[SOLVED] How to use functions of java script library which is called asynchronously by my web page?

How to use functions of java script library which is called asynchronously by my web page?

1. My local js file sdk.js is

    (function(sdkUrl,b,flag)
    {
        if (window[b])
            return;
        if (!window.JSON)
            return;
        let url = sdkUrl;
        let h = /Chrome\/(\d+)/.exec(navigator.userAgent);
        h && Number(h[1]) >= 55 && "assign" in Object && "findIndex" in [] && (url += "");
        let js = document.createElement("script");
        js.src = url;
        js.async = !0;
        flag && (js.crossOrigin = "anonymous");
        let i = document.getElementsByTagName("script")[0];
        i.parentNode && i.parentNode.insertBefore(js, i)
    })('http:\/\/phoenix.loc\/sdk\/v1\/gen.js','UB',true);

2. remote js which is being called asynchronously is ub-sdk.js

(function(global)
{
    'use strict';
    var UB = {
        firstName: "John",
        lastName : "Doe",
        id       : 5566,
        fullName : function()
        {
            return this.firstName + " " + this.lastName;
        }
    };
    if (typeof module != 'undefined' && module.exports)
    {
        module.exports = UB;
    }
    else if ( typeof define === "function" && define.amd )
    {
        define( "UB", [], function()
        {
            return UB;
        });
    }
    else
    {
        global.UB = UB;
    }
}(windows));

index.html is like

<html>
<head>
    <title>JS SDK Demo</title>
</head>
<body>
<script src="sdk.js"></script>
<script type="text/javascript">
    console.log(UB.fullName());
</script>
</body>
</html>

I am not able to access functions and objects defined in us-sdk.js. I am using native java script code running under Apache server. Let me know where I am doing it wrong?

Solution

Add an eventlistener to the included script's load-event:

(function(sdkUrl, b, flag) {
  if (window[b])
    return;
  if (!window.JSON)
    return;
  let url = sdkUrl;
  let h = /Chrome\/(\d+)/.exec(navigator.userAgent);
  h && Number(h[1]) >= 55 && "assign" in Object && "findIndex" in [] && (url += "");
  let js = document.createElement("script");
  js.src = url;
  js.async = !0;

  //
  // Listen here:
  //
  js.addEventListener('load', function() {
    console.log($)
  });

  flag && (js.crossOrigin = "anonymous");
  let i = document.getElementsByTagName("script")[0];
  i.parentNode && i.parentNode.insertBefore(js, i)
})('https://code.jquery.com/jquery-3.5.1.slim.min.js', 'UB', true);