Google Forms Editor add-on quickstart

This quickstart creates a Google Forms Editor add-on that uses triggers to send an email when a user responds to the form.

Objectives

  • Set up the script.
  • Run the script.

Prerequisites

To use this sample, you need the following prerequisites:

  • A Google Account (Google Workspace accounts might require administrator approval).
  • A web browser with access to the internet.

Set up the script

  1. Create a Google Forms form at forms.new.
  2. Click More > Script editor.
  3. Click Untitled project.
  4. Rename the Apps Script project Forms notifications and click Rename.
  5. Click Add a file > HTML. Name the file sidebar.
  6. Repeat step 5 to create 4 more HTML files named about, authorizationEmail, creatorNotification, and respondentNotification. When you're done you should have 1 script file and 5 HTML files.
  7. Replace the contents of each file with the following corresponding code, then click Save Save icon.

    code.gs

    forms/notifications/notification.gs
    /**
     * @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.
     */
    const ADDON_TITLE = 'Form Notifications';
    
    /**
     * A global constant 'notice' text to include with each email
     * notification.
     */
    const 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) {
      try {
        FormApp.getUi()
            .createAddonMenu()
            .addItem('Configure notifications', 'showSidebar')
            .addItem('About', 'showAbout')
            .addToUi();
      } catch (e) {
        // TODO (Developer) - Handle exception
        console.log('Failed with error: %s', e.error);
      }
    }
    
    /**
     * 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() {
      try {
        const ui = HtmlService.createHtmlOutputFromFile('sidebar')
            .setTitle('Form Notifications');
        FormApp.getUi().showSidebar(ui);
      } catch (e) {
        // TODO (Developer) - Handle exception
        console.log('Failed with error: %s', e.error);
      }
    }
    
    /**
     * Opens a purely-informational dialog in the form explaining details about
     * this add-on.
     */
    function showAbout() {
      try {
        const ui = HtmlService.createHtmlOutputFromFile('about')
            .setWidth(420)
            .setHeight(270);
        FormApp.getUi().showModalDialog(ui, 'About Form Notifications');
      } catch (e) {
        // TODO (Developer) - Handle exception
        console.log('Failed with error: %s', e.error);
      }
    }
    
    /**
     * 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) {
      try {
        PropertiesService.getDocumentProperties().setProperties(settings);
        adjustFormSubmitTrigger();
      } catch (e) {
        // TODO (Developer) - Handle exception
        console.log('Failed with error: %s', e.error);
      }
    }
    
    /**
     * 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() {
      try {
        const 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.
        const form = FormApp.getActiveForm();
        const textItems = form.getItems(FormApp.ItemType.TEXT);
    
        settings.textItems = [];
        for (let i = 0; i < textItems.length; i++) {
          settings.textItems.push({
            title: textItems[i].getTitle(),
            id: textItems[i].getId()
          });
        }
        return settings;
      } catch (e) {
        // TODO (Developer) - Handle exception
        console.log('Failed with error: %s', e.error);
      }
    }
    
    /**
     * Adjust the onFormSubmit trigger based on user's requests.
     */
    function adjustFormSubmitTrigger() {
      try {
        const form = FormApp.getActiveForm();
        const triggers = ScriptApp.getUserTriggers(form);
        const settings = PropertiesService.getDocumentProperties();
        const triggerNeeded =
          settings.getProperty('creatorNotify') === 'true' ||
          settings.getProperty('respondentNotify') === 'true';
    
        // Create a new trigger if required; delete existing trigger
        // if it is not needed.
        let existingTrigger = null;
        for (let i = 0; i < triggers.length; i++) {
          if (triggers[i].getEventType() === ScriptApp.EventType.ON_FORM_SUBMIT) {
            existingTrigger = triggers[i];
            break;
          }
        }
        if (triggerNeeded && !existingTrigger) {
          const trigger = ScriptApp.newTrigger('respondToFormSubmit')
              .forForm(form)
              .onFormSubmit()
              .create();
        } else if (!triggerNeeded && existingTrigger) {
          ScriptApp.deleteTrigger(existingTrigger);
        }
      } catch (e) {
        // TODO (Developer) - Handle exception
        console.log('Failed with error: %s', e.error);
      }
    }
    
