How to recursively process JSON data and return processed JSON from a function?

Question

I have JSON data with nested objects. I want to remove the "id" from this structure and return the changed JSON from this function. I tried to do this recursively below, but could not return the modified JSON.

var jsonStr = 
{"_id":"7r0c0342e",
"user":"myuser",
"project":"abcd",
"info":{"DOMAIN":{"Department":{"profile":[{"workex":8,"name":"alex","id":82838},
{"workex":8,"name":"smith","id":84838} ]}}} };


processJSON(jsonStr);

function processJSON(jsondata) {
    for (var i in jsondata) {
        var row = jsondata[i];           
        if(typeof row == "object") {
            processJSON(row);              
        } else if(typeof row == 'number') {
            if(i == 'id') {
                delete jsondata[i];                    
            } else {                
                continue;
            }
        } else {
            continue;
        }              
      }   
}

console.log(jsonStr);

How can I return the rest of the JSON from processJSON () and hold it in a variable? Secondly, is this the right way to do this recursively?

Thank.

Answer 1

var jsonStr =
    {
        "_id": "7r0c0342e",
        "user": "myuser",
        "project": "data_mining",
        "info": {
            "DOMAIN": {
                "Department": {
                    "profile": [{"workex": 8, "name": "alex", "id": 82838},
                        {"workex": 8, "name": "smith", "id": 84838}]
                }
            }
        }
    };
let modifedJson = JSON.parse(JSON.stringify(jsonStr));

parseJson = function (json) {
    for (let key in json) {
        if (key === 'id') {
            delete json[key];
        }
        else if (typeof json[key] === 'object') {
            parseJson(json[key])
        }

    }
}
parseJson(modifedJson)
console.log('modified',modifedJson)
console.log('original',jsonStr)

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Answer 2

With your approach, you mutate the original object, so to some extent you don't need to return anything.

, . , . Object.assign:

var jsonStr = {"_id":"7r0c0342e", "user":"myuser", "project":"data_mining", "info":{"DOMAIN":{"Department":{"profile":[{"workex":8,"name":"alex","id":82838}, {"workex":8,"name":"smith","id":84838} ]}}} };

console.log(processJSON(jsonStr));

function processJSON(jsondata) {
  var output = Object.assign({}, jsondata)

  for (var i in output) {
    var row = output[i];
    if (typeof row == "object") {
      output[i] = processJSON(row);
    } else if (typeof row == 'number') {
      if (i == 'id') {
        delete output[i];
      } else {
        continue;
      }
    } else {
      continue;
    }
  }

  return output;
}

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