Get and verify paths in a nested object - util functions #2

Yesterday I shared with you a utility function to recurrently loop an object in JS, one of the features it has, is that you can get an array with a path to the nested object that is currently being looped. However, when working with nested objects, you may want to retrieve or verify data from a specific path at any given moment, that's what today's utility functions do.

• getDataFromObj(obj, path): retrieve data from a given path in an object
• isValidObjPath(obj, path): verify if a given path exists in an object

getDataFromObj(obj, path)

Feel free to copy and paste this code

/**
 * Retrieves data from an object on a given path
 * @param {Object} obj the object to get the data from
 * @param {string[]} path an array of strings containing the keys of the object to look at
 * @returns {*} the retrieved data or a Reference Error if not found
 */

function getDataFromObj(obj, path){
  // Validate arguments
  if(getType(obj) != "object"){
    throw TypeError("The `obj` argument is not an object");
  }
  if(getType(path) != "array"){
    throw TypeError("The `path` argument is not an array");
  }

  // Get the data or a ReferenceError if not found
  const data = (()=>{
    let currentData = obj;

    for(let i = 0; i < path.length; i +=1 ){
      if(Object.keys(currentData).includes(path[i])){
        currentData = currentData[path[i]];
        continue;
      } else{
        currentData = ReferenceError("The object path is not defined");
        break;
      }
    }
    return currentData;
  })();

  return data;
}

/**
 * A method to detect data types more accurately
 * Credits: Chris Ferdinandi, https://gomakethings.com/
 * @param {*} data the data to be verified
 * @returns {String} the data type
 */
function getType(data){
  return Object.prototype.toString.call(data).toLowerCase().slice(8, -1)
}

/**
 * License: MIT, https://opensource.org/license/mit
 * Copyright (c) 2024 Rodrigo Isaias Calix
 */

Usage:

You must pass 2 arguments:
obj: The object from where you want to retrieve the data
path: An array indicating the sequence to follow

If the path exists it will return the value (even if the value is undefined), if the path doesn't exist it will return a ReferenceError object, it doesn't throw an error, just returns the error object.

const products = {
  computers: {
    laptop: 20,
    desktop: 15,
    mini: 8
  },
  cameras: 20,
  externalDevices: {
    keyboard: {
      usb: 45,
      bluetooth: 25,
      other: undefined
    }
  }
}

// This would log 25
console.log(getDataFromObj(products, ["externalDevices", "keyboard", "bluetooth"]))

// this would return a ReferenceError object (not a throw, just the error object)
console.log(getDataFromObj(products, ["externalDevices", "mouse"]))

// this would return `undefined`
console.log(getDataFromObj(products, ["externalDevices", "keyboard", "other"]))

isValidObjPath(obj, path)

The utility code:

/**
 * verify if an object has an specific path
 * @param {Object} obj the object to be verified
 * @param {string[]} path an array of strings containing the keys of the object to look at
 * @returns {Boolean} `true` if found, otherwise `false`
 */
function isValidObjPath(obj, path){
  // Validate arguments
  if(getType(obj) != "object"){
    throw TypeError("The `obj` argument is not an object");
  }
  if(getType(path) != "array"){
      throw TypeError("The `path` argument is not an array");
  }

  // shallow copy of the object to be verified
  let currentData = obj;

  // Verify the path
  for(let i = 0; i < path.length; i +=1 ){
    if(Object.keys(currentData).includes(path[i])){
      currentData = currentData[path[i]];
      continue;
    } else{
      return false;
    }
  }

  return true;
}

/**
 * A method to detect data types more accurately
 * Credits: Chris Ferdinandi, https://gomakethings.com/
 * @param {*} data the data to be verified
 * @returns {String} the data type
 */
function getType(data){
  return Object.prototype.toString.call(data).toLowerCase().slice(8, -1)
}

/**
 * License: MIT, https://opensource.org/license/mit
 * Copyright (c) 2024 Rodrigo Isaias Calix
 */

Usage:

You must pass 2 arguments:
obj: The object that you want to verify if a path exists
path: An array indicating the sequence to follow

If the path you are searching exists, it will return true, otherwise it will return false

const products = {
  computers: {
    laptop: 20,
    desktop: 15,
    mini: 8
  },
  cameras: 20,
  externalDevices: {
    keyboard: {
      usb: 45,
      bluetooth: 25,
      other: undefined
    }
  }
}

// This would log true
console.log(isValidObjPath(products, ["externalDevices", "keyboard", "bluetooth"]))

// this would log false
console.log(isValidObjPath(products, ["externalDevices", "mouse"]))

// this would log true
console.log(isValidObjPath(products, ["externalDevices", "keyboard", "other"]))

Why an array as the path instead of a string with slashes or dots? (e.g. "computers.laptop")

Because object property names can also be a string with a large range set of characters, which includes dots, so, for example, "computers.laptop": {[...]} would be a valid object, an array would allow more flexibility and accuracy.

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