HTTP Wrapper GOLANG and ECHO FRAMEWORK

Question

I am confused in handling HTTP request as wrapper using GOLANG and ECHO FRAMEWORK to build as API service.

Firstly, I have a communication between client and server like below:

This communication is very easy. Secondly,

Step 1: I want to use response from SSO server (parse JWT token ---> get user information)

Step 2: Use user information from response and query database.

Step 3: Response data to client

I show this communication below:

I am beginner in Golang.