libcurl development library, which can help to broaden the use cases.
Using cURL to send API requests
If you’re trying to test if the API is working correctly, you can use cURL. However, the requests you have to send have several parts. First, an endpoint is an address where you send the request.
Next, you must select the appropriate HTTP method to send the package. You can use GET, POST, PUT or DELETE.
If you want to get data from the server, you should use GET. POST sends information to the server. Testing API with POST requires you to send JSON arguments.
Curl –data “name=John&surname=Doe” http://sampleserver.com
You can also create or update resources like a record in the database if you use PUT for API requests.
As its name suggests, DELETE will delete the resource on the destination.
Headers are the third part of the API request, and it comes with metadata, while the Body has the data you want to send.
Other use cases for cURL
One of the most common cURL uses outside of development is for web scraping. However, you will have to use additional resources to work effectively on scrapping projects. Proxy servers can help immensely in this task. So, if you need web scraping for market research, product pricing comparison, lead generation, big data, or others, you can resort to cURL with proxy.
If you try web scraping from your IP address, the destination server might notice suspicious behavior and block your IP. Proxy servers come in handy for these projects because they act as a middleman. Professional proxies will hide your IP address and work as though your browsing website is from the same country. Proxies can also alternate IP addresses so that the server won’t suspect you are doing anything out of the ordinary.
Because proxies change your IP address, you can also use it to avoid geo-location restrictions. Proxies add a layer of security for your cURL use cases. While the Client URL tool uses internet protocols to interact with the destination server and websites, proxy servers can make those requests anonymous.
You will, however, need to set up and configure cURL to use it with a proxy. If you want to connect with a proxy server, you will have to know the address, port, and protocol. Because it is not recommended to use free proxies as they might create more harm than help, you should go with paid pro solutions. That will also add a username and password for authentication when you start using the proxy with cURL.
HTTP and HTTPS are the two most used protocols, and the command line for both cases looks the same.
Professional market researchers and web scrapers can always automate cURL using proxy servers. There are a couple of ways to do it. You can configure cURL by creating an alias
$ alias curl=’’curl -x http://sampleserver.com”
You will have to reload the shell, and cURL will use an alias and proxy
$ curl https://sampleserver.com
Another way to automate cURL with proxy is by using .curlrc. For example, if you add the command line to -/.curlrc, you can make it go through the proxy.
proxy=http://sampleserver.com
Environment variables are another way to make cURL using proxy as a default option.
$ export http_proxy=http://sampleserver.com
Conclusion
a cURL is an incredible tool available on all platforms natively or through an easy installation. You can use the command line solution to send and receive data through internet protocols like HTTP, HTTPS, FTP, and many others. Communication and interaction with API, servers, and websites are seamless with cURL. You can combine it with tools like proxy servers for added security and difficult tasks like web scraping. cURL with proxies will go behind geo-location restrictions and enable data retrieval.