Inject $http into NavbarExtension

Currently I'm developing Kibana 5.6.4 custom plugin to inject a button to discover, now the problem that I have is I want to inject an $http to the run method so that I could make an http request to backend

import { NavBarExtensionsRegistryProvider } from 'ui/registry/navbar_extensions';

function discoverControlProvider() {
 return {
   appName: 'discover',
   key: 'heiho',
   label: 'Heiho',
   run: (elm, prop) => {
       button.disable(); // Disable the button
       $http.get(); // This is what I'm trying to do
        
   }
 }
}

NavBarExtensionsRegistryProvider.register(discoverControlProvider);

Is that possible ? Also is it possible to disable the button upon making http request programmatically ?

I believe you should be able to grab a references to $http by simply passing it into the function (see https://www.w3schools.com/angular/angular_http.asp). Does that not work? And yes you should be able to disable the button.