Follow the given steps to implement this recipe:

1. Open the main.rs file in the src directory in your preferred text editor.
2. Write the code header with the relevant information:

        //-- #########################
        //-- Task: Json handling in nickel
        //-- Author: Vigneshwer.D
        //-- Version: 1.0.0
        //-- Date: 20 April 17
        //-- #########################

3. Import the installed nickel and rustc_serialize crates by using the extern keyword:

        extern crate rustc_serialize;
        #[macro_use] extern crate nickel;

        use nickel::{Nickel, HttpRouter, JsonBody};

4. Define a custom Struct type named Person:

        #[derive(RustcDecodable, RustcEncodable)]
        struct Person {
          firstname: String,
          lastname: String,
        }

5. Define the main function, where we declare the server instance:

        fn main() {
          let mut server = Nickel::new();

          server.post("/a/post/request", middleware! {
          |request,
          response|
          let person = request.json_as::<Person>().unwrap();
          format!("Hello {} {}", person.firstname,
          person.lastname)});

          server.listen("127.0.0.1:6767");
        }

6. Save the file and start the server with the following command from the root directory of the project:

      cargo run

We will get the following output on the successful execution of our code in the terminal:

Open your terminal and enter the following command to hit the endpoint with curl:

        curl -H "Content-Type: application/json" -X POST -d
        '{"firstname":"Vigneshwer","lastname":"Dhinakaran"}'
        http://127.0.0.1:6767/a/post/request

On successfully hitting the endpoint with the curl command, we will get the following response (highlighted) in the output: