google apps script - (Gmail) Sending emails from spreadsheet. How to add signature with image?

Question

Due to the large amount of emails i'm sending with GMAIL i decided to automatize this process using a script and following this tutorial.Tutorial: Sending emails from a Spreadsheet

The "Message" is being generated by another function i created, called prepareEmails.

The problems are the following:

1) How can i tell prepareEmails to add my personal signature? I can't simply copy its text into that function, because my signature contains an image (for which i have the URL), and i want that image to be into the signature.

2) How can i make my signature BOLD?

Thanks everybody

Answer 1

There is an open Issue 2441 requesting the ability to append gmail signatures to email when using the GMailService. Visit and star it to receive updates.

As @wchiquito suggests, you can craft a script to attach images, producing a signature. You can also use HTML tags such as <B></B> to render text in bold, and so on.

Here's a different approach that will instead use a draft email as a template. This way, you can produce your signature with a variety of fonts and images using the online editor, and end up with a capability similar to automatic signature insertion.

The template needs to be saved in your Drafts folder, and it needs to have a tag indicating where the body of emails should go.

Example

function sendWithTemplate() {
  var msgBody = "Test of sending a message using a template with a signature.";
  sendGmailTemplate(Session.getActiveUser().getEmail(), 'test', msgBody );
}

Script

/**
 * Insert the given email body text into an email template, and send
 * it to the indicated recipient. The template is a draft message with
 * the subject "TEMPLATE"; if the template message is not found, an
 * exception will be thrown. The template must contain text indicating
 * where email content should be placed: {BODY}.
 *
 * @param {String} recipient  Email address to send message to.
 * @param {String} subject    Subject line for email.
 * @param {String} body       Email content, may be plain text or HTML.
 * @param {Object} options    (optional) Options as supported by GmailApp.
 *
 * @returns        GmailApp   the Gmail service, useful for chaining
 */
function sendGmailTemplate(recipient, subject, body, options) {
  options = options || {};  // default is no options
  var drafts = GmailApp.getDraftMessages();
  var found = false;
  for (var i=0; i<drafts.length && !found; i++) {
    if (drafts[i].getSubject() == "TEMPLATE") {
      found = true;
      var template = drafts[i];
    }
  }
  if (!found) throw new Error( "TEMPLATE not found in drafts folder" );

  // Generate htmlBody from template, with provided text body
  var imgUpdates = updateInlineImages(template);
  options.htmlBody = imgUpdates.templateBody.replace('{BODY}', body);
  options.attachments = imgUpdates.attachments;
  options.inlineImages = imgUpdates.inlineImages;
  return GmailApp.sendEmail(recipient, subject, body, options);
}


/**
 * This function was adapted from YetAnotherMailMerge by Romain Vaillard.
 * Given a template email message, identify any attachments that are used
 * as inline images in the message, and move them from the attachments list
 * to the inlineImages list, updating the body of the message accordingly.
 *
 * @param   {GmailMessage} template  Message to use as template
 * @returns {Object}                 An object containing the updated 
 *                                   templateBody, attachments and inlineImages.
 */
function updateInlineImages(template) {
  //////////////////////////////////////////////////////////////////////////////
  // Get inline images and make sure they stay as inline images
  //////////////////////////////////////////////////////////////////////////////
  var templateBody = template.getBody();
  var rawContent = template.getRawContent();
  var attachments = template.getAttachments();

  var regMessageId = new RegExp(template.getId(), "g");
  if (templateBody.match(regMessageId) != null) {
    var inlineImages = {};
    var nbrOfImg = templateBody.match(regMessageId).length;
    var imgVars = templateBody.match(/<img[^>]+>/g);
    var imgToReplace = [];
    if(imgVars != null){
      for (var i = 0; i < imgVars.length; i++) {
        if (imgVars[i].search(regMessageId) != -1) {
          var id = imgVars[i].match(/realattid=([^&]+)&/);
          if (id != null) {
            var temp = rawContent.split(id[1])[1];
            temp = temp.substr(temp.lastIndexOf('Content-Type'));
            var imgTitle = temp.match(/name="([^"]+)"/);
            if (imgTitle != null) imgToReplace.push([imgTitle[1], imgVars[i], id[1]]);
          }
        }
      }
    }
    for (var i = 0; i < imgToReplace.length; i++) {
      for (var j = 0; j < attachments.length; j++) {
        if(attachments[j].getName() == imgToReplace[i][0]) {
          inlineImages[imgToReplace[i][2]] = attachments[j].copyBlob();
          attachments.splice(j, 1);
          var newImg = imgToReplace[i][1].replace(/src="[^"]+"/, "src="cid:" + imgToReplace[i][2] + """);
          templateBody = templateBody.replace(imgToReplace[i][1], newImg);
        }
      }
    }
  }
  var updatedTemplate = {
    templateBody: templateBody,
    attachments: attachments,
    inlineImages: inlineImages
  }
  return updatedTemplate;
}

Credit where credit is due: The "Yet Another Mail Merge" script includes code that preserves inline images in emails during a mail merge - I've borrowed from that. Thanks Romain!