Apply .NET Core MVC InputFormatter to controller

Question

I'm pretty new to .NET Core. I'm trying to set up a little MVC application. Where i implemented a controller with a defined Route.

[Route("api/ota")]
public class OTAController : ControllerBase
{
    [HttpPost]
    public async Task<ContentResult> EndPoint([FromBody] object otaHotelRatePlanNotifRQ)
    {
        Console.WriteLine("Something is posted");
        ...

for this controller i implemented a custom inputformatter and registered it in the Startup.cs works fine so far.

        services.AddMvc(options => {
            options.InputFormatters.Insert(0, new RawRequestBodyInputFormatter());
        }).SetCompatibilityVersion(CompatibilityVersion.Version_2_1)

But now this inputformatter is applied for any controller and specified route. Is there any way to apply the formatter just for a specified controller/route.

Answer 1

Yes this can be in the Startup.cs by adding a new route in the config method, you should have something like this by default you need to add a new one for the controller that you want:

app.UseMvc(routes =>
            {
                routes.MapRoute(
                    name: "default",
                    template: "{controller=Home}/{action=Index}/{id?}");
            });

Note: The order matters.

Answer 2

add your inputformatter as the first formatter InputFormatters.Insert(0,new StringRawRequestBodyFormatter()) then in this formatter in CanRead method check if the parameter that is being bound has a custom attribute you specify alongside FromBody

 public override Boolean CanRead(InputFormatterContext context)
    {
        if (context == null) 
            throw new ArgumentNullException(nameof(context));
        
        var contentType = context.HttpContext.Request.ContentType;
        if (supportedMimes.Contains(contentType) && 
            context.Metadata is DefaultModelMetadata mt &&
            mt.Attributes.ParameterAttributes.Any(a=>a.GetType().Equals(typeof(RawJsonAttribute))))
            return true;
        else
            return false;
    }

Controller action:public IActionResult BeginExportToFile([RawJson,FromBody] string expSvcConfigJsonStr)

So in simple terms this formatter will only be used for the supported mimes and for parameters that have a custom attribute. Hope it helps.