Handy script to auto generate mongoose schema from existing data

genschema.js

var prefix = Math.random();
function parse(obj) {
  var key, value, type, schema;
  type = obj.constructor.name;
  switch (type) {
    case 'Object':
      schema = {};
      for (key in obj) {
        value = parseKey(key, obj);
        if (value !== undefined) schema[key] = value;
      }
      return schema;
    case 'Array':
      value = parseKey(0, obj);
      schema = [];
      if (value !== undefined) schema.push(value);
      return schema;
    default:
      return prefix + type;
  }
}

function parseKey(key, obj) {
  var type;
  if (obj[key] !== undefined) {
    type = obj[key].constructor.name;
    switch (type) {
      case 'Object':
      case 'Array':
        return parse(obj[key]);
      default:
        return prefix + type;
    }
  }
}
function stringToConstructor(schema) {
  var str = JSON.stringify(schema);
  return str.replace(new RegExp('"' + prefix + '(\\S+?)"', 'g'), '$1');
}
console.log(stringToConstructor(parse(require('./book-isbn'))));

You can then use something like js beautify to pretty print you schema

good i like it