How to use the traverson.registerMediaType function in traverson

after(function() {
    if (isNodeJs() && testServer) {
      testServer.stop();
    }
    // de-register HAL plug-in to leave Traverson in a clean state for other
    // tests
    traverson.registerMediaType(JsonHalAdapter.mediaType, null);
  });

after(function() {
    // de-register HAL plug-in to leave Traverson in a clean state for other
    // tests
    traverson.registerMediaType(JsonHalAdapter.mediaType, null);
  });

after(function() {
    // de-register HAL plug-in to leave Traverson in a clean state for other
    // tests
    traverson.registerMediaType(JsonHalAdapter.mediaType, null);
  });

after(function() {
    traverson.registerMediaType(JsonHalAdapter.mediaType, null);
  });

before(function() {
    traverson.registerMediaType(JsonHalAdapter.mediaType, JsonHalAdapter);
  });

before(function() {
    traverson.registerMediaType(JsonHalAdapter.mediaType, JsonHalAdapter);
    api = traverson.from(rootUri).jsonHal();
  });

before(function() {
    if (isNodeJs()) {
      testServer = require('traverson-test-server');
      testServer.start();
    }
    traverson.registerMediaType(JsonHalAdapter.mediaType, JsonHalAdapter);
 });

var config =  require("../config.js"),
    rootUri = config.rootUri,
    prefix = config.prefix,
    JsonHalAdapter = require("traverson-hal"),
    traverson = require("traverson"),
    api;

traverson.registerMediaType(JsonHalAdapter.mediaType,
    JsonHalAdapter);

api = traverson.from(rootUri);

module.exports = {
    getRootHal: function (callback) {
        api.jsonHal()
            .follow(prefix + "ads")
            .getUri(function (err, uri) {
                if (err) {
                    console.log(err);
                    return;
                }
                callback(uri);
            });
    },

var $ = require("jquery");
var Backbone = require("backbone");
var Backform = require("backform");
var JsonHalAdapter = require("traverson-hal");
require("backbone-relational");
require("backbone-relational-hal");

var traverson = require("traverson");

traverson.registerMediaType(JsonHalAdapter.mediaType,
    JsonHalAdapter);

var rootUri = '/',
    api = traverson.from(rootUri),
    fields = [{
        name: "amount",
        label: "Количество:",
        control: "input",
        type: "number"
    }, {
        name: "currency",
        label: "Тип валюты:",
        control: "select"
    }, {
        name: "rate",
        label: "Курс:",

var Backbone = require("backbone");
require("backbone-relational");
require("backbone-relational-hal");

var rootUri = "/",
    prefix = "currency-black-market:",
    JsonHalAdapter = require("traverson-hal"),
    traverson = require("traverson");


traverson.registerMediaType(JsonHalAdapter.mediaType,
    JsonHalAdapter);

var api = traverson.from(rootUri);
var resource = require("../../controller/resource.js");

var AdsModel = Backbone.RelationalHalResource.extend({
    initialize: function () {
        resource.getRootHal(function (halUrl) {
            this.halUrl = halUrl;
            this.fetch();
        }.bind(this));
    }
});

module.exports = AdsModel;