Flatten JS Object Keys

flatten.js

function flatten(obj) {
  const result = {};
  for (const key of Object.keys(obj)) {
    if (typeof obj[key] === 'object') {
      const nested = flatten(obj[key]);
      for (const nestedKey of Object.keys(nested)) {
        result[`${key}.${nestedKey}`] = nested[nestedKey];
      }
    } else {
      result[key] = obj[key];
    }
  }
  return result;
}

https://stackoverflow.com/a/74769002/882371

Example Input:

{
  "first_name": "validations.required",
  "no_middle_name": "validations.required",
  "last_name": "validations.required",
  "dob": "validations.required",
  "citizenship": "validations.required",
  "citizenship_identity": {
    "name": "validations.required",
    "value": "validations.required"
  },
  "address": [
    {
      "country_code": "validations.required",
      "street": "validations.required",
      "city": "validations.required",
      "state": "validations.required",
      "zipcode": "validations.required",
      "start_date": "validations.required",
      "end_date": "validations.required"
    },
    {
      "country_code": "validations.required",
      "street": "validations.required",
      "city": "validations.required",
      "state": "validations.required",
      "zipcode": "validations.required",
      "start_date": "validations.required",
      "end_date": "validations.required"
    }
  ]
}

Example Output:

const flattenedOutput = flatten(inputObj);

{
  "first_name": "validations.required",
  "no_middle_name": "validations.required",
  "last_name": "validations.required",
  "dob": "validations.required",
  "citizenship": "validations.required",
  "citizenship_identity.name": "validations.required",
  "citizenship_identity.value": "validations.required",
  "address.0.country_code": "validations.required",
  "address.0.street": "validations.required",
  "address.0.city": "validations.required",
  "address.0.state": "validations.required",
  "address.0.zipcode": "validations.required",
  "address.0.start_date": "validations.required",
  "address.0.end_date": "validations.required",
  "address.1.country_code": "validations.required",
  "address.1.street": "validations.required",
  "address.1.city": "validations.required",
  "address.1.state": "validations.required",
  "address.1.zipcode": "validations.required",
  "address.1.start_date": "validations.required",
  "address.1.end_date": "validations.required"
}