Zend certified PHP/Magento developer

How to call Magento 2 Oauth 1.0 API for services without Callback & Identity URL?

We cannot integrate with 3rd Systems like ERP with Callback URL or Identity URL in some cases.

The git repository available can be used to call Oauth request from PHP https://github.com/daviddesberg/PHPoAuthLib

But in case of calling Magento2 Oauth is tricky.

Need PHP Script to demonstrate Oauth call with signature generation process.