oAuth.js

/**
 * Attempts to access a non-Google API using a constructed service
 * object.
 *
 * If your add-on needs access to non-Google APIs that require OAuth,
 * you need to implement this method. You can use the OAuth1 and
 * OAuth2 Apps Script libraries to help implement it.
 *
 * @param {String} url         The URL to access.
 * @param {String} method_opt  The HTTP method. Defaults to GET.
 * @param {Object} headers_opt The HTTP headers. Defaults to an empty
 *                             object. The Authorization field is added
 *                             to the headers in this method.
 * @returns {HttpResponse} the result from the UrlFetchApp.fetch() call.
 */
function accessProtectedResource(url, method_opt, headers_opt, payload_opt,content_opt) {
    var service = getOAuthService();
    var maybeAuthorized = service.hasAccess();
    if (maybeAuthorized) {
      // A token is present, but it may be expired or invalid. Make a
      // request and check the response code to be sure.
  
      // Make the UrlFetch request and return the result.
      
      var accessToken = service.getAccessToken();
      var method = method_opt || 'get';
      var headers = headers_opt || {};
      var payload = payload_opt || {};
      var content = content_opt || 'application/x-www-form-urlencoded';
      headers['Authorization'] =
          Utilities.formatString('Bearer %s', accessToken);
      var resp = UrlFetchApp.fetch(url, {
        'headers': headers,
        'method' : method,
        'payload' : payload,
        'contentType' : content,
        'muteHttpExceptions': true, // Prevents thrown HTTP exceptions.
      });
      
      var code = resp.getResponseCode();
      if (code >= 200 && code < 300) {
        return resp.getContentText("utf-8"); // Success
      } else if (code == 401 || code == 403) {
         // Not fully authorized for this action.
         maybeAuthorized = false;
      } else {
         // Handle other response codes by logging them and throwing an
         // exception.
         console.error("Backend server error (%s): %s", code.toString(),
                       resp.getContentText("utf-8"));
         throw ("Backend server error: " + code);
      }
    }
  
    if (!maybeAuthorized) {
      // Invoke the authorization flow using the default authorization
      // prompt card.
      CardService.newAuthorizationException()
          .setAuthorizationUrl(service.getAuthorizationUrl())
          .setResourceDisplayName("Clio practice management data")
          .throwException();
        Logger.log(service.hasAccess());
    }
  }
  
  /**
   * Create a new OAuth service to facilitate accessing an API.
   * This example assumes there is a single service that the add-on needs to
   * access. Its name is used when persisting the authorized token, so ensure
   * it is unique within the scope of the property store. You must set the
   * client secret and client ID, which are obtained when registering your
   * add-on with the API.
   *
   * See the Apps Script OAuth2 Library documentation for more
   * information:
   *   https://github.com/googlesamples/apps-script-oauth2#1-create-the-oauth2-service
   *
   *  @returns A configured OAuth2 service object.
   */
  function getOAuthService() {
    return OAuth2.createService('clio_api')
        .setAuthorizationBaseUrl('https://app.clio.com/oauth/authorize')
        .setTokenUrl('https://app.clio.com/oauth/token')
        .setClientId('ZrxvRba6rxX2Sb7PjPFNBWtXZHiH8Ckb65NiJaBM')
        .setClientSecret('YdrMhGZRXXtlxif9PVlTYrohlXfpsCRzpjV0eLw4')
  //      .setScope('SERVICE_SCOPE_REQUESTS')
        .setCallbackFunction('authCallback')
        .setCache(CacheService.getUserCache())
        .setPropertyStore(PropertiesService.getUserProperties());
  }
  
  /**
   * Boilerplate code to determine if a request is authorized and returns
   * a corresponding HTML message. When the user completes the OAuth2 flow
   * on the service provider's website, this function is invoked from the
   * service. In order for authorization to succeed you must make sure that
   * the service knows how to call this function by setting the correct
   * redirect URL.
   *
   * The redirect URL to enter is:
   * https://script.google.com/macros/d/<Apps Script ID>/usercallback
   *
   * See the Apps Script OAuth2 Library documentation for more
   * information:
   *   https://github.com/googlesamples/apps-script-oauth2#1-create-the-oauth2-service
   *
   *  @param {Object} callbackRequest The request data received from the
   *                  callback function. Pass it to the service's
   *                  handleCallback() method to complete the
   *                  authorization process.
   *  @returns {HtmlOutput} a success or denied HTML message to display to
   *           the user. Also sets a timer to close the window
   *           automatically.
   */
  function authCallback(callbackRequest) {
    var authorized = getOAuthService().handleCallback(callbackRequest);
    if (authorized) {
      return HtmlService.createHtmlOutput(
        'Success! <script>setTimeout(function() { top.window.close() }, 1);</script>');
    } else {
      return HtmlService.createHtmlOutput('Denied');
    }
  }
  
  /**
   * Unauthorizes the non-Google service. This is useful for OAuth
   * development/testing.  Run this method (Run > resetOAuth in the script
   * editor) to reset OAuth to re-prompt the user for OAuth.
   */
  function resetOAuth() {
    getOAuthService().reset();
  }
  
  function getClioAuth() {
    accessProtectedResource('https://app.clio.com/');
  }