Counting nested objects

Hello everyone,

I am using Grafana 7 with Elasticsearch DB. And I want to count the number of nested objects inside one of the field coming from the Raw data.
The field is called rxInfo and the object inside it looks something like this…
[object Object],[object Object],[object Object],[object Object]

If you observe carefully, it has 4 objects inside an array, I just want to have this count, that is 4.

Any kind of help would be greatly appreciated. Thanks in advance.