Quickstart: Add-on for Google Forms

Complete the steps described in the rest of this page, and in about ten minutes you'll have created a Google Forms add-on that uses triggers to send an email when a user responds to the form. To see what the add-on looks like when it's finished, just install Form Notifications from the Google Forms Add-ons store.

Set it up

1. Create a new Google Form. If you are presented with a welcome screen, give the form a title and choose a theme.
2. From within your new form, click the More menu and select Script editor.... If you are presented with a welcome screen, click Blank Project.
3. Create a new HTML file by selecting the menu item File > New > HTML file. Name this file Sidebar (Apps Script adds the .html extension automatically).
4. Repeat the previous step to create one more HTML file named About.html.
5. Replace the content of those files with the following content, respectively:

code.gs

forms/notifications/notification.gs

View on GitHub

/**
 * @OnlyCurrentDoc
 *
 * The above comment directs Apps Script to limit the scope of file
 * access for this add-on. It specifies that this add-on will only
 * attempt to read or modify the files in which the add-on is used,
 * and not all of the user's files. The authorization request message
 * presented to users will reflect this limited scope.
 */

/**
 * A global constant String holding the title of the add-on. This is
 * used to identify the add-on in the notification emails.
 */
var ADDON_TITLE = 'Form Notifications';

/**
 * A global constant 'notice' text to include with each email
 * notification.
 */
var NOTICE = 'Form Notifications was created as an sample add-on, and is meant for' +
'demonstration purposes only. It should not be used for complex or important' +
'workflows. The number of notifications this add-on produces are limited by the' +
'owner\'s available email quota; it will not send email notifications if the' +
'owner\'s daily email quota has been exceeded. Collaborators using this add-on on' +
'the same form will be able to adjust the notification settings, but will not be' +
'able to disable the notification triggers set by other collaborators.';

/**
 * Adds a custom menu to the active form to show the add-on sidebar.
 *
 * @param {object} e The event parameter for a simple onOpen trigger. To
 *     determine which authorization mode (ScriptApp.AuthMode) the trigger is
 *     running in, inspect e.authMode.
 */
function onOpen(e) {
  FormApp.getUi()
      .createAddonMenu()
      .addItem('Configure notifications', 'showSidebar')
      .addItem('About', 'showAbout')
      .addToUi();
}

/**
 * Runs when the add-on is installed.
 *
 * @param {object} e The event parameter for a simple onInstall trigger. To
 *     determine which authorization mode (ScriptApp.AuthMode) the trigger is
 *     running in, inspect e.authMode. (In practice, onInstall triggers always
 *     run in AuthMode.FULL, but onOpen triggers may be AuthMode.LIMITED or
 *     AuthMode.NONE).
 */
function onInstall(e) {
  onOpen(e);
}

/**
 * Opens a sidebar in the form containing the add-on's user interface for
 * configuring the notifications this add-on will produce.
 */
function showSidebar() {
  var ui = HtmlService.createHtmlOutputFromFile('Sidebar')
      .setSandboxMode(HtmlService.SandboxMode.IFRAME)
      .setTitle('Form Notifications');
  FormApp.getUi().showSidebar(ui);
}

/**
 * Opens a purely-informational dialog in the form explaining details about
 * this add-on.
 */
function showAbout() {
  var ui = HtmlService.createHtmlOutputFromFile('About')
      .setSandboxMode(HtmlService.SandboxMode.IFRAME)
      .setWidth(420)
      .setHeight(270);
  FormApp.getUi().showModalDialog(ui, 'About Form Notifications');
}

/**
 * Save sidebar settings to this form's Properties, and update the onFormSubmit
 * trigger as needed.
 *
 * @param {Object} settings An Object containing key-value
 *      pairs to store.
 */
function saveSettings(settings) {
  PropertiesService.getDocumentProperties().setProperties(settings);
  adjustFormSubmitTrigger();
}

