Can I populate the json templater automatically using attribute/values present in my source?

To populate in an automated way the json templater what I would to do is to add the string stored in 2 attributes that I created in the table of my source.

The first one is to create the list of attribute name and the second one to run the command in Json templater to add the value of the same attributes present in the source. ( see picture)

something like:

{

   "id":fme:get-attribute("id"),

   "@ns:com:here:customer:$(CustomerName)": {

                   "objectidOriginal": fme:get-attribute("objectidOriginal"),

                   "toaddr_l": fme:get-attribute("toaddr_l"),

                   "toaddr_r": fme:get-attribute("toaddr_r"),

                   ..............................

                   ..............................

                   ..............................

                   "filegdb_type": fme:get-attribute("filegdb_type")

}

I created this ROOT:

{

   "id":fme:get-attribute("id"),

   "@ns:com:here:customer:$(CustomerName)": 

                   [fme:process-features("ATTRIBUTENAME")]

 }

But I have problem to add the rigth sintax in the sub-template.

I tested something like that and others string:

{

   fme:get-attribute("attributename"):fme:get-attribute("CustomAttributes")

}

but doesn't work.

first of all, I am not sure if it is possible.

But if yes, do you have some suggestion?

Thanks

Max