List Paths to All Deeply Nested Keys in JavaScript Objects, Recursively

The getKeyPaths function below can be used to get a list of paths within a deeply nested JavaScript or JSON object with a certain key (property).

function getKeyPaths(obj, key, currentPath = '', result = []) {
  if (typeof obj !== 'object' || obj === null) {
    return result;
  }

  for (const property in obj) {
    if (obj.hasOwnProperty(property)) {
      const newPath = currentPath === '' ? property : `${currentPath}.${property}`;

      if (Array.isArray(obj[property])) {
        obj[property].forEach((item, index) => {
          getKeyPaths(item, key, `${newPath}[${index}]`, result);
        });
      } else {
        getKeyPaths(obj[property], key, newPath, result);
      }

      if (property === key) {
        result.push(newPath);
      }
    }
  }

  return result;
}

Example Usage

const data = {
  results: {
    characters: [
      {
        name: 'newman'
      },
      {
        name: 'jerry'
      }
    ]
  },
  platform: {
    nintendo: {
      systems: [
        {
          name: 'Switch'
        },
        {
          name: 'Wii'
        }
      ]
    }
  }
};

const key = 'name';
const accessPaths = getKeyPaths(data, key);

console.log(accessPaths);

// Result:
// [
//   "results.characters[0].name",
//   "results.characters[1].name",
//   "platform.nintendo.systems[0].name",
//   "platform.nintendo.systems[1].name"
// ]

You can then copy and paste any of these paths into your code project as needed to access the keys you need.