/**
 * Queries the User Properties and adds additional data required to populate
 * the sidebar UI elements.
 *
 * @return {Object} A collection of Property values and
 *     related data used to fill the configuration sidebar.
 */
function getSettings() {
  var settings = PropertiesService.getDocumentProperties().getProperties();

  // Use a default email if the creator email hasn't been provided yet.
  if (!settings.creatorEmail) {
    settings.creatorEmail = Session.getEffectiveUser().getEmail();
  }

  // Get text field items in the form and compile a list
  //   of their titles and IDs.
  var form = FormApp.getActiveForm();
  var textItems = form.getItems(FormApp.ItemType.TEXT);
  settings.textItems = [];
  for (var i = 0; i < textItems.length; i++) {
    settings.textItems.push({
      title: textItems[i].getTitle(),
      id: textItems[i].getId()
    });
  }
  return settings;
}

/**
 * Adjust the onFormSubmit trigger based on user's requests.
 */
function adjustFormSubmitTrigger() {
  var form = FormApp.getActiveForm();
  var triggers = ScriptApp.getUserTriggers(form);
  var settings = PropertiesService.getDocumentProperties();
  var triggerNeeded =
      settings.getProperty('creatorNotify') == 'true' ||
      settings.getProperty('respondentNotify') == 'true';

  // Create a new trigger if required; delete existing trigger
  //   if it is not needed.
  var existingTrigger = null;
  for (var i = 0; i < triggers.length; i++) {
    if (triggers[i].getEventType() == ScriptApp.EventType.ON_FORM_SUBMIT) {
      existingTrigger = triggers[i];
      break;
    }
  }
  if (triggerNeeded && !existingTrigger) {
    var trigger = ScriptApp.newTrigger('respondToFormSubmit')
        .forForm(form)
        .onFormSubmit()
        .create();
  } else if (!triggerNeeded && existingTrigger) {
    ScriptApp.deleteTrigger(existingTrigger);
  }
}

/**
 * Responds to a form submission event if an onFormSubmit trigger has been
 * enabled.
 *
 * @param {Object} e The event parameter created by a form
 *      submission; see
 *      https://developers.google.com/apps-script/understanding_events
 */
function respondToFormSubmit(e) {
  var settings = PropertiesService.getDocumentProperties();
  var authInfo = ScriptApp.getAuthorizationInfo(ScriptApp.AuthMode.FULL);

  // Check if the actions of the trigger require authorizations that have not
  // been supplied yet -- if so, warn the active user via email (if possible).
  // This check is required when using triggers with add-ons to maintain
  // functional triggers.
  if (authInfo.getAuthorizationStatus() ==
      ScriptApp.AuthorizationStatus.REQUIRED) {
    // Re-authorization is required. In this case, the user needs to be alerted
    // that they need to reauthorize; the normal trigger action is not
    // conducted, since authorization needs to be provided first. Send at
    // most one 'Authorization Required' email a day, to avoid spamming users
    // of the add-on.
    sendReauthorizationRequest();
  } else {
    // All required authorizations have been granted, so continue to respond to
    // the trigger event.

    // Check if the form creator needs to be notified; if so, construct and
    // send the notification.
    if (settings.getProperty('creatorNotify') == 'true') {
      sendCreatorNotification();
    }

    // Check if the form respondent needs to be notified; if so, construct and
    // send the notification. Be sure to respect the remaining email quota.
    if (settings.getProperty('respondentNotify') == 'true' &&
        MailApp.getRemainingDailyQuota() > 0) {
      sendRespondentNotification(e.response);
    }
  }
}


