transformkeys/lib/index.js

Transforms object properties to another case.

const methods = {
  camel(word, index) {
    return index === 0 ? word : word[0].toUpperCase() + word.slice(1);
  },
  snake(word, index) {
    return index === 0 ? word : '_' + word;
  },
  constant(word, index) {
    return index === 0 ? word.toUpperCase() : '_' + word.toUpperCase();
  },
  dash(word, index) {
    return index === 0 ? word : '-' + word;
  },
  pascal(word) {
    return word[0].toUpperCase() + word.slice(1);
  }
};

const transformKeys = (obj, method = 'camel') => {
  if (typeof method === 'string') method = methods[method];

  if (typeof obj !== 'object') return obj;
  if (!obj) return obj;
  if (Array.isArray(obj)) return obj.map(item => transformKeys(item, method));

  return Object.keys(obj).map(key => ({ key, value: transformKeys(obj[key]) })).map(({ key, value }) => ({
    value,
    key: key.replace(/_|\-/g, ' ').replace(/(\b|^|[a-z])([A-Z])/g, '$1 $2').replace(/ +/g, ' ').trim().toLowerCase().split(' ').reduce((str, word, index) => str + method(word, index), key.startsWith('_') ? '_' : '')
  })).reduce((returned, { key, value }) => Object.assign(returned, { [key]: value }), {});
};

module.exports = transformKeys;