How to do Pen testing / Security testing on Microservices?

Wanted to test microservices for security requirements and did some google and found some good blogs e.g URL: http://ift.tt/2kjOEoZ.

Eg.SQL Injection Vulnerable Dorks. inurl:index.php?id=

How to test if URL don't have any PHP stuff. And check for Vulnerability. I am new in this security testing area. Please help me.
Thank you