Loading javascript dynamically based on the http or https protocol

Question

I have a javascript file located in a different server, and I am including the javascript file over http page like

<script type="text/javascript" src="http://www.example.com/scriptfile.js">

or over https page like

<script type="text/javascript" src="https://www.example.com/scriptfile.js">

The problem is, that I have page switching from http to https , for example, if a user is in

http://www.example.com/home (site home URL) and I load the javascript over http , now when the user navigates to another page like https://www.example.com/transaction (site transaction URL), I load the script over https and its working fine. From the mentioned transaction URL if the user hits the https://www.example.com/home (home URL changed to https ), the script which I loaded over http fails because of unsecured content. Any suggestion to handle this is welcomed.

Answer 1

The protocol is optional. If you omit it, the browser will use whatever the document's protocol is. So you can do:

<script type="text/javascript" src="//www.mydomain.com/scriptfile.js">

The correct protocol will be used.

Answer 2

Use a protocol-relative URL for your script:

<script type="text/javascript" src="//www.mydomain.com/scriptfile.js">

This will use the same protocol as the calling page.