LiteSpeedLink: The .NET lightweight, compile-time, contract-first and source generated communication framework

Introduction

This project implements a custom API communication channel using the UDP, TCP or QUIC. The communication model is contract-first, with two primary implementation variants: Minimal and Class-first, totally source generated

Key Concepts

• Contract-First: Both endpoints, host and client must define implementors, either service interfaces or delegates.
• Hosts: Server implementations ready to receive any client message.
• Clients: IConnection implementations ready to chat with any implemented server preiously mentioned.
• Communication Contracts: Defined using source generation with two variants:
  • Minimal Variant: Methods are declared in Program.cs with attribute markers (EndpointHandlerAttribute).
  • Class Variant: Methods inside classes implementing interfaces inheriting IServiceUnit.

Host Service side

Host service partial classes are generated when they have the ServiceHostAttribute together with any of the following attributes from the Jab library:

• TransientAttribute<TInterface, TImplementation>
• TransientAttribute<TImplementation>
• ScopedAttribute<TInterface, TImplementation>
• ScopedAttribute<TImplementation>
• SingletonAttribute<TInterface, TImplementation>
• SingletonAttribute<TImplementation>

These attributes should be applied to the class owning the ServiceHostAttribute.

Example

[ServiceHost]
[Singleton<IMySingletonService, MySingletonService>]
[Scoped<IMyScopedService, MyScopedService>]
[Transient<IMyTransientService, MyTransientService>]
public partial class MyHostService;

EndpointHandlerAttribute

Used in the minimal variant to declare service methods.

Example

Every method in Program.cs marked with EndpointHandlerAttribute will serve as host endpoint (a dedicated delegate will be registered)

Program.cs

[ServiceHost]
// other services...
public partial class MyHostService;

[EndpointHandler]
internal async ValueTask<bool> SaveConfigurationAsync(string key, string value, [Service] IConfigurationManager configManager = default!, CancellationToken token = default)
{
  return await configManager.CreateOrUpdateAsync(key, value, token);
}

IServiceUnit

Interfaces inheriting this must implement the service endpoints.

Example

public interface IProductServiceUnit : IServiceUnit
{
    async ValueTask<CreatedProduct> CreateProductAsync(NewProductMessage message);
}

Host-Client side

To generate clients you just must add interfaces defined in contracts or minimal variant generated delegates to service client class (owning ServiceClientAttribute),

[ServiceClient]
public partial class MyClientService : IMyService, IServiceHandler<CreateProductAsync>;

Dependencies

This project uses the following libraries:

• System.IO.Pipelines: For managing bytes sequences to be serialized/sdeserialized.
• Jab: For dependency injection and service management.

TODO

• Pipeline implementation for middlewares
• Binary mappers (a fork of SourceCrafter)
• Streaming processor (suitable for gaming, duplex services and real-time communication)