SimpleResults.AspNetCore 0.1.1-alpha

SimpleResults

A simple library to implement the Result pattern for returning from services.

This library was inspired by Arcadis.Result.

Installation

Run the following command from the terminal:

dotnet add package SimpleResults --prerelease

Or you can also install the package for ASP.NET Core:

dotnet add package SimpleResults.AspNetCore --prerelease

Usage

This example is simple and is based on the EF Core introductory tutorial.

using SimpleResults;

public class BlogService
{
    private readonly BloggingContext _db;

    public BlogService(BloggingContext db)
    {
        _db = db;
    }

    public Result<CreatedId> Create(string url)
    {
        if(string.IsNullOrWhiteSpace(url))
        {
            return Result.Invalid();
        }

        var blog = new Blog { Url = "http://blogs.msdn.com/adonet" };
        _db.Add(blog);
        _db.SaveChanges();
        return Result.CreatedResource(blog.BlogId);
    }

    public Result<Blog> Read(int id)
    {
        if(id < 0)
        {
            return Result.Invalid("ID must not be negative");
        }

        var blog = _db.Blogs
            .Where(b => b.BlogId == id)
            .FirstOrDefault();

        if(blog is null)
        {
            return Result.NotFound();
        }

        return Result.Success(blog);
    }
}

This approach provides a new way to handle error without the need to use exceptions.

Integration with ASP.NET Core

You can convert the Result object to an ActionResult, such as:

using SimpleResults;

public class BlogRequest 
{ 
    public string Url { get; init; }
}

[ApiController]
[Route("[controller]")]
public class BlogController : ControllerBase
{
    private readonly BlogService _blogService;

    public BlogController(BlogService blogService)
    {
        _blogService = blogService;
    }

    [HttpGet("{id}")]
    public ActionResult<Result<Blog>> Get(int id)
    {
        return _blogService
            .Read(id)
            .ToActionResult();
    }

    [HttpPost]
    public ActionResult<Result<CreatedId>> Create([FromBody]BlogRequest request)
    {
        return _blogService
            .Create(request.Url)
            .ToActionResult();
    }
}

You can find a complete and functional example in these projects:

• SimpleResults.Example
• SimpleResults.Example.AspNetCore

Contribution

Any contribution is welcome! Remember that you can contribute not only in the code, but also in the documentation or even improve the tests.

Follow the steps below:

• Fork it
• Create your feature branch (git checkout -b my-new-feature)
• Commit your changes (git commit -am 'Added some feature')
• Push to the branch (git push origin my-new-feature)
• Create new Pull Request