kindergarten/lib/rules/Type.js

Kindergarten is a JavaScript library which helps programmers to achieve modular security using sandbox pattern

'use strict';

exports.__esModule = true;
exports.default = undefined;

var _createClass = function () { function defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } } return function (Constructor, protoProps, staticProps) { if (protoProps) defineProperties(Constructor.prototype, protoProps); if (staticProps) defineProperties(Constructor, staticProps); return Constructor; }; }();

var _isArray = require('lodash/isArray');

var _isArray2 = _interopRequireDefault(_isArray);

var _isString = require('lodash/isString');

var _isString2 = _interopRequireDefault(_isString);

var _AllowedMethodsService = require('../utils/AllowedMethodsService');

var _AllowedMethodsService2 = _interopRequireDefault(_AllowedMethodsService);

var _errors = require('../errors');

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }

// The basic RegEx for validating that rule string is correct. The type of the
// rule is later on validated using AllowedMethodsService as well.
var TYPE_REGEX = /^can(not)? ([a-z_$][a-zA-Z0-9_$]*)$/;

/**
 * Implementation of the Rule Type class.
 * Type is responsible for the rule string e.g. `can watch` validation and
 * for extracting all relevant infos out of that string.
 */

var Type = function () {
  function Type(rule, str) {
    _classCallCheck(this, Type);

    var match = (0, _isString2.default)(str) && str.match(TYPE_REGEX);

    // Extract type of the rule.
    // e.g. "cannot watch" => "watch"
    this.type = function () {
      return (0, _isArray2.default)(match) ? match[2] : undefined;
    }();

    /**
     * Just store the given string. Used internally by Type class.
     */
    this.raw = str;

    /**
     * Reference to a original rule
     */
    this.rule = rule;

    this.validate();

    // 'can' rules are positive 'cannot' rules are NOT positive.
    this._isPositive = !match[1];
  }

  /**
   * Throws an error if the type of the rule is not applicable.
   */


  _createClass(Type, [{
    key: 'validate',
    value: function validate() {
      var allowedMethodsService = new _AllowedMethodsService2.default();
      var type = this.type;

      if (!(0, _isString2.default)(type) || allowedMethodsService.isRestricted(type)) {
        throw new _errors.WrongRuleDefinition('Cannot create a rule ' + this.raw + '. The type of the rule cannot be parsed.');
      }

      return true;
    }

    /**
     * `can` rules are positive `cannot` rules are negative.
     */

  }, {
    key: 'isPositive',
    value: function isPositive() {
      return !!this._isPositive;
    }

    /**
     * Opposite of `isPositive()` method.
     */

  }, {
    key: 'isNegative',
    value: function isNegative() {
      return !this.isPositive();
    }
  }]);

  return Type;
}();

exports.default = Type;