transforming all string attributes which are boolean to true booleans - json

Question

I thought this would be simple, perhaps it is but on my jolt learning journey i am once again struggling.
I have some json files (without a schema) which can be up to say 30Mb in size which have many thousands of string attributes at all levels of the document some of which (say 20%) which hold booleans as strings types.
I get that i can write a spec to pick out individual ones and convert them as per (post)[https://stackoverflow.com/questions/64972556/convert-boolean-to-string-for-map-values-in-nifi-jolt]
They technique wont work for me as nesting and levels are very arbitrary and there are simply way to many of them.
so how can i apply the data type transform to any attribute which has a boolean represented as a string ?
for example input
{
"name": "Fred",
"age": 45,
"opentowork" : "true",
"friends" : [
{
"name": "penny",
"closefriend": "false"
},
{
"name": "roger",
"farfriend": "true"
}
]
}
to desired
{
"name": "Fred",
"age": 45,
"opentowork" : true,
"friends" : [
{
"name": "penny",
"closefriend": false
},
{
"name": "roger",
"farfriend": true
}
]
}
I want to pick up attributes opentowork, closefriend and farfriend without explicity defining them int the spec, i also need to leave the values of the other attributes as they are (whatever level they are at).

Answer 1

You can use =toBoolean conversion just a bit separating case within the friends array by using "f*" representation from the else case "*" such as
[
{
"operation": "modify-overwrite-beta",
"spec": {
"*": "=toBoolean",
"f*": {
"*": {
"*": "=toBoolean"
}
}
}
}
]
or some multiple modify specs, without explicitly defining any attribute/array/object, might be added at the number of desired levels such as
[
{
"operation": "modify-overwrite-beta",
"spec": {
"*": "=toBoolean"
}
},
{
"operation": "modify-overwrite-beta",
"spec": {
"*": {
"*": "=toBoolean"
}
}
},
{
"operation": "modify-overwrite-beta",
"spec": {
"*": {
"*": {
"*": "=toBoolean"
}
}
}
}
]