dropbox/es/src/auth.js

The Dropbox JavaScript SDK is a lightweight, promise based interface to the Dropbox v2 API that works in both nodejs and browser environments.

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; }

import { getTokenExpiresAtDate, isBrowserEnv, createBrowserSafeString, OAuth2AuthorizationUrl, OAuth2TokenUrl, isWorkerEnv } from './utils.js';
import { parseResponse } from './response.js';
var fetch;
var crypto;
var Encoder; // Expiration is 300 seconds but needs to be in milliseconds for Date object

var TokenExpirationBuffer = 300 * 1000;
var PKCELength = 128;
var TokenAccessTypes = ['legacy', 'offline', 'online'];
var GrantTypes = ['code', 'token'];
var IncludeGrantedScopes = ['none', 'user', 'team'];
/**
 * @class DropboxAuth
 * @classdesc The DropboxAuth class that provides methods to manage, acquire, and refresh tokens.
 * @arg {Object} options
 * @arg {Function} [options.fetch] - fetch library for making requests.
 * @arg {String} [options.accessToken] - An access token for making authenticated
 * requests.
 * @arg {Date} [options.AccessTokenExpiresAt] - Date of the current access token's
 * expiration (if available)
 * @arg {String} [options.refreshToken] - A refresh token for retrieving access tokens
 * @arg {String} [options.clientId] - The client id for your app. Used to create
 * authentication URL.
 * @arg {String} [options.clientSecret] - The client secret for your app. Used to create
 * authentication URL and refresh access tokens.
 * @arg {String} [options.domain] - A custom domain to use when making api requests. This
 * should only be used for testing as scaffolding to avoid making network requests.
 * @arg {String} [options.domainDelimiter] - A custom delimiter to use when separating domain from
 * subdomain. This should only be used for testing as scaffolding.
 * @arg {Object} [options.customHeaders] - An object (in the form of header: value) designed to set
 * custom headers to use during a request.
 * @arg {Boolean} [options.dataOnBody] - Whether request data is sent on body or as URL params.
  * Defaults to false.
*/

var DropboxAuth = /*#__PURE__*/function () {
  function DropboxAuth(options) {
    _classCallCheck(this, DropboxAuth);

    options = options || {};

    if (isBrowserEnv()) {
      fetch = window.fetch.bind(window);
      crypto = window.crypto || window.msCrypto; // for IE11
    } else if (isWorkerEnv()) {
      /* eslint-disable no-restricted-globals */
      fetch = self.fetch.bind(self);
      crypto = self.crypto;
      /* eslint-enable no-restricted-globals */
    } else {
      fetch = require('node-fetch'); // eslint-disable-line global-require

      crypto = require('crypto'); // eslint-disable-line global-require
    }

    if (typeof TextEncoder === 'undefined') {
      Encoder = require('util').TextEncoder; // eslint-disable-line global-require
    } else {
      Encoder = TextEncoder;
    }

    this.fetch = options.fetch || fetch;
    this.accessToken = options.accessToken;
    this.accessTokenExpiresAt = options.accessTokenExpiresAt;
    this.refreshToken = options.refreshToken;
    this.clientId = options.clientId;
    this.clientSecret = options.clientSecret;
    this.domain = options.domain;
    this.domainDelimiter = options.domainDelimiter;
    this.customHeaders = options.customHeaders;
    this.dataOnBody = options.dataOnBody;
  }
  /**
     * Set the access token used to authenticate requests to the API.
     * @arg {String} accessToken - An access token
     * @returns {undefined}
     */


  _createClass(DropboxAuth, [{
    key: "setAccessToken",
    value: function setAccessToken(accessToken) {
      this.accessToken = accessToken;
    }
    /**
       * Get the access token
       * @returns {String} Access token
       */

  }, {
    key: "getAccessToken",
    value: function getAccessToken() {
      return this.accessToken;
    }
    /**
       * Set the client id, which is used to help gain an access token.
       * @arg {String} clientId - Your apps client id
       * @returns {undefined}
       */

