StrongOf.AspNetCore 2.1.8

StrongOf.AspNetCore

ASP.NET Core integration for StrongOf types. Includes MVC model binders, Minimal API validation, and OpenAPI schema transformation.

Installation

dotnet add package StrongOf.AspNetCore

MVC Model Binders (StrongOf.AspNetCore.Mvc)

Enables route values, query strings, and form fields to be automatically parsed into strong types.

Available Binders

Setup

Register a custom IModelBinderProvider in your ASP.NET Core startup:

using StrongOf.AspNetCore.Mvc;

// Program.cs
builder.Services.AddControllers(options =>
    options.ModelBinderProviders.Insert(0, new MyBinderProvider()));

// MyBinderProvider.cs
public sealed class MyBinderProvider : IModelBinderProvider
{
    private static readonly IReadOnlyDictionary<Type, Type> s_binders =
        new Dictionary<Type, Type>
        {
            { typeof(UserId),       typeof(StrongGuidBinder<UserId>)   },
            { typeof(EmailAddress), typeof(StrongStringBinder<EmailAddress>) },
        };

    public IModelBinder? GetBinder(ModelBinderProviderContext context)
    {
        if (s_binders.TryGetValue(context.Metadata.ModelType, out Type? binderType))
        {
            return new BinderTypeModelBinder(binderType);
        }
        return null;
    }
}

Custom Binders

Extend StrongOfBinder to add custom parsing logic:

using StrongOf.AspNetCore.Mvc;

public sealed class MyUserIdBinder : StrongOfBinder
{
    public override bool TryHandle(string value, out ModelBindingResult result)
    {
        if (StrongGuid<UserId>.TryParse(value, out UserId? id))
        {
            result = ModelBindingResult.Success(id);
            return true;
        }
        result = ModelBindingResult.Failed();
        return false;
    }
}

Minimal APIs (StrongOf.AspNetCore.MinimalApis)

All strong types implement IParsable<TSelf> and work as route/query parameters in Minimal APIs out of the box.

Use the validation filter to automatically validate IValidatable parameters:

using StrongOf.AspNetCore.MinimalApis;

// Strong types work as route parameters out of the box
app.MapGet("/users/{id}", (UserId id) => Results.Ok(id));

// Register the endpoint filter for automatic validation of IValidatable types
app.MapPost("/users", (EmailAddress email) => Results.Ok(email))
   .WithStrongOfValidation();

OpenAPI Schema Transformer (StrongOf.AspNetCore.OpenApi)

Requires .NET 9.0 or later

Maps strong types to their underlying primitive types in OpenAPI documentation, so API schemas show string (uuid) instead of a complex object for UserId.

using StrongOf.AspNetCore.OpenApi;

builder.Services.AddOpenApi(options =>
{
    options.AddSchemaTransformer<StrongOfSchemaTransformer>();
});

Type Mappings

GitHub

See https://github.com/BenjaminAbt/StrongOf