🧩 ToDoApp - gRPC API Examples (Layered Architecture)

This repository demonstrates multiple gRPC API implementations for a simple ToDo application using .NET 9 and layered architecture. Each project showcases a different style or feature of gRPC communication.

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Author

Vishwa Kumar

• Email: vishwa@vishwa.me
• GitHub: Vishwam
• LinkedIn: Vishwa Kumar

Vishwa is the primary architect of the ToDoApp, responsible for the architecture and implementation of these features.

📦 Included Projects

1. ToDoApp.Data.Sqlite

Data Access Layer
Implements Entity Framework Core using a local SQLite database. This layer contains the data model, DbContext, and the ToDoItem repository used by both gRPC APIs.

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2. ToDoApp.GrpcApi.Native

Pure gRPC Service (No JSON Transcoding)
Implements gRPC endpoints defined in .proto files for managing ToDo items. Designed for internal or high-performance communication between microservices.

• ✅ High performance
• ❌ No Swagger / REST compatibility
• ✅ Supports tools like grpcurl, Postman (with .proto or reflection)
• 🚫 Not human-readable over HTTP (binary protocol)

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3. ToDoApp.GrpcApi.Transcoding

gRPC with REST-style JSON Transcoding
Uses Grpc.AspNetCore.GrpcJsonTranscoding to expose the same gRPC service as a RESTful JSON API. Great for scenarios where external clients (e.g., frontends, mobile apps) need to use HTTP/JSON.

• ✅ gRPC and REST with single implementation
• ✅ Swagger/OpenAPI documentation available (accessible at /swagger when running)
• ✅ Usable in Postman and Swagger UI
• ✅ gRPC reflection enabled for easy service discovery
• 📦 Slightly higher overhead due to transcoding

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✅ Key Features

• Built on .NET 9 using a layered architecture
• Shared EF Core Data Layer for both gRPC APIs
• Local SQLite DB for ease of testing and development
• Easy-to-run and test each service independently
• Can be extended to include auth, validation, and advanced patterns (e.g., CQRS)

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🛠️ How to Run

Each project contains its own .sln file so you can run them independently from Visual Studio or the CLI.

To run a project:

cd grpc-apis.styles.examples/src/ToDoApp.GrpcApi.Native   # or ToDoApp.GrpcApi.Transcoding
dotnet run

For Native gRPC:

• Use gRPC clients or tools like grpcurl or Postman (with gRPC support)
• gRPC reflection is enabled for service discovery

For Transcoding:

• Access Swagger UI at http://localhost:<port>/swagger (port configured in launchSettings.json)
• Can be tested with standard HTTP/REST clients
• Also supports native gRPC clients

Prerequisites

• .NET SDK 9+
• Visual Studio 2022 or VS Code
• EF Core tools (if working with migrations)

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🔍 Goals

• Help developers understand different gRPC API implementation patterns.
• Enable experimentation and benchmarking.
• Provide a base for extending to Clean Architecture or CQRS in the future.

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📌 Roadmap

• Add MediatR-based APIs
• Add Clean Architecture sample

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📄 License

This project is licensed under the MIT License.