  }, {
    key: "setClientId",
    value: function setClientId(clientId) {
      this.clientId = clientId;
    }
    /**
       * Get the client id
       * @returns {String} Client id
       */

  }, {
    key: "getClientId",
    value: function getClientId() {
      return this.clientId;
    }
    /**
       * Set the client secret
       * @arg {String} clientSecret - Your app's client secret
       * @returns {undefined}
       */

  }, {
    key: "setClientSecret",
    value: function setClientSecret(clientSecret) {
      this.clientSecret = clientSecret;
    }
    /**
       * Get the client secret
       * @returns {String} Client secret
       */

  }, {
    key: "getClientSecret",
    value: function getClientSecret() {
      return this.clientSecret;
    }
    /**
       * Gets the refresh token
       * @returns {String} Refresh token
       */

  }, {
    key: "getRefreshToken",
    value: function getRefreshToken() {
      return this.refreshToken;
    }
    /**
       * Sets the refresh token
       * @param refreshToken - A refresh token
       */

  }, {
    key: "setRefreshToken",
    value: function setRefreshToken(refreshToken) {
      this.refreshToken = refreshToken;
    }
    /**
       * Gets the access token's expiration date
       * @returns {Date} date of token expiration
       */

  }, {
    key: "getAccessTokenExpiresAt",
    value: function getAccessTokenExpiresAt() {
      return this.accessTokenExpiresAt;
    }
    /**
       * Sets the access token's expiration date
       * @param accessTokenExpiresAt - new expiration date
       */

  }, {
    key: "setAccessTokenExpiresAt",
    value: function setAccessTokenExpiresAt(accessTokenExpiresAt) {
      this.accessTokenExpiresAt = accessTokenExpiresAt;
    }
    /**
       * Sets the code verifier for PKCE flow
       * @param {String} codeVerifier - new code verifier
       */

  }, {
    key: "setCodeVerifier",
    value: function setCodeVerifier(codeVerifier) {
      this.codeVerifier = codeVerifier;
    }
    /**
       * Gets the code verifier for PKCE flow
       * @returns {String} - code verifier for PKCE
       */

  }, {
    key: "getCodeVerifier",
    value: function getCodeVerifier() {
      return this.codeVerifier;
    }
  }, {
    key: "generateCodeChallenge",
    value: function generateCodeChallenge() {
      var _this = this;

      var encoder = new Encoder();
      var codeData = encoder.encode(this.codeVerifier);
      var codeChallenge;

      if (isBrowserEnv() || isWorkerEnv()) {
        return crypto.subtle.digest('SHA-256', codeData).then(function (digestedHash) {
          var base64String = btoa(String.fromCharCode.apply(null, new Uint8Array(digestedHash)));
          codeChallenge = createBrowserSafeString(base64String).substr(0, 128);
          _this.codeChallenge = codeChallenge;
        });
      }

      var digestedHash = crypto.createHash('sha256').update(codeData).digest();
      codeChallenge = createBrowserSafeString(digestedHash);
      this.codeChallenge = codeChallenge;
      return Promise.resolve();
    }
  }, {
    key: "generatePKCECodes",
    value: function generatePKCECodes() {
      var codeVerifier;

      if (isBrowserEnv() || isWorkerEnv()) {
        var array = new Uint8Array(PKCELength);
        var randomValueArray = crypto.getRandomValues(array);
        var base64String = btoa(randomValueArray);
        codeVerifier = createBrowserSafeString(base64String).substr(0, 128);
      } else {
        var randomBytes = crypto.randomBytes(PKCELength);
        codeVerifier = createBrowserSafeString(randomBytes).substr(0, 128);
      }

