ApiModules

ApiModules is a .NET library that enhances Minimal APIs by simplifying route organization and integrating with MediatR and FluentValidation. It also offers automatic transaction handling.

Why ApiModules?

We developed ApiModules while building a fintech platform to address two main issues in our microservices:

1. Excessive boilerplate code, especially in controllers
2. Complex mappings between requests, commands/queries, and responses

By adopting the REPR (Request-Endpoint-Response) pattern and Minimal APIs, ApiModules streamlines development and ensures consistency across our team.

Project Status

ApiModules is currently a work in progress, but it's already being used successfully in production environments in high-stakes scenarios. While we continue to refine and expand the library and its documentation, you can confidently use ApiModules in your projects.

Quick Start

1. Create a new web application:

   dotnet new web --output ExampleApi
   

2. Add the ApiModules package:

   dotnet add package ApiModules --version 1.0.0-beta
   

3. Update your Program.cs:

   using ApiModules;
   
   var builder = WebApplication.CreateBuilder(args);
   builder.Services.AddApiEndpoints<Program>();
   
   var app = builder.Build();
   app.UseApiEndpoints();
   app.Run();

Creating Your First Endpoint

1. Define request and response objects GetForecasts.cs:

   public record GetForecastsRequest([FromRoute] string City) : IApiRequest;
   public record GetWeatherResponse(WeatherForecast[] Forecasts);

2. Create a handler GetForecasts.cs:

   public class GetForecasts : IApiCommand<GetForecastsRequest>
   {
       public async Task<IResult> Handle(GetForecastsRequest request, CancellationToken cancellationToken)
       {
            if (request.City.Equals("Gotham City", StringComparison.OrdinalIgnoreCase))
                return TypeResults.NotFound(); 
           
           // More handler logic to retrieve forecasts
           
           return TypedResults.Ok(new GetWeatherResponse(forecasts));
       }
   }

3. Define an ApiModule to map routes:

   public class ApiModule : BaseApiModule
   {
       public override IEndpointRouteBuilder MapApiModule(IEndpointRouteBuilder endpointRouteBuilder)
       {
           var group = endpointRouteBuilder.MapGroup("/weatherforecasts")
               .WithTags("WeatherForecasts");
   
           group.MapGetCommand<GetForecastsRequest>("/{city}")
               .Produces<GetForecastsResponse>()
               .Produces<NotFound>();
   
           return group;
       }
   }

ApiModules automatically scans for classes implementing BaseApiModule and registers all routes during startup.

Further Examples

To explore implementations of other HTTP verbs and see more usage scenarios, check out our examples in the TestApi directory of our GitHub repository:

ApiModules TestApi Examples

These examples demonstrate how to leverage ApiModules for various HTTP methods and showcase best practices for structuring your API endpoints.