Two spring boot/cloud micro-services based on gradle are created.

Both micro-services are registered in Consul ( HashiCorp )

External micro-service is calling the internal one using Feign with service discovery  provided by Consul.

External micro-service is exposing REST endpoints: 

GET /message 
returns all messages  POST /message 
adds a message body: {"message":"some text"} 
and returns id created for this new message {"id":1}  GET /message/{id} 
returns specific message by id 
{"message":"some text", "id": 1} 
DELETE /message/{id} 
confirms deletion

The internal one is implementing same endpoints as external.