/**
 * Called when the user needs to reauthorize. Sends the user of the
 * add-on an email explaining the need to reauthorize and provides
 * a link for the user to do so. Capped to send at most one email
 * a day to prevent spamming the users of the add-on.
 */
function sendReauthorizationRequest() {
  var settings = PropertiesService.getDocumentProperties();
  var authInfo = ScriptApp.getAuthorizationInfo(ScriptApp.AuthMode.FULL);
  var lastAuthEmailDate = settings.getProperty('lastAuthEmailDate');
  var today = new Date().toDateString();
  if (lastAuthEmailDate != today) {
    if (MailApp.getRemainingDailyQuota() > 0) {
      var template =
          HtmlService.createTemplateFromFile('AuthorizationEmail');
      template.url = authInfo.getAuthorizationUrl();
      template.notice = NOTICE;
      var message = template.evaluate();
      MailApp.sendEmail(Session.getEffectiveUser().getEmail(),
          'Authorization Required',
          message.getContent(), {
            name: ADDON_TITLE,
            htmlBody: message.getContent()
          });
    }
    settings.setProperty('lastAuthEmailDate', today);
  }
}

/**
 * Sends out creator notification email(s) if the current number
 * of form responses is an even multiple of the response step
 * setting.
 */
function sendCreatorNotification() {
  var form = FormApp.getActiveForm();
  var settings = PropertiesService.getDocumentProperties();
  var responseStep = settings.getProperty('responseStep');
  responseStep = responseStep ? parseInt(responseStep) : 10;

  // If the total number of form responses is an even multiple of the
  // response step setting, send a notification email(s) to the form
  // creator(s). For example, if the response step is 10, notifications
  // will be sent when there are 10, 20, 30, etc. total form responses
  // received.
  if (form.getResponses().length % responseStep == 0) {
    var addresses = settings.getProperty('creatorEmail').split(',');
    if (MailApp.getRemainingDailyQuota() > addresses.length) {
      var template =
          HtmlService.createTemplateFromFile('CreatorNotification');
      template.sheet =
          DriveApp.getFileById(form.getDestinationId()).getUrl();
      template.summary = form.getSummaryUrl();
      template.responses = form.getResponses().length;
      template.title = form.getTitle();
      template.responseStep = responseStep;
      template.formUrl = form.getEditUrl();
      template.notice = NOTICE;
      var message = template.evaluate();
      MailApp.sendEmail(settings.getProperty('creatorEmail'),
          form.getTitle() + ': Form submissions detected',
          message.getContent(), {
            name: ADDON_TITLE,
            htmlBody: message.getContent()
          });
    }
  }
}

/**
 * Sends out respondent notification emails.
 *
 * @param {FormResponse} response FormResponse object of the event
 *      that triggered this notification
 */
function sendRespondentNotification(response) {
  var form = FormApp.getActiveForm();
  var settings = PropertiesService.getDocumentProperties();
  var emailId = settings.getProperty('respondentEmailItemId');
  var emailItem = form.getItemById(parseInt(emailId));
  var respondentEmail = response.getResponseForItem(emailItem)
      .getResponse();
  if (respondentEmail) {
    var template =
        HtmlService.createTemplateFromFile('RespondentNotification');
    template.paragraphs = settings.getProperty('responseText').split('\n');
    template.notice = NOTICE;
    var message = template.evaluate();
    MailApp.sendEmail(respondentEmail,
        settings.getProperty('responseSubject'),
        message.getContent(), {
          name: form.getTitle(),
            htmlBody: message.getContent()
        });
  }
}

sidebar.html

forms/notifications/sidebar.html

View on GitHub

<!DOCTYPE html>
<html>
  <head>
    <base target="_top">
    <link rel="stylesheet" href="https://ssl.gstatic.com/docs/script/css/add-ons1.css">
    <!-- The CSS package above applies Google styling to buttons and other elements. -->
    <style>
    .branding-below {
      bottom: 54px;
      top: 0;
    }
    .branding-text {
      left: 7px;
      position: relative;
      top: 3px;
    }
    .logo {
      vertical-align: middle;
    }
    .width-100 {
      width: 100%;
      box-sizing: border-box;
      -webkit-box-sizing: border-box;
      -moz-box-sizing: border-box;
    }
    label {
      font-weight: bold;
    }
    #creator-options,
    #respondent-options {
      background-color: #eee;
      border-color: #eee;
      border-width: 5px;
      border-style: solid;
      display: none;
    }
    #creator-email,
    #respondent-email,
    #button-bar,
    #submit-subject {
      margin-bottom: 10px;
    }

