Selenium proxy authentication library for .NET

The challenge

Selenium does not support basic proxy authentication out-of-the-box. It is possible to create an extension that handles proxy authentication and add the extension to the browser, but if you wish to run the driver headless, extensions are not loaded. That's why I created this library.

Workaround

The workaround is to create a local proxy server (this simple library uses Titanium-Web-Proxy) and handle the proxy authentication from there.

Instructions

1. Create the local proxy server

var proxyServer = new SeleniumProxyServer();

2. Add a new endpoint

var localPort = proxyServer.AddEndpoint(new ProxyAuth("123.123.123.123", 80, "prox-username1", "proxy-password1"));

3. Use the endpoint's port when initializing the driver

options.AddArgument($"--proxy-server=127.0.0.1:{localPort}");

Example

public void Test()
{  
    // Create a local proxy server
    var proxyServer = new SeleniumProxyServer();

    // Don't await, have multiple drivers at once using the local proxy server
    TestSeleniumProxyServer(proxyServer, new ProxyAuth("123.123.123.123", 80, "prox-username1", "proxy-password1"));
    TestSeleniumProxyServer(proxyServer, new ProxyAuth("11.22.33.44", 80, "prox-username2", "proxy-password2"));
    TestSeleniumProxyServer(proxyServer, new ProxyAuth("111.222.222.111", 80, "prox-username3", "proxy-password3"));

    while (true) { }
}

private async Task TestSeleniumProxyServer(SeleniumProxyServer proxyServer, ProxyAuth auth)
{
    // Add a new local proxy server endpoint
    var localPort = proxyServer.AddEndpoint(auth);

    ChromeOptions options = new ChromeOptions();
    //options1.AddArguments("headless");

    // Configure the driver's proxy server to the local endpoint port
    options.AddArgument($"--proxy-server=127.0.0.1:{localPort}");

    // Optional
    var service = ChromeDriverService.CreateDefaultService();
    service.HideCommandPromptWindow = true;

    // Create the driver
    var driver = new ChromeDriver(service, options);

    // Test if the driver is working correctly
    driver.Navigate().GoToUrl("https://www.myip.com/");
    await Task.Delay(5000);
    driver.Navigate().GoToUrl("https://amibehindaproxy.com/");
    await Task.Delay(5000);

    // Dispose the driver
    driver.Dispose();
}