Carter

Carter is a library that allows Nancy-esque routing for use with ASP.Net Core.

This is not a framework, it simply builds on top of Microsoft.AspNetCore.Routing allowing you to have more elegant routing rather than have attribute routing, convention routing, ASP.Net Controllers or IRouteBuilder extensions.

For a better understanding, take a good look at the samples inside this repo. The sample demonstrates usages of elegant extensions around common ASP.Net Core types as shown below.

Other extensions include:

Bind/BindAndValidate<T> - FluentValidation extensions to validate incoming HTTP requests.
BindFile/BindFiles/BindFileAndSave/BindFilesAndSave - Allows you easily get access to a file/files that has been uploaded or alternatively you can call BindFilesAndSave and this will save it to a path you specify
Global Before/After hooks for every request.
Before/After hooks to the routes defined in a Carter module.
Routes to use in common ASP.Net Core middleware eg. app.UseExceptionHandler("/errorhandler");.
IStatusCodeHandlers are also an option as the ASP.Net Core UseStatusCodePages middleware is not elegant enough IMO. IStatusCodeHandlers allow you to define what happens when one of your routes returns a specific status code. An example usage is shown in the sample.
IResponseNegotiators allow you to define how the response should look on a certain Accept header. Handling JSON is built in and the default response but implementing an interface allows the user to choose how they want to represent resources.
All interface implementations are registered into ASP.Net Core DI automatically, implement the interface and off you go.

Supports two different routing APIs.

(i)

this.Get("/actors/{id:int}", async (req, res, routeData) =>
{
    var person = actorProvider.Get(routeData.As<int>("id"));
    await res.Negotiate(person);
});

(ii)

this.Get("/actors/{id:int}", async (ctx) =>
{
    var person = actorProvider.Get(ctx.GetRouteData().As<int>("id"));
    await ctx.Response.Negotiate(person);
});

Where does the name "Carter" come from?

I have been a huge fan of, and core contributor to Nancy, the best .Net web framework, for many years, and the name "Nancy" came about due to it being inspired from Sinatra the Ruby web framework. Frank Sinatra had a daughter called Nancy and so that's where it came from.

I was also trying to think of a derivative name, and I had recently listened to the song Empire State of Mind where Jay-Z declares he is the new Sinatra. His real name is Shaun Carter so I took Carter and here we are!

Getting Started

You can get started using either the template or by adding the package manually to a new or existing application

Template

https://www.nuget.org/packages/CarterTemplate/

Install the template - dotnet new -i CarterTemplate
Create a new application using template - dotnet new Carter -n MyCarterApp
Run the application - dotnet run

Package

https://www.nuget.org/packages/Carter

Create a new empty ASP.NET Core application - dotnet new web -n MyCarterApp
Change into the new project location - cd ./MyCarterApp
Add Carter package - dotnet add package carter
Modify your Startup.cs to use Carter

public class Startup
{
    public void ConfigureServices(IServiceCollection services)
    {
        services.AddCarter();
    }

    public void Configure(IApplicationBuilder app)
    {
        app.UseCarter();
    }
}

Create a new Module

    public class HomeModule : CarterModule
    {
        public HomeModule()
        {
            Get("/", async (req, res, routeData) => await res.WriteAsync("Hello from Carter!"));
        }
    }

Run the application - dotnet run

Sample

public class Startup
{
    public void ConfigureServices(IServiceCollection services)
    {
        services.AddSingleton<IActorProvider, ActorProvider>();
        services.AddCarter();
    }

    public void Configure(IApplicationBuilder app)
    {
        app.UseCarter();
    }
}

public class ActorsModule : CarterModule
{
    public ActorsModule(IActorProvider actorProvider)
    {
        this.Get("/actors", async (req, res, routeData) =>
        {
            var people = actorProvider.Get();
            await res.AsJson(people);
        });

        this.Get("/actors/{id:int}", async (req, res, routeData) =>
        {
            var person = actorProvider.Get(routeData.As<int>("id"));
            await res.Negotiate(person);
        });

        this.Put("/actors/{id:int}", async (req, res, routeData) =>
        {
            var result = req.BindAndValidate<Actor>();

            if (!result.ValidationResult.IsValid)
            {
                res.StatusCode = 422;
                await res.Negotiate(result.ValidationResult.GetFormattedErrors());
                return;
            }

            // Update the user in your database

            res.StatusCode = 204;
        });

        this.Post("/actors", async (req, res, routeData) =>
        {
            var result = req.BindAndValidate<Actor>();

            if (!result.ValidationResult.IsValid)
            {
                res.StatusCode = 422;
                await res.Negotiate(result.ValidationResult.GetFormattedErrors());
                return;
            }

            // Save the user in your database

            res.StatusCode = 201;
            await res.Negotiate(result.Data);
        });

    }
}