find and modify deeply nested object in javascript array

Question

I have an array of objects that can be of any length and any depth. I need to be able to find an object by its id and then modify that object within the array. Is there an

Answer 1

Here's an example that extensively uses lodash. It enables you to transform a deeply nested value based on its key or its value.

const _ = require("lodash")
const flattenKeys = (obj, path = []) => (!_.isObject(obj) ? { [path.join('.')]: obj } : _.reduce(obj, (cum, next, key) => _.merge(cum, flattenKeys(next, [...path, key])), {}));


const registrations = [{
  key: "123",
  responses:
  {
    category: 'first',
  },
}]


function jsonTransform (json, conditionFn, modifyFn) {

  // transform { responses: { category: 'first' } } to { 'responses.category': 'first' }
  const flattenedKeys = Object.keys(flattenKeys(json));

  // Easily iterate over the flat json
  for(let i = 0; i < flattenedKeys.length; i++) {
    const key = flattenedKeys[i];
    const value = _.get(json, key)

    // Did the condition match the one we passed?
    if(conditionFn(key, value)) {

      // Replace the value to the new one    
      _.set(json, key, modifyFn(key, value)) 
    }
  }

  return json
}

// Let's transform all 'first' values to 'FIRST'
const modifiedCategory = jsonTransform(registrations, (key, value) => value === "first", (key, value) => value = value.toUpperCase())

console.log('modifiedCategory --', modifiedCategory)
// Outputs: modifiedCategory -- [ { key: '123', responses: { category: 'FIRST' } } ]