Minimal API

Video

https://codewithmukesh.com/blog/minimal-apis-aspnet-core/

What Are Minimal APIs

When to use what

Benefit

• Complex types are automatically bound from the request body, using System.Text.Json
  • No need of using [FromBody]
• Services registered in the DI container are automatically injected:

Route Handlers

Route handlers are the core of Minimal APIs. They define what happens when a request hits a specific URL. ASP.NET Core provides methods for all HTTP verbs:

• MapGet() - Handle GET requests
• MapPost() - Handle POST requests
• MapPut() - Handle PUT requests
• MapDelete() - Handle DELETE requests
• MapPatch() - Handle PATCH requests

Parameter Biniding

Route Parameter

Route parameters are extracted from the URL path:

app.MapGet("/products/{id:int}", (int id) => /* id comes from URL */);

app.MapGet("/categories/{name}/products", (string name) => /* name from URL */);

Query Parameter

Parameters not in the route are bound from the query string:

app.MapGet("/products", (string? category, decimal? minPrice, int page = 1, int pageSize = 10) =>
{
    var query = products.AsEnumerable();

    if (!string.IsNullOrEmpty(category))
        query = query.Where(p => p.Category == category);

    if (minPrice.HasValue)
        query = query.Where(p => p.Price >= minPrice);

    return query.Skip((page - 1) * pageSize).Take(pageSize);
});

RouteBuilder

As your API grows, having all endpoints in Program.cs becomes unmanageable. Route groups help organize related endpoints and apply common configurations.

• This pattern keeps related endpoints together and ensures consistent URL prefixes without repetition.
• Route groups can apply common configurations to all child endpoints:

var apiGroup = app.MapGroup("/api/v1")
    .RequireAuthorization();

var productsGroup = apiGroup.MapGroup("/products")
    .WithTags("Products");

var categoriesGroup = apiGroup.MapGroup("/categories")
    .WithTags("Categories");