I have a JSON structure that looks like:

{
  "A": {
    "NestedArray": [
      {
        "AlreadyHere2": "x"
      },
      {
        "AlreadyHere2": "x"
      },
      {
        "AlreadyHere2": "x"
      }
    ]
  }
}

I need to add new Json fields with the same CONSTANT value to specific parts of the existing json document so it becomes:

{
  "A": {
    "A_1": "CONSTANT",
    "A_2": "CONSTANT",
    "NestedArray": [
      {
        "AlreadyHere2": "x",
        "arrayValue": "CONSTANT"
      },
      {
        "AlreadyHere2": "x",
        "arrayValue": "CONSTANT"
      },
      {
        "AlreadyHere2": "x",
        "arrayValue": "CONSTANT"
      }
    ]
  }
}

Note: in the case for arrays, add CONSTANT to each element.

I have a list of the specific json paths available to use as a “traversal guide” that could have more values added to in the future so my implementation can’t be tailored to the existing json structure. i.e.:

val list = List("A.A_1", "A.A_2", "A.NestedArray.arrayValue")

I see that there’s this for recursively modifying JSON: https://circe.github.io/circe/optics.html#recursively-modifying-json

but I am not sure how I can handle adding to specific new fields and in arrays. Any help would be greatly appreciated, thank you!