I just installed simple-json plugin and it appears as a potential data source.
Using Postman I was able to check request and response based on examples from https://github.com/grafana/simple-json-datasource.
However, there is an error in the request example as:
This seems to be due to missing “” for refId as when it is manually converted to “refId” it works at Postman.
I really appreciate to have some help on this.