RED metrics for NSX API

[girikuncoro]

We need to implement RED metrics for call to NSX API

(Request) Rate - the number of requests, per second, you services are serving.
(Request) Errors - the number of failed requests per second.
(Request) Duration - distributions of the amount of time each request takes.

Ref: https://www.weave.works/blog/the-red-method-key-metrics-for-microservices-architecture/