    /**
     * 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) {
      try {
        const settings = PropertiesService.getDocumentProperties();
        const 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);
          }
        }
      } catch (e) {
        // TODO (Developer) - Handle exception
        console.log('Failed with error: %s', e.error);
      }
    }
    
    
    /**
     * 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() {
      try {
        const settings = PropertiesService.getDocumentProperties();
        const authInfo = ScriptApp.getAuthorizationInfo(ScriptApp.AuthMode.FULL);
        const lastAuthEmailDate = settings.getProperty('lastAuthEmailDate');
        const today = new Date().toDateString();
        if (lastAuthEmailDate !== today) {
          if (MailApp.getRemainingDailyQuota() > 0) {
            const template =
              HtmlService.createTemplateFromFile('authorizationEmail');
            template.url = authInfo.getAuthorizationUrl();
            template.notice = NOTICE;
            const message = template.evaluate();
            MailApp.sendEmail(Session.getEffectiveUser().getEmail(),
                'Authorization Required',
                message.getContent(), {
                  name: ADDON_TITLE,
                  htmlBody: message.getContent()
                });
          }
          settings.setProperty('lastAuthEmailDate', today);
        }
      } catch (e) {
        // TODO (Developer) - Handle exception
        console.log('Failed with error: %s', e.error);
      }
    }
    
    /**
     * Sends out creator notification email(s) if the current number
     * of form responses is an even multiple of the response step
     * setting.
     */
    function sendCreatorNotification() {
      try {
        const form = FormApp.getActiveForm();
        const settings = PropertiesService.getDocumentProperties();
        let 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) {
          const addresses = settings.getProperty('creatorEmail').split(',');
          if (MailApp.getRemainingDailyQuota() > addresses.length) {
            const template =
              HtmlService.createTemplateFromFile('creatorNotification');
            template.summary = form.getSummaryUrl();
            template.responses = form.getResponses().length;
            template.title = form.getTitle();
            template.responseStep = responseStep;
            template.formUrl = form.getEditUrl();
            template.notice = NOTICE;
            const message = template.evaluate();
            MailApp.sendEmail(settings.getProperty('creatorEmail'),
                form.getTitle() + ': Form submissions detected',
                message.getContent(), {
                  name: ADDON_TITLE,
                  htmlBody: message.getContent()
                });
          }
        }
      } catch (e) {
        // TODO (Developer) - Handle exception
        console.log('Failed with error: %s', e.error);
      }
    }
    
    /**
     * Sends out respondent notification emails.
     *
     * @param {FormResponse} response FormResponse object of the event
     *      that triggered this notification
     */
    function sendRespondentNotification(response) {
      try {
        const form = FormApp.getActiveForm();
        const settings = PropertiesService.getDocumentProperties();
        const emailId = settings.getProperty('respondentEmailItemId');
        const emailItem = form.getItemById(parseInt(emailId));
        const respondentEmail = response.getResponseForItem(emailItem)
            .getResponse();
        if (respondentEmail) {
          const template =
            HtmlService.createTemplateFromFile('respondentNotification');
          template.paragraphs = settings.getProperty('responseText').split('\n');
          template.notice = NOTICE;
          const message = template.evaluate();
          MailApp.sendEmail(respondentEmail,
              settings.getProperty('responseSubject'),
              message.getContent(), {
                name: form.getTitle(),
                htmlBody: message.getContent()
              });
        }
      } catch (e) {
        // TODO (Developer) - Handle exception
        console.log('Failed with error: %s', e.error);
      }
    }

    sidebar.html

    forms/notifications/sidebar.html
    <!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
    <!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>

    authorizationEmail.html

    forms/notifications/authorizationEmail.html
    <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
    <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="<?= 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
    <? 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>

Run the script

  1. Switch back to your form and refresh the page.
  2. Add a short answer text question to your form. In Untitled question, enter Email Address. Optionally, you can create other form questions.
  3. Click add-ons > Form notifications. It might take several seconds for add-ons to appear.
  4. In the dialog, click Configure notifications.
  5. When prompted, authorize the add-on.
  6. Again, click add-ons > Form notifications > Configure notifications.
  7. In the add-on, check the Notify me box and enter your email address.
  8. For Send notifications after every, enter 1.
  9. Click Save.
  10. To submit a response, click Preview
  11. Fill out the form and click Submit.
  12. Check your email for a notification.

Next steps