Dameng.Protobuf.Extension.Generator 0.1.2

Dameng.Protobuf.Extension

A .NET library that enables generic protobuf deserialization by providing an interface and source generator for Google.Protobuf generated classes. Designed as a NativeAOT-compatible alternative to protobuf-net for applications requiring ahead-of-time compilation.

Overview

This library allows you to write generic deserialization functions for protobuf messages without knowing the specific type at compile time. It achieves this by adding a IPbMessageParser<TSelf> interface to protobuf generated classes through source generation.

Why Choose This Over protobuf-net?

This library is specifically designed for NativeAOT compatibility, making it an ideal replacement for protobuf-net in scenarios where ahead-of-time compilation is required. Unlike protobuf-net, which relies heavily on reflection and runtime code generation, this solution uses source generation to provide the same generic capabilities with full NativeAOT support.

Features

• Generic Deserialization: Write type-safe generic methods for protobuf deserialization
• Source Generator: Automatically implements the interface for all protobuf generated classes
• Zero Runtime Overhead: All code generation happens at compile time
• Easy Integration: Just add the NuGet packages and configure your protobuf files
• NativeAOT Compatible: Full support for ahead-of-time compilation scenarios
• protobuf-net Migration: Smooth transition path from protobuf-net for NativeAOT projects

Installation

Install both packages from NuGet:

dotnet add package Dameng.Protobuf.Extension
dotnet add package Dameng.Protobuf.Extension.Generator

Migration & Usage

Quick Start

Add the required packages:

dotnet add package Google.Protobuf
dotnet add package Dameng.Protobuf.Extension
dotnet add package Dameng.Protobuf.Extension.Generator

Configure your .csproj with protobuf files:

<ItemGroup>
  <ProtoBuf Include="your-proto-file.proto">
    <GrpcServices>Client</GrpcServices>
    <Generator>MSBuild:PreCompile</Generator>
  </ProtoBuf>
</ItemGroup>

Write generic methods that work with any protobuf message:

using Dameng.Protobuf.Extension;
using Google.Protobuf;

// Generic deserialization
T Deserialize<T>(byte[] bytes) where T : IPbMessageParser<T>, IMessage<T>
{
    return T.Parser.ParseFrom(bytes);
}

// Generic serialization  
byte[] Serialize<T>(T message) where T : IPbMessageParser<T>, IMessage<T>
{
    return message.ToByteArray();
}

// Usage with any protobuf generated class
var request = Deserialize<MyRequest>(requestBytes);
var response = Deserialize<MyResponse>(responseBytes);

Migrating from protobuf-net

Why migrate? protobuf-net has limited NativeAOT support due to heavy reflection usage, while this library provides full compatibility through compile-time source generation.

Migration steps:

1. Replace protobuf-net with Google.Protobuf + this extension
2. Convert protobuf-net attributes to standard .proto files:

   // Standard .proto file
   syntax = "proto3";
   message MyMessage {
     string name = 1;
   }
   

3. Update generic code constraints from where T : class, new() to where T : IPbMessageParser<T>, IMessage<T>

Key differences:

How It Works

The source generator automatically implements IPbMessageParser<TSelf> on all protobuf generated classes, exposing their static Parser property for generic access:

// Auto-generated for each protobuf class
partial class MyRequest : IPbMessageParser<MyRequest> {}

Example: Generic Communication Handler

public class GenericProtobufHandler
{
    public T HandleMessage<T>(byte[] messageBytes) 
        where T : IPbMessageParser<T>, IMessage<T>
    {
        return T.Parser.ParseFrom(messageBytes);
    }
    
    public byte[] SerializeMessage<T>(T message) 
        where T : IPbMessageParser<T>, IMessage<T>
    {
        return message.ToByteArray();
    }
}

Requirements

• .NET 8.0 or higher
• Google.Protobuf package
• C# 11.0 or higher (for generic static interface members)
• NativeAOT Compatible: Full support for ahead-of-time compilation when using <PublishAot>true</PublishAot>

License

MIT License - see LICENSE file for details.

Contributing

Contributions are welcome! Please feel free to submit issues and pull requests.