Unable to map route for robots.txt in asp.net mvc - asp.net-mvc

Question

I am developing an asp.net mvc application. I am creating robots.txt for my application to prevent from bots because my current site is getting many robot requests. So I found this link, Robots.txt file in MVC.NET 4 to create robots.txt. But I when I access my application like this entering url, "www.domain.com/robots.txt", it is always returning 404 page.
This is my action method in HomeController
public ActionResult Robots()
{
Response.ContentType = "text/plain";
return View();
}
This is my robots view
#{
Layout = null;
}
User-agent:*
Disallow:/
I configured route for robots.txt like this in RouteConfig
public static void RegisterRoutes(RouteCollection routes)
{
routes.IgnoreRoute("{resource}.axd/{*pathInfo}");
//routes.MapMvcAttributeRoutes();
routes.MapRoute(
"Robots.txt",
"robots.txt",
new { controller = "Home", action = "Robots" },
new string[] { "AyarDirectory.Web.Controllers" }
);
//other routes
}
But when I access this url, "www.domain.com/robots.txt", it is always returning 404 page. How can I add robots.txt correctly to my application?

Answer 1

Creating a route ending with a file extension is not allowed by default in ASP.NET MVC. To get around this security restriction, you need to add the following to the Web.config file:
<?xml version="1.0" encoding="utf-8"?>
<configuration>
<!-- ...Omitted -->
<system.webServer>
<!-- ...Omitted -->
<handlers>
<!-- ...Omitted -->
<add name="RobotsText"
path="robots.txt"
verb="GET"
type="System.Web.Handlers.TransferRequestHandler"
preCondition="integratedMode,runtimeVersionv4.0" />
</handlers>
</system.webServer>
</configuration>

Answer 2

In Asp.net Core you can simply add your robots.txt file to the wwwroot directory.

Answer 3

Would say same thing as above you need to change the web.config to allow the route with .txt to work. I had same issue with a project I was working on and I got it to work.
However if you using a view for the output of the robots without a model you might as well keep a static robots.txt as it will give you no advantage. Another way is to output the text direct from the action using a string builder.

Answer 4

Nkosi's System.Web.Handlers.TransferRequestHandler approach in web.config approach did not work for me due to the environment I was working in, resulting in 500 errors.
An alternative of using a web.config url rewrite rule worked for me instead:
<rewrite>
<rules>
<rule name="Dynamic robots.txt" stopProcessing="true">
<match url="robots.txt" />
<action type="Rewrite" url="/DynamicFiles/RobotsTxt" />
</rule>
</rules>
</rewrite>