Async JS/Node - Promises Always Async example

example.js

var http = require('special-http')
 
function getData(endpoint, callback) {
  var promise = new Promise(function(resolver, rejector) {
    if(cache[endpoint]) {
      return resolver(cache[endpoint])
    }
  
    http.get(endpoint).then(function(data) {
      resolver(data)
    }, function(err) {
      rejector(err)
    })
  })
  
  return promise
}