@appzmonster/msal-token-interceptor/MsalTokenHandler.js

Msal-Token-Interceptor is a request interceptor which uses Microsoft MSAL to handle OAuth 2.0 token exchange with Microsoft Identity Platform during a fetch request. This is part of fetch-interceptor family.

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.MsalTokenHandler = void 0;

var _fetchInterceptor = require("@appzmonster/fetch-interceptor");

var _msalBrowser = require("@azure/msal-browser");

function _typeof(obj) { "@babel/helpers - typeof"; if (typeof Symbol === "function" && typeof Symbol.iterator === "symbol") { _typeof = function _typeof(obj) { return typeof obj; }; } else { _typeof = function _typeof(obj) { return obj && typeof Symbol === "function" && obj.constructor === Symbol && obj !== Symbol.prototype ? "symbol" : typeof obj; }; } return _typeof(obj); }

function asyncGeneratorStep(gen, resolve, reject, _next, _throw, key, arg) { try { var info = gen[key](arg); var value = info.value; } catch (error) { reject(error); return; } if (info.done) { resolve(value); } else { Promise.resolve(value).then(_next, _throw); } }

function _asyncToGenerator(fn) { return function () { var self = this, args = arguments; return new Promise(function (resolve, reject) { var gen = fn.apply(self, args); function _next(value) { asyncGeneratorStep(gen, resolve, reject, _next, _throw, "next", value); } function _throw(err) { asyncGeneratorStep(gen, resolve, reject, _next, _throw, "throw", err); } _next(undefined); }); }; }

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

function _createClass(Constructor, protoProps, staticProps) { if (protoProps) _defineProperties(Constructor.prototype, protoProps); if (staticProps) _defineProperties(Constructor, staticProps); return Constructor; }

function _get(target, property, receiver) { if (typeof Reflect !== "undefined" && Reflect.get) { _get = Reflect.get; } else { _get = function _get(target, property, receiver) { var base = _superPropBase(target, property); if (!base) return; var desc = Object.getOwnPropertyDescriptor(base, property); if (desc.get) { return desc.get.call(receiver); } return desc.value; }; } return _get(target, property, receiver || target); }

function _superPropBase(object, property) { while (!Object.prototype.hasOwnProperty.call(object, property)) { object = _getPrototypeOf(object); if (object === null) break; } return object; }

function _inherits(subClass, superClass) { if (typeof superClass !== "function" && superClass !== null) { throw new TypeError("Super expression must either be null or a function"); } subClass.prototype = Object.create(superClass && superClass.prototype, { constructor: { value: subClass, writable: true, configurable: true } }); if (superClass) _setPrototypeOf(subClass, superClass); }

function _setPrototypeOf(o, p) { _setPrototypeOf = Object.setPrototypeOf || function _setPrototypeOf(o, p) { o.__proto__ = p; return o; }; return _setPrototypeOf(o, p); }

function _createSuper(Derived) { var hasNativeReflectConstruct = _isNativeReflectConstruct(); return function _createSuperInternal() { var Super = _getPrototypeOf(Derived), result; if (hasNativeReflectConstruct) { var NewTarget = _getPrototypeOf(this).constructor; result = Reflect.construct(Super, arguments, NewTarget); } else { result = Super.apply(this, arguments); } return _possibleConstructorReturn(this, result); }; }

function _possibleConstructorReturn(self, call) { if (call && (_typeof(call) === "object" || typeof call === "function")) { return call; } return _assertThisInitialized(self); }

function _assertThisInitialized(self) { if (self === void 0) { throw new ReferenceError("this hasn't been initialised - super() hasn't been called"); } return self; }

function _isNativeReflectConstruct() { if (typeof Reflect === "undefined" || !Reflect.construct) return false; if (Reflect.construct.sham) return false; if (typeof Proxy === "function") return true; try { Boolean.prototype.valueOf.call(Reflect.construct(Boolean, [], function () {})); return true; } catch (e) { return false; } }

function _getPrototypeOf(o) { _getPrototypeOf = Object.setPrototypeOf ? Object.getPrototypeOf : function _getPrototypeOf(o) { return o.__proto__ || Object.getPrototypeOf(o); }; return _getPrototypeOf(o); }

var MsalTokenHandler = /*#__PURE__*/function (_BaseInterceptor) {
  _inherits(MsalTokenHandler, _BaseInterceptor);

  var _super = _createSuper(MsalTokenHandler);

  function MsalTokenHandler(tokenRequest, msalInstance, setAccount) {
    var _this;

    _classCallCheck(this, MsalTokenHandler);

    _this = _super.call(this);
    _this._msalInstance = msalInstance;
    _this._tokenRequest = tokenRequest;
    _this._setAccount = setAccount;
    var defaultValue = MsalTokenHandler.getDefault();

    if (defaultValue != null) {
      _this._defaultMsalInstance = defaultValue.msalInstance;
      _this._defaultTokenRequest = defaultValue.tokenRequest;
    }

    _this._token = null;
    return _this;
  }

  _createClass(MsalTokenHandler, [{
    key: "invoke",
    value: function () {
      var _invoke = _asyncToGenerator( /*#__PURE__*/regeneratorRuntime.mark(function _callee(resource, init) {
        var authorizationHeader;
        return regeneratorRuntime.wrap(function _callee$(_context) {
          while (1) {
            switch (_context.prev = _context.next) {
              case 0:
                // Reset the token before invoking a new token request.
                this._token = null; // Exchange token with auth server.

