A C# based websocket server designed for high throughput, efficiency, and modularization.
- .NET Standard 2.0
This project is currently in active development. As such, please think twice before using it in production! For a more mature project, please take a look at WebSocket-Sharp.
The reason for the creation of this project comes mainly from frustration with existing projects (isn't that always how it is?). The particularly use case for Loki's creation is to implement a WebSocket server which would scale well, accept modular drop-ins for enhancing the engine, and be RFC 6455 compliant.
For minimum setup, you need to do two things. The first is to create the default route.
using Loki.Common.Events;
using Loki.Interfaces.Connections;
using Loki.Interfaces.Logging;
using Loki.Server.Attributes;
using Loki.Server.Data;
namespace LokiCoreServer.Routes
{
[ConnectionRoute("/")]
public class Default : WebSocketDataHandler
{
public override void OnOpen(IWebSocketConnection sender, ConnectionOpenedEventArgs args)
{
Logger.Info($"JOIN {sender.UniqueIdentifier}/{sender.ClientIdentifier}");
base.OnOpen(sender, args);
}
public override void OnClose(IWebSocketConnection sender, ConnectionClosedEventArgs args)
{
Logger.Info($"QUIT {sender.UniqueIdentifier}/{sender.ClientIdentifier}");
base.OnClose(sender, args);
}
public override void OnText(IWebSocketConnection sender, TextFrameEventArgs args)
{
Logger.Debug($"RECV {sender.UniqueIdentifier}/{sender.ClientIdentifier} {args.Message.Length * 2} bytes");
//Respond with the same text
sender.SendText(args.Message);
base.OnText(sender, args);
}
public Default(ILogger logger) : base(logger)
{
Logger.Debug("Route created: / => Default");
}
}
}This tells the server that any request that comes in with the / route will be handled by that particular WebSocketDataHandler. The route object is subscribed to a multitude of events. It handles both text and binary transmissions as well as partial and full frames. Loki can also handle multiple routes per server instance. The routes are picked up through reflection on server start by annotating the class with the ConnectionRoute attribute.
The next step is instantiating the server itself. The code below binds the server to any IPv4 address available.
using System;
using System.Net;
using Loki.Interfaces;
using Loki.Server;
namespace LokiCoreServer
{
class Program
{
static void Main(string[] args)
{
//Set port and host
int port = Convert.ToInt32(1337);
IPAddress host = IPAddress.Parse("0.0.0.0");
//Start the server
using (IServer server = new Server("MyServerName", host, port))
{
//Start listening and blocking the main thread
server.Run();
}
}
}
}To combat some of the difficulty around unit testing a networked application, and to avoid having needless dependencies; Loki uses its own very simplistic DI class called DependencyUtility. It is passed into requisite classes via its interface IDependencyUtility.
using System;
using System.Net;
using Loki.Common.Events;
using Loki.Interfaces;
using Loki.Interfaces.Dependency;
using Loki.Interfaces.Logging;
using Loki.Server.Dependency;
using Loki.Server.Logging;
namespace Loki.Example.Logging
{
class Program
{
static void Main(string[] args)
{
//Create our log wrapper
ILogger logger = new Logger();
//Create our dependency utility and register the logger
IDependencyUtility dependencyUtility = new DependencyUtility();
dependencyUtility.Register<ILogger>(logger);
//Set port and host
int port = Convert.ToInt32(1337);
IPAddress host = IPAddress.Parse("0.0.0.0");
//Start the server
using (IServer server = new Server.Server("MyServerName", host, port, dependencyUtility))
{
//Start listening and blocking the main thread
server.Run();
}
}
}
}Loki comes equipped with an event-based logging class which you can use with a pre-existing library like Log4Net or roll your own.
using System;
using System.Net;
using Loki.Common.Events;
using Loki.Interfaces;
using Loki.Interfaces.Dependency;
using Loki.Interfaces.Logging;
using Loki.Server.Dependency;
using Loki.Server.Logging;
namespace Loki.Example.Logging
{
class Program
{
static void Main(string[] args)
{
//Create our log wrapper and events
ILogger logger = new Logger();
logger.OnError += OnError;
logger.OnDebug += OnDebug;
logger.OnWarn += OnWarn;
logger.OnInfo += OnInfo;
//Create our dependency utility and register the logger
IDependencyUtility dependencyUtility = new DependencyUtility();
dependencyUtility.Register<ILogger>(logger);
//Set port and host
int port = Convert.ToInt32(1337);
IPAddress host = IPAddress.Parse("0.0.0.0");
//Start the server
using (IServer server = new Server.Server("MyServerName", host, port, dependencyUtility))
{
//Start listening and blocking the main thread
server.Run();
}
}
private static void OnError(object sender, LokiErrorEventArgs e)
{
Console.ForegroundColor = ConsoleColor.Red;
Console.WriteLine($"[{e.EventTimeStamp}]\tERROR\t{e.Exception}");
Console.ResetColor();
}
private static void OnDebug(object sender, LokiDebugEventArgs e)
{
Console.ForegroundColor = ConsoleColor.White;
Console.WriteLine($"[{e.EventTimeStamp}]\tDEBUG\t{e.Message}");
Console.ResetColor();
}
private static void OnInfo(object sender, LokiInfoEventArgs e)
{
Console.ForegroundColor = ConsoleColor.White;
Console.WriteLine($"[{e.EventTimeStamp}]\tDEBUG\t{e.Message}");
Console.ResetColor();
}
private static void OnWarn(object sender, LokiWarnEventArgs e)
{
Console.ForegroundColor = ConsoleColor.Yellow;
Console.WriteLine($"[{e.EventTimeStamp}]\tWARN\t{e.Message}");
Console.ResetColor();
}
}
}Loki can consume an X509Certificate2 object via an ISecurityContainer to encrypt client to server traffic.
using System;
using System.Net;
using System.Security.Authentication;
using System.Security.Cryptography.X509Certificates;
using Loki.Interfaces;
using Loki.Interfaces.Dependency;
using Loki.Interfaces.Security;
using Loki.Server.Dependency;
using Loki.Server.Security;
namespace Loki.Example.Secure
{
class Program
{
static void Main(string[] args)
{
//Create our dependency utility
IDependencyUtility dependencyUtility = new DependencyUtility();
//Create our security container
ISecurityContainer securityContainer = GenerateSecurityContainer();
//Register dependencies
dependencyUtility.Register<ISecurityContainer>(securityContainer);
//Set port and host
int port = Convert.ToInt32(1337);
IPAddress host = IPAddress.Parse("0.0.0.0");
//Start the server
using (IServer server = new Server.Server("MyServerName", host, port, dependencyUtility))
{
//Start listening and blocking the main thread
server.Run();
}
}
private static ISecurityContainer GenerateSecurityContainer()
{
X509Certificate2 certificate = new X509Certificate2("path/to/cert.pfx", "pfxpassword");
//Certificate, Protocols, ClientCertRequired?, CertificateRevokationEnabled?, Enabled?
return new SecurityContainer(certificate, SslProtocols.Tls | SslProtocols.Tls11 | SslProtocols.Tls12, false, true, true);
}
}
}