CaseChange (object deep camelizer/underscorer)

CaseChange.js

import _ from 'lodash'

const CaseChange = {
  camelizeKey: _.memoize(_.camelCase),
  underscoreKey: _.memoize(_.snakeCase),

  convertToCamelcase(object) {
    return deepMapKeys(object, CaseChange.camelizeKey)
  },

  convertToUnderscore(object) {
    return deepMapKeys(object, CaseChange.underscoreKey)
  },
  
  camelizeKeysInPlace(object) {
    deepMutateMapKeys(object, CaseChange.camelizeKey)
  },

  underscoreKeysInPlace(object) {
    deepMutateMapKeys(object, CaseChange.underscoreKey)
  }
}

function deepMapKeys(obj, keyMapper) {
  if (_.isArray(obj)) {
    return obj.map(v => deepMapKeys(v, keyMapper))
  }
  else if (_.isObject(obj)) {
    return _.transform(obj, (a, v, k) => { a[keyMapper(k)] = deepMapKeys(v, keyMapper) }, {})
  }
  else {
    return obj
  }
}

function deepMutateMapKeys(object, fn) {
  if (_.isArray(object)) {
    return object.map((item) => deepMutateMapKeys(item, fn))
  }
  else if (_.isObject(object)) {
    Object.keys(object).forEach((key) => {
      const value = object[key]
      delete object[key]
      object[fn(key)] = deepMutateMapKeys(value, fn)
    })
  }
  return object
}

export default ChanceCase

usage.js

const underscoredObj = {
  article_id: '1',
  body: 'hello',
  comments: [
    { user_id: 'u1', body: 'wow' },
    { user_id: 'u2', body: 'wow' }
  ],
  author: {
    user_id: 'u1',
    avatar_image: {
      url: 'http://x',
      size: 'large'
    }
  }
}

const camelizedObj = {
  articleId: '1',
  body: 'hello',
  comments: [
    { userId: 'u1', body: 'wow' },
    { userId: 'u2', body: 'wow' }
  ],
  author: {
    userId: 'u1',
    avatarImage: {
      url: 'http://x',
      size: 'large'
    }
  }
}

console.log(CaseChange.convertToCamelcase(underscoredObj))
console.log(CaseChange.convertToUnderscore(camelizedObj))