TnTResult Solution

TnTResult is a .NET solution providing a set of libraries for handling result types, error handling, and HTTP integration in C# applications. It is designed to improve code clarity, error propagation, and integration with ASP.NET Core and Refit-based APIs.

Table of Contents

• Projects Overview
• Build Instructions
• Running Tests
• Usage Examples
  • TnTResult
  • TnTResult.AspNetCore.Http
  • TnTResult.Refit
• License

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Projects Overview

1. TnTResult

• Purpose:
  • Core library for result types (Expected, Optional, etc.), error handling, and utility extensions.
  • Provides a functional approach to handling success/failure and optional values.
• Key Files:
  • Expected.cs, Optional.cs, TnTResult.cs, TnTFileDownload.cs
  • Extensions in Ext/
  • Custom exceptions in Exceptions/

2. TnTResult.AspNetCore.Http

• Purpose:
  • Integrates TnTResult types with ASP.NET Core HTTP pipeline.
  • Provides helpers for controller responses and HTTP result mapping.
• Key Files:
  • ControllerRepositoryBase.cs, HttpTnTResult.cs
  • Extensions in Ext/

3. TnTResult.Refit

• Purpose:
  • Adds support for using TnTResult types with Refit (a REST library for .NET).
  • Provides extension methods for working with IApiResponse and mapping API results.
• Key Files:
  • Extensions in Ext/

4. TnTResult.Tests

• Purpose:
  • Contains unit tests for all core and extension libraries.
  • Organized by subproject and feature.

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Build Instructions

1. Prerequisites:

   • .NET 8.0 SDK or newer
   • (Optional) Visual Studio 2022+ or VS Code

2. Restore dependencies:

   dotnet restore TnTResult.sln

3. Build the solution:

   dotnet build TnTResult.sln --configuration Release

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Running Tests

All tests are located in the TnTResult.Tests project. To run all tests:

dotnet test TnTResult.sln

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Usage Examples

TnTResult

using TnTResult;

// --- Expected usage ---
var ok = Expected.MakeExpected<int, string>(42);
if (ok.HasValue)
{
    Console.WriteLine($"Value: {ok.Value}");
}
else
{
    Console.WriteLine($"Error: {ok.Error}");
}

var err = Expected.MakeUnexpected<int, string>("Something went wrong");
if (!err.HasValue)
{
    Console.WriteLine($"Error: {err.Error}");
}

// --- Optional usage ---
var some = Optional.MakeOptional("hello");
if (some.HasValue)
{
    Console.WriteLine($"Optional value: {some.Value}");
}

var none = Optional.NullOpt<string>();
if (none.IsEmpty)
{
    Console.WriteLine("Optional is empty");
}

// --- ITnTResult usage ---
ITnTResult result = TnTResult.Successful;
result
    .OnSuccess(() => Console.WriteLine("Operation succeeded!"))
    .OnFailure(ex => Console.WriteLine($"Operation failed: {ex.Message}"))
    .Finally(() => Console.WriteLine("Operation finished (success or failure)"));

// ITnTResult<T> usage
ITnTResult<string> result2 = TnTResult.Success("Hello");
result2
    .OnSuccess(val => Console.WriteLine($"Success value: {val}"))
    .OnFailure(ex => Console.WriteLine($"Failed: {ex.Message}"))
    .Finally(() => Console.WriteLine("Done!"));

// --- Async usage with extension methods ---
using TnTResult.Ext;
await Task.FromResult(TnTResult.Successful)
    .OnSuccessAsync(() => Console.WriteLine("Async success!"));

await Task.FromResult(TnTResult.Failure(new Exception("fail")))
    .OnFailureAsync(ex => Console.WriteLine($"Async failure: {ex.Message}"));

TnTResult.AspNetCore.Http

using TnTResult.AspNetCore.Http;
using TnTResult;
using Microsoft.AspNetCore.Mvc;

// Inherit from TnTResultControllerBase to use static helpers
// Return ITnTResult from your actions—the base class will automatically convert it to an appropriate IResult for ASP.NET Core.
public class MyController : TnTResultControllerBase
{
    [HttpGet("/created")]
    public ITnTResult CreatedExample()
    {
        // Use the static SuccessfullyCreated property
        return SuccessfullyCreated;
    }

    [HttpGet("/forbidden")]
    public ITnTResult ForbiddenExample()
    {
        // Use the static FailureForbidden property
        return FailureForbidden;
    }

    [HttpGet("/conflict")]
    public ITnTResult ConflictExample()
    {
        // Use the static Conflict helper
        return Conflict("A conflict occurred");
    }

    [HttpGet("/custom-created")]
    public ITnTResult CustomCreatedExample()
    {
        // Use the static Created<T> helper for a custom value
        return Created("Resource created!");
    }
}

// Note: TnTResultControllerBase will automatically convert any ITnTResult returned from your action
// into the correct ASP.NET Core IResult (status code, body, etc.) for the HTTP response.

TnTResult.Refit

using TnTResult.Refit.Ext;
using Refit;

public interface IMyApi
{
    [Get("/data")]
    Task<IApiResponse<string>> GetDataAsync();
}

// Usage in your code:
var apiResponse = await myApi.GetDataAsync();
var result = apiResponse.ToTnTResult();
if (result.IsSuccess)
{
    Console.WriteLine($"API value: {result.Value}");
}
else
{
    Console.WriteLine($"API error: {result.Error.Message}");
}

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License

This project is licensed under the MIT License. See LICENSE for details.