    #response-step {
      display: inline;
    }
    </style>
  </head>
  <body>
    <div class="sidebar branding-below">
      <form>
        <div class="block">
          <input type="checkbox" id="creator-notify">
          <label for="creator-notify">Notify me</label>
        </div>
        <div class="block form-group" id="creator-options">
          <label for="creator-email">
            My email addresses (comma-separated)
          </label>
          <input type="text" class="width-100" id="creator-email">
          <label for="response-step">Send notifications after every</label>
          <input type="number" id="response-step" value="10"
              min="1" max="99999"> responses (default 10)
        </div>

        <div class="block">
          <input type="checkbox" id="respondent-notify">
          <label for="respondent-notify">Notify respondents</label>
        </div>
        <div class="block form-group" id="respondent-options">
          <label for="respondent-email">
            Which question asks for their email?
          </label>
          <select class="width-100" id="respondent-email"></select>
          <label for="submit-subject">
            Notification email subject:
          </label>
          <input type="text" class="width-100" id="submit-subject">
          <label for="submit-notice">Notification email body:</label>
          <textarea rows="8" cols="40" id="submit-notice"
              class="width-100"></textarea>
        </div>

        <div class="block" id="button-bar">
          <button class="action" id="save-settings">Save</button>
        </div>
      </form>
    </div>

    <div class="sidebar bottom">
      <img alt="Add-on logo" class="logo" width="25"
          src="https://g-suite-documentation-images.firebaseapp.com/images/newFormNotificationsicon.png">
      <span class="gray branding-text">Form Notifications by Google</span>
    </div>

    <script src="//ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js">
    </script>
    <script>
      /**
       * On document load, assign required handlers to each element,
       * and attempt to load any saved settings.
       */
      $(function() {
        $('#save-settings').click(saveSettingsToServer);
        $('#creator-notify').click(toggleCreatorNotify);
        $('#respondent-notify').click(toggleRespondentNotify);
        $('#response-step').change(validateNumber);
        google.script.run
           .withSuccessHandler(loadSettings)
           .withFailureHandler(showStatus)
           .withUserObject($('#button-bar').get())
           .getSettings();
      });

      /**
       * Callback function that populates the notification options using
       * previously saved values.
       *
       * @param {Object} settings The saved settings from the client.
       */
      function loadSettings(settings) {
        $('#creator-email').val(settings.creatorEmail);
        $('#response-step').val(!settings.responseStep ?
           10 : settings.responseStep);
        $('#submit-subject').val(!settings.responseSubject ?
           'Thank you for filling out our form!' :
           settings.responseSubject);
        $('#submit-notice').val(!settings.responseText ?
           'Thank you for responding to our form!' :
           settings.responseText);

        if (settings.creatorNotify === 'true') {
          $('#creator-notify').prop('checked', true);
          $('#creator-options').show();
        }

        if (settings.respondentNotify === 'true') {
          $('#respondent-notify').prop('checked', true);
          $('#respondent-options').show();
        }

        // Fill the respondent email select box with the
        // titles given to the form's text Items. Also include
        // the form Item IDs as values so that they can be
        // easily recovered during the Save operation.
        for (var i = 0; i < settings.textItems.length; i++) {
          var option = $('<option>').attr('value', settings.textItems[i]['id'])
              .text(settings.textItems[i]['title']);
          $('#respondent-email').append(option);
        }
        $('#respondent-email').val(settings.respondentEmailItemId);
      }

      /**
       * Toggles the visibility of the form creator notification options.
       */
      function toggleCreatorNotify() {
        $('#status').remove();
        if ($('#creator-notify').is(':checked')) {
          $('#creator-options').show();
        } else {
          $('#creator-options').hide();
        }
      }