      this.codeVerifier = codeVerifier;
      return this.generateCodeChallenge();
    }
    /**
       * Get a URL that can be used to authenticate users for the Dropbox API.
       * @arg {String} redirectUri - A URL to redirect the user to after
       * authenticating. This must be added to your app through the admin interface.
       * @arg {String} [state] - State that will be returned in the redirect URL to help
       * prevent cross site scripting attacks.
       * @arg {String} [authType] - auth type, defaults to 'token', other option is 'code'
       * @arg {String} [tokenAccessType] - type of token to request.  From the following:
       * null - creates a token with the app default (either legacy or online)
       * legacy - creates one long-lived token with no expiration
       * online - create one short-lived token with an expiration
       * offline - create one short-lived token with an expiration with a refresh token
       * @arg {Array<String>} [scope] - scopes to request for the grant
       * @arg {String} [includeGrantedScopes] - whether or not to include previously granted scopes.
       * From the following:
       * user - include user scopes in the grant
       * team - include team scopes in the grant
       * Note: if this user has never linked the app, include_granted_scopes must be None
       * @arg {boolean} [usePKCE] - Whether or not to use Sha256 based PKCE. PKCE should be only use
       * on client apps which doesn't call your server. It is less secure than non-PKCE flow but
       * can be used if you are unable to safely retrieve your app secret
       * @returns {Promise<String>} - Url to send user to for Dropbox API authentication
       * returned in a promise
       */

  }, {
    key: "getAuthenticationUrl",
    value: function getAuthenticationUrl(redirectUri, state) {
      var _this2 = this;

      var authType = arguments.length > 2 && arguments[2] !== undefined ? arguments[2] : 'token';
      var tokenAccessType = arguments.length > 3 && arguments[3] !== undefined ? arguments[3] : null;
      var scope = arguments.length > 4 && arguments[4] !== undefined ? arguments[4] : null;
      var includeGrantedScopes = arguments.length > 5 && arguments[5] !== undefined ? arguments[5] : 'none';
      var usePKCE = arguments.length > 6 && arguments[6] !== undefined ? arguments[6] : false;
      var clientId = this.getClientId();
      var baseUrl = OAuth2AuthorizationUrl(this.domain);

      if (!clientId) {
        throw new Error('A client id is required. You can set the client id using .setClientId().');
      }

      if (authType !== 'code' && !redirectUri) {
        throw new Error('A redirect uri is required.');
      }

      if (!GrantTypes.includes(authType)) {
        throw new Error('Authorization type must be code or token');
      }

      if (tokenAccessType && !TokenAccessTypes.includes(tokenAccessType)) {
        throw new Error('Token Access Type must be legacy, offline, or online');
      }

      if (scope && !(scope instanceof Array)) {
        throw new Error('Scope must be an array of strings');
      }

      if (!IncludeGrantedScopes.includes(includeGrantedScopes)) {
        throw new Error('includeGrantedScopes must be none, user, or team');
      }

      var authUrl;

      if (authType === 'code') {
        authUrl = "".concat(baseUrl, "?response_type=code&client_id=").concat(clientId);
      } else {
        authUrl = "".concat(baseUrl, "?response_type=token&client_id=").concat(clientId);
      }

      if (redirectUri) {
        authUrl += "&redirect_uri=".concat(redirectUri);
      }

      if (state) {
        authUrl += "&state=".concat(state);
      }

      if (tokenAccessType) {
        authUrl += "&token_access_type=".concat(tokenAccessType);
      }

      if (scope) {
        authUrl += "&scope=".concat(scope.join(' '));
      }

      if (includeGrantedScopes !== 'none') {
        authUrl += "&include_granted_scopes=".concat(includeGrantedScopes);
      }

      if (usePKCE) {
        return this.generatePKCECodes().then(function () {
          authUrl += '&code_challenge_method=S256';
          authUrl += "&code_challenge=".concat(_this2.codeChallenge);
          return authUrl;
        });
      }

      return Promise.resolve(authUrl);
    }
    /**
       * Get an OAuth2 access token from an OAuth2 Code.
       * @arg {String} redirectUri - A URL to redirect the user to after
       * authenticating. This must be added to your app through the admin interface.
       * @arg {String} code - An OAuth2 code.
       * @returns {Object} An object containing the token and related info (if applicable)
       */

