good way to return all deeply object's nested keys with values in javascript

Question

I need to access and return all deeply nested key's in an object and return them based on a key.

For example I have

const chatSettings = {
  name: {
    questions: {
      question: 'What\'s your name?',
      fields: [
        {
          field: 'textinput',
          type: 'text',
          key: 'firstname',
          label: 'First name'
        },
        {
          field: 'textinput',
          type: 'text',
          key: 'lastname',
          label: 'Last name'
        },
      ]
    }
  },
  email: {
    questions: {
      question: 'Okay. {{username}}. Now type your email addess',
      fields: [
        {
          field: 'textinput',
          type: 'email',
          key: 'email',
          label: 'Email'
        }
      ]
    }
  }
}

And I need something like, getAllValuesForKey(chatSettings, 'key') , which would return ['firstname', 'lastname', 'email']

Any ideas how to do it in a performant way while as well taking into account that some of these objects might not even have this key?

Answer 1

You could create recursive function with reduce method and return array as a result.

 const data = {"name":{"questions":{"question":"What's your name?","fields":[{"field":"textinput","type":"text","key":"firstname","label":"First name"},{"field":"textinput","type":"text","key":"lastname","label":"Last name"}]}},"email":{"questions":{"question":"Okay. {{username}}. Now type your email addess","fields":[{"field":"textinput","type":"email","key":"email","label":"Email"}]}}} function find_deep(data, key) { return Object.keys(data).reduce((r, e) => { if (typeof data[e] == 'object') r.push(...find_deep(data[e], key)) if (key == e) r.push(data[e]) return r }, []) } console.log(find_deep(data, 'key')) 

Answer 2

You could use a recursive function with a type check and reduce the object.

 function getValues(object, key) { return object && typeof object === 'object' ? Object .entries(object) .reduce((r, [k, v]) => r.concat(k === key ? v : getValues(v, key)), []) : []; } var chatSettings = { name: { questions: { question: 'What\\'s your name?', fields: [{ field: 'textinput', type: 'text', key: 'firstname', label: 'First name' }, { field: 'textinput', type: 'text', key: 'lastname', label: 'Last name' },] } }, email: { questions: { question: 'Okay. {{username}}. Now type your email addess', fields: [{ field: 'textinput', type: 'email', key: 'email', label: 'Email' }] } } }, values = getValues(chatSettings, 'key'); console.log(values); 

Answer 3

 const chatSettings = { name: { questions: { question: 'What\\'s your name?', fields: [ { field: 'textinput', type: 'text', key: 'firstname', label: 'First name' }, { field: 'textinput', type: 'text', key: 'lastname', label: 'Last name' }, ] } }, email: { questions: { question: 'Okay. {{username}}. Now type your email addess', fields: [ { field: 'textinput', type: 'email', key: 'email', label: 'Email' } ] } } } function getAllValuesByKey(obj, key) { let values = [] if(Array.isArray(obj)) { obj.forEach(o => { let value = getAllValuesByKey(o, key) if(value && value.length > 0) { values = values.concat(value) } }) } else if(typeof obj === 'object') { Object.keys(obj).forEach(k => { if(k == key) { values.push(obj[k]) } if(Array.isArray(obj[k]) || typeof obj[k] == 'object') { let value = getAllValuesByKey(obj[k], key) if(value && value.length > 0) { values = values.concat(value) } } }) } return values } console.log(getAllValuesByKey(chatSettings, 'key'))