Generate Typescript types based on json data

generate-types.js

function generateTypes(obj, name) {
  const parsed = Object.keys(obj).reduce((str, key) => {
    let type = Array.isArray(obj[key]) ? typeof obj[key][0] : typeof obj[key];

    if (type === 'object') {
      type = key.charAt(0).toUpperCase() + key.slice(1, key.length - 1);
    }

    type = type === 'undefined' ? 'any' : type;
    type = isArray ? type + '[]' : type;

    return `${str}\n\t${key}: ${type};`;
  }, '');

  return `type ${name} = {${parsed}\n}`;
}