  }, {
    key: "getAccessTokenFromCode",
    value: function getAccessTokenFromCode(redirectUri, code) {
      var clientId = this.getClientId();
      var clientSecret = this.getClientSecret();

      if (!clientId) {
        throw new Error('A client id is required. You can set the client id using .setClientId().');
      }

      var path = OAuth2TokenUrl(this.domain, this.domainDelimiter);
      path += '?grant_type=authorization_code';
      path += "&code=".concat(code);
      path += "&client_id=".concat(clientId);

      if (clientSecret) {
        path += "&client_secret=".concat(clientSecret);
      } else {
        if (!this.codeVerifier) {
          throw new Error('You must use PKCE when generating the authorization URL to not include a client secret');
        }

        path += "&code_verifier=".concat(this.codeVerifier);
      }

      if (redirectUri) {
        path += "&redirect_uri=".concat(redirectUri);
      }

      var fetchOptions = {
        method: 'POST',
        headers: {
          'Content-Type': 'application/x-www-form-urlencoded'
        }
      };
      return this.fetch(path, fetchOptions).then(function (res) {
        return parseResponse(res);
      });
    }
    /**
       * Checks if a token is needed, can be refreshed and if the token is expired.
       * If so, attempts to refresh access token
       * @returns {Promise<*>}
       */

  }, {
    key: "checkAndRefreshAccessToken",
    value: function checkAndRefreshAccessToken() {
      var canRefresh = this.getRefreshToken() && this.getClientId();
      var needsRefresh = !this.getAccessTokenExpiresAt() || new Date(Date.now() + TokenExpirationBuffer) >= this.getAccessTokenExpiresAt();
      var needsToken = !this.getAccessToken();

      if ((needsRefresh || needsToken) && canRefresh) {
        return this.refreshAccessToken();
      }

      return Promise.resolve();
    }
    /**
       * Refreshes the access token using the refresh token, if available
       * @arg {Array<String>} scope - a subset of scopes from the original
       * refresh to acquire with an access token
       * @returns {Promise<*>}
       */

  }, {
    key: "refreshAccessToken",
    value: function refreshAccessToken() {
      var _this3 = this;

      var scope = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : null;
      var clientId = this.getClientId();
      var clientSecret = this.getClientSecret();

      if (!clientId) {
        throw new Error('A client id is required. You can set the client id using .setClientId().');
      }

      if (scope && !(scope instanceof Array)) {
        throw new Error('Scope must be an array of strings');
      }

      var refreshUrl = OAuth2TokenUrl(this.domain, this.domainDelimiter);
      var fetchOptions = {
        headers: {
          'Content-Type': 'application/json'
        },
        method: 'POST'
      };

      if (this.dataOnBody) {
        var body = {
          grant_type: 'refresh_token',
          client_id: clientId,
          refresh_token: this.getRefreshToken()
        };

        if (clientSecret) {
          body.client_secret = clientSecret;
        }

        if (scope) {
          body.scope = scope.join(' ');
        }

        fetchOptions.body = body;
      } else {
        refreshUrl += "?grant_type=refresh_token&refresh_token=".concat(this.getRefreshToken());
        refreshUrl += "&client_id=".concat(clientId);

        if (clientSecret) {
          refreshUrl += "&client_secret=".concat(clientSecret);
        }

        if (scope) {
          refreshUrl += "&scope=".concat(scope.join(' '));
        }
      }

      return this.fetch(refreshUrl, fetchOptions).then(function (res) {
        return parseResponse(res);
      }).then(function (res) {
        _this3.setAccessToken(res.result.access_token);

        _this3.setAccessTokenExpiresAt(getTokenExpiresAtDate(res.result.expires_in));
      });
    }
  }]);

  return DropboxAuth;
}();

export { DropboxAuth as default };