Andrew.CommonUse.OAuth 1.0.5

# Andrew.CommonUse.OAuth

A lightweight and extensible **OAuth 2.0 integration framework** for .NET applications.  
Provides a unified interface to handle multiple OAuth providers such as **Google**, **GitHub**, **Microsoft**, and more.  
(Currently supports **Google**, with more providers coming soon.)

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## 🚀 Features

- ✅ Simple and clean API for **Google OAuth 2.0**
- 🧩 Unified OAuth interface across multiple providers
- ⚙️ Configuration-driven via `appsettings.json`
- 🧠 Fully supports **Dependency Injection** and `IOptions<T>`
- 🔒 Built-in state validation and secure token exchange
- 🧪 Designed for easy unit testing and mocking
- 🔧 Easily extendable for future providers (GitHub, Microsoft, Facebook, etc.)

---

## 📦 Installation

Install via NuGet:

```bash
dotnet add package Andrew.CommonUse.OAuth

⚙️ Configuration

Add your OAuth settings to appsettings.json:

{
  "OAuth": {
    "Google": {
      "AuthUrl": "https://accounts.google.com/o/oauth2/v2/auth",
      "TokenUrl": "https://oauth2.googleapis.com/token",
      "ClientId": "YOUR_CLIENT_ID",
      "ClientSecret": "YOUR_CLIENT_SECRET",
      "RedirectUrl": "https://localhost:5001/api/auth/callback",
      "Scope": "profile email"
    }
  }
}

🧩 Usage Example

1️⃣ Register OAuth service in DI

builder.Services.AddOAuthService(builder.Configuration);

2️⃣ Inject and use the service

public class OAuthController(
    [FromKeyedServices(OAuthProviderEnum.Google)] IOAuthService googleOAuthService
) : ControllerBase
{
  
//get GetAuthorizationUrl
        var state = Guid.NewGuid().ToString();
        var authUrl = googleOAuthService.GetAuthorizationUrl(state);
 
 // get callback userinfo
    // GET: api/auth/callback
    [HttpGet("callback")]
    public async Task<IActionResult> Callback(string state, string code, string error = "")
    {
        var response = await googleOAuthService.OAuthCallBack(state, code, error);
        if (!response.Success)
            return BadRequest(response.ErrorMsg);

        return Ok(response.UserInfo);
    }
}

3️⃣ Example output

Visit this URL to authorize: https://accounts.google.com/o/oauth2/v2/auth?...
User Info: {"Id":"12345","Email":"user@gmail.com","Name":"John Doe"}

🧰 Extend to Other Providers

Implement your own provider by inheriting from IOAuthService and configuring new endpoints in appsettings.json. Each provider can define its own:

• Authorization URL
• Token URL
• User Info URL
• Client credentials and scopes

🌐 Links

• NuGet: Andrew.CommonUse.OAuth
• GitHub: https://github.com/sharisp/OAuth2Service

⭐ If you find this project helpful, please give it a star on GitHub!

---

## 💡 Optional Additions

You could add:
1. **Badges** (NuGet, build status, license, etc.)
   ```markdown
   [![NuGet](https://img.shields.io/nuget/v/Andrew.CommonUse.OAuth.svg)](https://www.nuget.org/packages/Andrew.CommonUse.OAuth)
   [![License](https://img.shields.io/github/license/sharisp/OAuth2Service.svg)](LICENSE)

2. Roadmap or To-Do section

   ## 🛣️ Roadmap
   - [x] Google OAuth support  
   - [ ] GitHub OAuth support  
   - [ ] Microsoft OAuth support  
   - [ ] Facebook OAuth support