      /**
       * Toggles the visibility of the form sumbitter notification options.
       */
      function toggleRespondentNotify() {
        $('#status').remove();
        if($('#respondent-notify').is(':checked')) {
          $('#respondent-options').show();
        } else {
          $('#respondent-options').hide();
        }
      }

      /**
       * Ensures that the entered step is a number between 1
       * and 99999, inclusive.
       */
      function validateNumber() {
        var value = $('#response-step').val();
        if (!value) {
          $('#response-step').val(10);
        } else if (value < 1) {
          $('#response-step').val(1);
        } else if (value > 99999) {
          $('#response-step').val(99999);
        }
      }

      /**
       * Collects the options specified in the add-on sidebar and sends them to
       * be saved as Properties on the server.
       */
      function saveSettingsToServer() {
        this.disabled = true;
        $('#status').remove();
        var creatorNotify = $('#creator-notify').is(':checked');
        var respondentNotify = $('#respondent-notify').is(':checked');
        var settings = {
          'creatorNotify': creatorNotify,
          'respondentNotify': respondentNotify
        };

        // Only save creator options if notify is turned on
        if (creatorNotify) {
          settings.responseStep = $('#response-step').val();
          settings.creatorEmail = $('#creator-email').val().trim();

          // Abort save if entered email is blank
          if (!settings.creatorEmail) {
            showStatus('Enter an owner email', $('#button-bar'));
            this.disabled = false;
            return;
          }
        }

        // Only save respondent options if notify is turned on
        if (respondentNotify) {
          settings.respondentEmailItemId = $('#respondent-email').val();
          settings.responseSubject = $('#submit-subject').val();
          settings.responseText = $('#submit-notice').val();
        }

        // Save the settings on the server
        google.script.run
            .withSuccessHandler(
              function(msg, element) {
                showStatus('Saved settings', $('#button-bar'));
                element.disabled = false;
              })
            .withFailureHandler(
              function(msg, element) {
                showStatus(msg, $('#button-bar'));
                element.disabled = false;
              })
            .withUserObject(this)
            .saveSettings(settings);
      }

      /**
       * Inserts a div that contains an status message after a given element.
       *
       * @param {String} msg The status message to display.
       * @param {Object} element The element after which to display the Status.
       */
      function showStatus(msg, element) {
         var div = $('<div>')
             .attr('id', 'status')
             .attr('class','error')
             .text(msg);
        $(element).after(div);
      }
    </script>
  </body>
</html>

about.html

forms/notifications/about.html

View on GitHub

<!DOCTYPE html>
<html>
  <head>
    <base target="_top">
    <link rel="stylesheet" href="https://ssl.gstatic.com/docs/script/css/add-ons1.css">
    <!-- The CSS package above applies Google styling to buttons and other elements. -->
  </head>
  <body>
    <div>
      <p>
      <i>Form Notifications</i> was created as an sample add-on, and is meant
      for demonstration purposes only. It should not be used for complex or
      important workflows.
      </p>
      <p>
      The number of notifications this add-on produces are limited by the owner's
      available email quota; it will not send email notifications if the owner's
      daily email quota has been exceeded. Collaborators using this add-on on the
      same form will be able to adjust the notification settings, but will not be
      able to disable the notification triggers set by other collaborators.
      </p>
    </div>
  </body>
</html>

5. Create three more HTML files: authorizationEmail.html , creatorNotification.html, and respondentNotification.html. Replace the content of those files with the following content, respectively:

authorizationEmail.html

forms/notifications/authorizationEmail.html

View on GitHub

<p>The Google Forms add-on <i>Form Notifications</i> is set to run automatically
whenever a form is submitted. The add-on was recently updated and it needs you
to re-authorize it to run on your behalf.</p>

