Unobtanium.Web.Proxy.Events 0.9.1-beta-2

Unobtanium Web Proxy

A lightweight HTTP(S) proxy server written in C# NET8.0.

Report bugs or raise issues here.

Project reboot

This project is a rewrite of the original Titanium-Web-Proxy project. The original project was last updated two years ago, has been archived by the author on July 9th 2023 and has been inactive since then. This project aims to continue the development of the original project and provide a stable and reliable proxy server library for .NET developers.

Announcement Reboot discussion Issues

Reboot focus

• net8.0 only (no support for older versions of .NET!)
• Support for ILogger See #4
• Support for diagnostic events using ActivitySource and Activity See #3
• Using the latest .NET features like Span<T> and Memory<T> to improve performance
• Update dependencies to the latest versions
• TLS 1.2 and TLS 1.3 only support
• Modern Event System: Event-handlers with HttpRequestMessage and HttpResponseMessage, to greatly improve the portability of the library See #6
• HttpClient as the default client, and using the IHttpClientFactory to handle pooling of the clients
• Testing, testing, testing!

Modern Event System

This proxy server uses a modern, clean event system based on standard HttpRequestMessage and HttpResponseMessage objects, making it easier to integrate with existing .NET HTTP libraries and patterns.

Request Interception

var events = new ProxyServerEvents();
events.OnRequest += async (sender, e, cancellationToken) =>
{
    Console.WriteLine($"Request: {e.Request.Method} {e.Request.RequestUri}");
    
    // Block specific domains
    if (e.Request.RequestUri?.Host.Contains("blocked.com") == true)
    {
        var blockedResponse = new HttpResponseMessage(HttpStatusCode.Forbidden)
        {
            Content = new StringContent("Access Denied")
        };
        return RequestEventResponse.EarlyResponse(blockedResponse);
    }
    
    // Modify request headers
    e.Request.Headers.Add("X-Proxy-Agent", "Unobtanium");
    
    // Redirect requests
    if (e.Request.RequestUri?.Host.Contains("example.com") == true)
    {
        var redirectedRequest = new HttpRequestMessage(e.Request.Method, "https://microsoft.com")
        {
            Content = e.Request.Content,
            Version = e.Request.Version
        };
        
        // Copy headers
        foreach (var header in e.Request.Headers)
        {
            redirectedRequest.Headers.TryAddWithoutValidation(header.Key, header.Value);
        }
        
        return RequestEventResponse.ModifyRequest(redirectedRequest);
    }
    
    return RequestEventResponse.ContinueResponse();
};

Response Interception

events.OnResponse += async (sender, e, cancellationToken) =>
{
    Console.WriteLine($"Response: {e.Response.StatusCode} from {e.Request.RequestUri}");
    
    // Modify responses
    if (e.Response.Content != null)
    {
        var content = await e.Response.Content.ReadAsStringAsync(cancellationToken);
        if (content.Contains("error"))
        {
            var modifiedResponse = new HttpResponseMessage(HttpStatusCode.OK)
            {
                Content = new StringContent(content.Replace("error", "success")),
                Version = e.Response.Version
            };
            
            // Copy headers
            foreach (var header in e.Response.Headers)
            {
                modifiedResponse.Headers.TryAddWithoutValidation(header.Key, header.Value);
            }
            
            return ResponseEventResponse.ModifyResponse(modifiedResponse);
        }
    }
    
    return ResponseEventResponse.ContinueResponse();
};

Features

• API Documentation
• Wiki & Contribution guidelines
• Multithreaded and asynchronous proxy employing server connection pooling, certificate cache, and buffer pooling
• View, modify, redirect and block requests or responses
• Modern event system based on HttpRequestMessage and HttpResponseMessage

Installation

Package on NuGet, Unobtanium.Web.Proxy will be a partial drop-in replacement for Titanium.Web.Proxy, if you're on NET8.0 or higher.

dotnet add package Unobtanium.Web.Proxy

Supports

• .NET 8.0 and above

As stated above, this project is a reboot of the original project. Expect things to change, everything marked as obsolete in the original project will be removed in this project. And until this is v1.0.0, expect breaking changes.

Usage

using Unobtanium.Web.Proxy;
using Unobtanium.Web.Proxy.Events;
var events = new ProxyServerEvents();
events.ShouldDecryptNewConnection = async (host, cts) =>
{
    // Log the new connection details
    return host.Equals("graph.microsoft.com");
};
events.OnRequest += async (s, e, cancellationToken) =>
{
    Console.WriteLine($"Request to: {e.Request.RequestUri}");
    if (e.Request.RequestUri.ToString().StartsWith("https://graph.microsoft.com/v1.0/"))
    {
        var content = @"What ever you want";
        var response = new HttpResponseMessage {
            StatusCode = System.Net.HttpStatusCode.Unauthorized,
            Content = new StringContent(content, System.Text.Encoding.UTF8, "application/json")
        };
        return Unobtanium.Web.Proxy.Events.RequestEventResponse.EarlyResponse(response);
    }
    return Unobtanium.Web.Proxy.Events.RequestEventResponse.ContinueResponse();
};

events.OnResponse += async (s, e, cancellationToken) =>
{
    Console.WriteLine($"Response from: {e.Request.RequestUri}");
    //if (e.Response.Content is not null)
    //{
    //    var body = await e.Response.Content!.ReadAsStringAsync(cancellationToken);
    //    Console.WriteLine(body);
    //}
    return ResponseEventResponse.ContinueResponse();
};

builder.Services.AddProxyEvents(events);

builder.Services.AddProxyServices();

Complete Example

Check out the worker template for a complete example of how to use the proxy server in a .NET worker service.

Creator

Since this ended up to be a full rewrite I'll put myself as owner:

• svrooij

You contributions are more then welcome! Let's make this project great again!

Previous Collaborators

The previous owner of this project, justcoding121, is considered to be inactive from this project due to his busy work schedule. See project reboot for more information.

Previous contributors:

• justcoding121 owner
• honfika

Development environment

Since this is a dotnet project I would suggest to use Visual Studio 2022 or Visual Studio Code as your development environment. The project is set up to use the dotnet CLI, so you can also use that to build and run the project.