# dotnet-cqrs

> Modern CQRS implementation for .NET 10 with HTTP and gRPC endpoint generation.

## Purpose

Svrnty.CQRS provides a framework for implementing the Command Query Responsibility Segregation pattern in .NET applications. It automatically generates HTTP endpoints (via Minimal API) and gRPC service implementations (via source generators) from registered command and query handlers.

## What It Does

- **Automatic HTTP endpoints** — registers handlers, generates REST endpoints at startup
- **Automatic gRPC services** — source-generated service implementations from .proto files
- **Dynamic queries** — OData-like filtering, sorting, grouping, and aggregation
- **Validation** — FluentValidation with RFC 7807 (HTTP) and Google Rich Error Model (gRPC)
- **Dual protocol** — same handlers serve both HTTP and gRPC simultaneously

## How It Works

1. Define a command/query as a C# class
2. Implement a handler (`ICommandHandler<T>` or `IQueryHandler<T, R>`)
3. Register with DI: `services.AddCommand<T, Handler>()`
4. Framework creates metadata and discovery services at startup
5. `MapSvrntyCommands()` generates HTTP endpoints; `MapGrpcService<>()` maps gRPC services

## Key Concepts

| Term | Meaning |
|------|---------|
| Command | An action that changes state (always POST) |
| Query | A request for data (POST or GET) |
| Discovery | Runtime service that enumerates all registered commands/queries |
| Source Generator | Compile-time code generation for gRPC service implementations |
| Dynamic Query | OData-like filtering with IQueryable providers and interceptors |

## Current Status

| Phase | Status | Description |
|-------|--------|-------------|
| 0 | Done | Core CQRS, Minimal API, FluentValidation |
| 1 | Done | gRPC support, source generators |
| 2 | Done | Dynamic queries, dual protocol |
| 3 | Planned | Test suite, AOT compatibility |