                _context.next = 3;
                return this._acquireToken();

              case 3:
                this._token = _context.sent;

                if (!(this._token != null && this._token.accessToken != null)) {
                  _context.next = 9;
                  break;
                }

                authorizationHeader = {
                  Authorization: "Bearer ".concat(this._token.accessToken)
                };
                init.headers = Object.assign({}, init.headers, authorizationHeader);
                _context.next = 10;
                break;

              case 9:
                throw new Error("Unable to exchange a valid token with authorization server");

              case 10:
                _context.next = 12;
                return _get(_getPrototypeOf(MsalTokenHandler.prototype), "fetch", this).call(this, resource, init);

              case 12:
                return _context.abrupt("return", _context.sent);

              case 13:
              case "end":
                return _context.stop();
            }
          }
        }, _callee, this);
      }));

      function invoke(_x, _x2) {
        return _invoke.apply(this, arguments);
      }

      return invoke;
    }()
  }, {
    key: "token",
    value: function () {
      var _token = _asyncToGenerator( /*#__PURE__*/regeneratorRuntime.mark(function _callee2() {
        return regeneratorRuntime.wrap(function _callee2$(_context2) {
          while (1) {
            switch (_context2.prev = _context2.next) {
              case 0:
                return _context2.abrupt("return", this._token);

              case 1:
              case "end":
                return _context2.stop();
            }
          }
        }, _callee2, this);
      }));

      function token() {
        return _token.apply(this, arguments);
      }

      return token;
    }()
  }, {
    key: "_getMsalInstance",
    value: function _getMsalInstance() {
      var msalInstance = null;

      if (this._msalInstance != null) {
        msalInstance = this._msalInstance;
      } else {
        msalInstance = this._defaultMsalInstance;
      }

      if (msalInstance == null) {
        throw new Error('MSAL instance is missing from both default registration and current request');
      }

      return msalInstance;
    }
  }, {
    key: "_acquireToken",
    value: function () {
      var _acquireToken2 = _asyncToGenerator( /*#__PURE__*/regeneratorRuntime.mark(function _callee3() {
        var request, token;
        return regeneratorRuntime.wrap(function _callee3$(_context3) {
          while (1) {
            switch (_context3.prev = _context3.next) {
              case 0:
                request = Object.assign({}, this._tokenRequest);
                token = null;

                if (request.account == null) {
                  request.account = this._getUserAccount();
                } // Use registered default redirect uri (if any) if request does not set 
                // redirect uri. If no redirect uri is set at the request level, it will 
                // fallback using the redirect uri configured at msal instance level.


                if ('redirectUri' in request === false) {
                  if (_typeof(this._defaultTokenRequest) === 'object' && typeof this._defaultTokenRequest.redirectUri === 'string') {
                    request.redirectUri = this._defaultTokenRequest.redirectUri;
                  }
                } // If token is not found in the local cache or near expiration, msal will 
                // attempt to exchange a new token with the authorization server using a 
                // hidden iframe. Msal will cache the response token in local cache. Such 
                // flow is call silent authentication and is achieved via the authorization 
                // endpoint with 'prompt' query string set as 'none'.


                console.log("request", request);
                _context3.next = 7;
                return this._getMsalInstance().acquireTokenSilent(request);

              case 7:
                token = _context3.sent;

                if (!(token == null)) {
                  _context3.next = 10;
                  break;
                }

                throw new Error("Unable to exchange a valid token with authorization server");

              case 10:
                return _context3.abrupt("return", token);

              case 11:
              case "end":
                return _context3.stop();
            }
          }
        }, _callee3, this);
      }));

      function _acquireToken() {
        return _acquireToken2.apply(this, arguments);
      }

      return _acquireToken;
    }()
  }, {
    key: "_getUserAccount",
    value: function _getUserAccount() {
      var userAccount = null;

      var userAccounts = this._getMsalInstance().getAllAccounts();

      if (this._setAccount != null) {
        userAccount = this._setAccount(userAccounts);
      } else {
        if (userAccounts != null && userAccounts instanceof Array && userAccounts.length > 0) {
          userAccount = userAccounts[0];
        }
      }

      return userAccount;
    }
  }]);

  return MsalTokenHandler;
}(_fetchInterceptor.BaseInterceptor);

exports.MsalTokenHandler = MsalTokenHandler;

MsalTokenHandler.registerDefault = function (defaultMsalInstance, defaultTokenRequest) {
  if ('fetch' in window === false) {
    return;
  }

  if ('with' in window.fetch === false || typeof window.fetch["with"] !== 'function') {
    console.error('Unable to register default MSAL token handler interceptor because @appzmonster/fetch-interceptor dependency is not found');
    return;
  }

  var fetchManager = window.fetch["with"];
  fetchManager._defaultMsalTokenHandler = {
    msalInstance: defaultMsalInstance,
    tokenRequest: defaultTokenRequest
  };
};

MsalTokenHandler.getDefault = function () {
  var defaultValue = null;

  if ('fetch' in window && 'with' in window.fetch && _typeof(window.fetch["with"]._defaultMsalTokenHandler) === 'object') {
    defaultValue = window.fetch["with"]._defaultMsalTokenHandler;
  }

  return defaultValue;
};