Recursively transform JSON using jolt-CodePudding

I am trying to transform a JSON into another JSON using JOLT.

My source JSON has the following format (the number of levels of child modules is not known):

Input

{
  "modules": [
    {
      "id": "1",
      "modules": [
        {
          "id": "1.1",
          "modules": []
        },
        {
          "id": "1.2",
          "modules": [
            {
              "id": "1.2.1",
              "modules": []
            }
          ]
        }
      ]
    },
    {
      "id": "2",
      "modules": [
        {
          "id": "2.1",
          "modules": []
        }
      ]
    }
  ]
}

My JOLT transformation spec looks like this:

Spec:

The output I get is:

[
  {
    "operation": "shift",
    "spec": {
      "modules": {
        "*": {
          "id": "new_modules[&1].id"
        }
      }
    }
  }
]

Desired Output:

{
  "new_modules": [
    {
      "id": "1"
    },
    {
      "id": "1.1"
    },
    {
      "id": "1.2"
    },
    {
      "id": "1.2.1"
    },
    {
      "id": "2"
    },
    {
      "id": "2.1"
    }
  ]
}

I am adding some unrelated text below as StackOverflow complains that my question is mostly code and that I must add more details. Kindly let me know if I am missing details.

CodePudding user response：

You can use this spec:

[
  {
    "operation": "shift",
    "spec": {
      "modules": {
        "*": {
          "id": "new_modules[].&",
          "modules": {
            "*": {
              "id": "new_modules[].&",
              "modules": {
                "*": {
                  "id": "new_modules[].&",
                  "modules": {
                    "id": "new_modules[].&"
                  }
                }
              }
            }
          }
        }
      }
    }
  }
]

You can't have infinite levels in the jolt. But you can increase your levels in the above code.

CodePudding user response：

You can use such a shift transformation spec

[
  {
    "operation": "shift",
    "spec": {
      "modules": {
        "*": {
          "id": "&2[&1].x&1.&",// &2 represents going two levels up and grab the key value "modules", [&1] represents going one level up the tree to reach the level of the indexes of the "module" array and generating values in arraywise manner
          "mod*": {// even using "*" is enough instead of "mod*" as an else case if the style is the same as in the current sample for all JSON values
            "*": {
              "id": "&4[&3].y&1.&",
              "mod*": {
                "*": {
                  "id": "&6[&5].z&1.&"
                }
              }
            }
          }
        }
      }
    }
  },
  {
    "operation": "shift",
    "spec": {
      "*": {
        "*": {
          "*": "new_&2[]" // &2 replicates the literal "modules"
        }
      }
    }
  }
]

considering a JSON value with a 3 level of deepness at most.