M2 Note: Classes for building rest client in your extension
This is about using Magento 2 internal classes useful for building restapi client in your magento extension.
Oauth class will help you deal with REST authorization. Interesting function is `buildAuthorizationHeader` . Of course you should inject \Magento\Framework\Oauth\OauthInterface in your code instead of the class.
For building valid json bodies.
If you want to convert an object like order to array use.