How to set proxy for cURL in Ubuntu?

cURL is a powerful command-line tool used for transferring data with URLs. It supports various protocols and can be configured to use a proxy server for its requests. In this guide, we’ll show you how to set up cURL to use a proxy in Ubuntu.

Step 1: Identify Your Proxy Server

Before configuring cURL, you need to know your proxy server’s details, including the IP address and port number. The common format for a proxy server is:

http://username:[email protected]:port

If your proxy does not require authentication, you can simply use:

http://proxyserver.com:port

Step 2: Using cURL with Proxy

You can specify the proxy directly in the cURL command using the -x or --proxy option. Here’s how to do it:

For HTTP Proxy

If your proxy server uses HTTP, you can run the following command:

curl -x http://proxyserver.com:port http://example.com

For HTTPS Proxy

If you need to use an HTTPS proxy, the command is similar:

curl -x https://proxyserver.com:port https://example.com

With Authentication

If your proxy requires authentication, include your username and password in the command:

curl -x http://username:[email protected]:port http://example.com

Example Command

Here’s a complete example of using cURL with a proxy:

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

Or, with authentication:

curl -x http://user:[email protected]:8080 http://example.com

Step 3: Setting Environment Variables (Optional)

If you frequently use a proxy with cURL, you might want to set environment variables to avoid specifying the proxy each time. You can do this by adding the following lines to your ~/.bashrc or ~/.bash_profile file:

export http_proxy="http://proxyserver.com:port"
export https_proxy="http://proxyserver.com:port"

If your proxy requires authentication:

export http_proxy="http://username:[email protected]:port"
export https_proxy="http://username:[email protected]:port"

After adding these lines, run the following command to apply the changes:

source ~/.bashrc

Now you can use cURL without specifying the proxy each time:

curl http://example.com

Step 4: Testing Your Configuration

To verify that cURL is using the proxy, you can make a request to an external service that returns your IP address. For example:

curl -x http://proxyserver.com:port http://httpbin.org/ip