<p>The add-on's automatic functions are temporarily disabled until you
re-authorize the add-on. You can accomplish this by opening one of the forms
using the add-on and running the add-on through the menu. Alternatively, you can
click this link to approve authorization directly:</p>

<p><a href="<?= url ?>">Click here</a> to re-authorize the add-on.</p>

<p>This notification email will be sent to you at most once per day until the
add-on is re-authorized.</p>

<hr>

<p style="font-size:80%">This automatic message was sent to you via the <i>Form
Notifications</i> add-on for Google Forms.
<?= notice ?></p>

creatorNotification.html

forms/notifications/creatorNotification.html

View on GitHub

<p><i>Form Notifications</i> (a Google Forms add-on) has detected that the form
titled <a href="<?= formUrl?>"><b><?= title ?></b></a> has received
<?= responses ?> responses so far.</p>

<p><a href="<?= sheet ?>">Response sheet</a></p>
<p><a href="<?= summary ?>">Summary of form responses</a></p>

<p>You are receiving this email because an editor of this form configured
<i>Form Notifications</i> to alert you every time this form receives
<b><?= responseStep ?></b> responses.</p>

<p>To change this setting, or to stop receiving these notifications, have the
form owner or editors open the form and adjust the <i>Form Notifications</i>
add-on configuration via the "Configure notifications" menu item.</p>

<hr>

<p style="font-size:80%">This automatic message was sent to you via the <i>Form
Notifications</i> add-on for Google Forms.
<?= notice ?></p>

respondentNotification.html

forms/notifications/respondentNotification.html

View on GitHub

<? for (var i = 0; i < paragraphs.length; i++) { ?>
  <p><?= paragraphs[i] ?></p>
<? } ?>

<hr>

<p style="font-size:80%">This automatic message was sent to you via the <i>Form
Notifications</i> add-on for Google Forms.
<?= notice ?></p>

6. Select the menu item File > Save all. Name your new script "Form Notifications Quickstart" and click OK. (The script's name is shown to end users in several places, including the authorization dialog.)

When you have completed this process, you will have a project with 1 script file and 5 HTML files.

Try it out

1. Switch back to your form. Using the Add item select box, add a text question to your form. Under Question Title, enter 'Email Address' and click Done. You can create other form items if you like.
2. After a few seconds, a Form Notifications Quickstart sub-menu will appear under the Add-ons menu. (If you chose a different name for your script, that name appears instead.) Click Add-ons > Form Notifications Quickstart, and in the resulting dialog click Configure notifications.
3. A dialog box requesting script authorization appears. Click Continue.
4. The add-on sidebar then appears. To test it, click the Notify me check box and enter your email address. Also set the Send notifications after box to '1'. Click Save.
5. Click Preview so that you can submit a response. From here, enter some information into the form elements and click Submit. If you have done everything correctly, the add-on emails you a short notification saying someone has responded to your form. Had you not changed the Send notifications after every box, the add-on would have waited until the form had 10 submissions (the default) before emailing you a notice.
6. To test the respondent notifications, go back to the sidebar and click the Notify respondents checkbox. The first select box lists the question titles for each text question in your form. Choose the question you labeled 'Email Address'. If the 'Email Address' option does not appear, make sure you've added a text item to your form named 'Email Address' (as stated in Step 1), and reopen the sidebar by clicking Add-ons > Form Notifications Quickstart, and in the resulting dialog clicking Configure notifications.
7. Change the text in the Notification email body text area to say what you what to tell the respondents to your form.
8. Go back to the form, fill out another submission and click Submit. If you have done everything correctly, two emails should be sent this time—one to the form creator and one to the form respondent. The form creator email address is the one you entered into the sidebar directly; the form respondent email address is what the respondent supplied in the 'Email Address' question.

Publish

Since this is an example add-on, our tutorial ends here. If you were developing a real add-on, the last step would be to publish it for other people to find and install.

Learn more

To continue learning about how to extend Google Docs with Apps Script, take a look at the following resources:

• Add-on documentation
• Forms Service Reference