Request Binding

Route and query parameters

For GET and DELETE, TRequest is bound from route values and the query string rather than the request body. Annotate properties with [FromRoute] or [FromQuery] to clarify the binding source.

public class GetUserRequest
{
    [FromRoute]
    public required int Id { get; init; }
}

public class GetUserResponse
{
    public required int Id { get; init; }
    public required string Name { get; init; }
}

public class GetUserEndpoint : IEndpoint<GetUserRequest, Response<GetUserResponse>>
{
    public void Configure(IEndpointConfiguration config)
    {
        config.Get("/users/{id}")
            .Tags("Users")
            .Summary("Get a user by ID");
    }

    public async Task<Response<GetUserResponse>> HandleAsync(
        GetUserRequest request,
        CancellationToken cancel)
    {
        var user = await _repository.FindByIdAsync(request.Id, cancel);

        if (user is null)
        {
            return new Response<GetUserResponse>
            {
                StatusCode = HttpStatusCode.NotFound,
                Body       = new GetUserResponse { Id = 0, Name = string.Empty },
            };
        }

        return new Response<GetUserResponse>
        {
            Body = new GetUserResponse { Id = user.Id, Name = user.Name },
        };
    }
}

Custom binding with BindAsync

For custom binding (e.g. multipart/form-data), implement the Minimal API BindAsync convention on the request type. AxisEndpoints detects it automatically:

public class UploadRequest
{
    public required IFormFile File { get; init; }

    public static async ValueTask<UploadRequest> BindAsync(HttpContext context)
    {
        var form = await context.Request.ReadFormAsync();
        var file = form.Files["file"] ?? throw new BadHttpRequestException("'file' field is required.");
        return new UploadRequest { File = file };
    }
}

For CSV-specific binding, see the CSV Import guide.