gmail add-on

[gsuiter]

I have created the following gmail add-on and am looking for some guidance. The goal is to enable the inbox owner to select several mails and package them into a zip file. The owner can then download or drag and drop the URL to another application. I am facing two problems. The add-on view seems to only be additive for each new email selected. Selecting a previously selected email only shows buttons for emails / files that were selected and created prior. Also, once a file has been removed, it cant be added again. Its as if each mail has its own view or cache of the add-on and I cant figure out how to refresh the view during each event or mail selection.

Also, in addition to the zip button, I want to have a html text view of the URL in the card but cant figure out the refresh sequence to show it, it is currently commented out.

code:

// Function to load the Gmail add-on

function loadAddOn(event) {

  var url = ""

  if (event) {

    var accessToken = event.gmail.accessToken;

    var messageId = event.gmail.messageId;

    GmailApp.setCurrentMessageAccessToken(accessToken);

    var mailMessage = GmailApp.getMessageById(messageId);

    var eml = mailMessage.getRawContent();

    var date = new Date().getTime(); // Get current epoch time

    // Create or get the folder where emails will be stored

    var tempFolder;

    try {

      tempFolder = DriveApp.getFoldersByName('temp').next();

    } catch (e) {

      tempFolder = DriveApp.createFolder('temp');

    }

    // Create a file for the current email in the folder with a unique name

    var messageIdSuffix = messageId.split(':').pop(); // Get the part after the colon

    var fileName = mailMessage.getSubject() + '_' + messageIdSuffix + '.eml'; // Use message ID suffix in the file name

    var emailFile = createUniqueFile(tempFolder, fileName, eml);

  }

  // Retrieve all files in the folder if it exists

  var emailButtons = [];

  if (tempFolder) {

    var files = tempFolder.getFiles();

    // Create buttons for each email file in the folder

    while (files.hasNext()) {

      var file = files.next();

      if (!file.isTrashed() && file.getName().indexOf('.zip') === -1) { // Check if file is not .zip

        var emailId = file.getId();

        var emailSubject = file.getName().replace(/\.eml$/, ''); // Remove extension

        var button = CardService.newTextButton()

          .setText(emailSubject)

          .setOnClickAction(CardService.newAction()

            .setFunctionName('handleEmailSelection')

            .setParameters({ 'emailId': emailId }));

        emailButtons.push(button);

      }

    }

  }

  // Add a button to remove all emails from the folder

  var clearAllButton = CardService.newTextButton()

    .setText('Clear All')

    .setOnClickAction(CardService.newAction().setFunctionName('clearAllEmails'));

  var buttonSet = CardService.newButtonSet();

  for (var i = 0; i < emailButtons.length; i++) {

    buttonSet.addButton(emailButtons[i]);

  }

  buttonSet.addButton(clearAllButton);

  // Check if there are files to create a zip file

  var hasFiles = emailButtons.length > 0;

  // Add a button to produce the zip file when there are files

  if (hasFiles) {

    var zipButton = CardService.newTextButton()

      .setText('Create Zip File')

      .setOnClickAction(CardService.newAction().setFunctionName('createZipFile'));

    buttonSet.addButton(zipButton);

  }

  // Create a section with the button set

  var section = CardService.newCardSection().addWidget(buttonSet);

  // Create a card with the section

  var card = CardService.newCardBuilder()

    .setHeader(CardService.newCardHeader().setTitle('Selected Emails'))

    .addSection(section)

    .build();

  return [card];

}

// Function to create a file with a unique name in the given folder

function createUniqueFile(folder, fileName, content) {

  var existingFiles = folder.getFilesByName(fileName);

  if (existingFiles.hasNext()) {

    // If a file with the same name already exists, return that file

    return existingFiles.next();

  } else {

    // Otherwise, create a new file with the unique name

    return folder.createFile(fileName, content);

  }

}

// Function to handle email selection

function handleEmailSelection(e) {

  // Retrieve the selected email ID from the event parameters

  var emailId = e.parameters.emailId;

  // Get the file by ID and delete it

  var file = DriveApp.getFileById(emailId);

  file.setTrashed(true);

  // Reload the add-on card after handling email selection

  return loadAddOn();

}

// Function to remove all emails from the folder

function clearAllEmails() {

  var tempFolder = DriveApp.getFoldersByName('temp').next();

  var files = tempFolder.getFiles();

  while (files.hasNext()) {

    var file = files.next();

    file.setTrashed(true);

  }

  // Reload the add-on card after clearing all emails

  return loadAddOn();

}

// Function to create a zip file

function createZipFile() {

  var tempFolder = DriveApp.getFoldersByName('temp').next();

  var files = tempFolder.getFiles();

  var blobs = [];

  while (files.hasNext()) {

    blobs.push(files.next().getBlob());

  }

  var zipBlob = Utilities.zip(blobs, 'selected_emails.zip');

  var zipFile = tempFolder.createFile(zipBlob);

  var url = "https://drive.google.com/uc?export=download&id=" + zipFile.getId();

  return CardService.newActionResponseBuilder()

    .setNotification(CardService.newNotification()

      .setType(CardService.NotificationType.INFO)

      .setText('Zip file created.'))

    .setOpenLink(CardService.newOpenLink().setUrl(url))

    //.addSection(CardService.newCardSection()

    //.addWidget(CardService.newTextParagraph().setText("Click <a href="+ url +">here</a> to download .zip")))

    .build();

}

// Entry point for the add-on

function buildAddOn(e) {

  return loadAddOn(e);

}

[gsuiter]

I have made some progress with this but it still does not function well. There are several issues:

1. Once a file has been removed using the button, that email can not be added back as a button or file.
2. After deleting a file, the card updates itself automatically but for the card to update after selecting an email, i must manually click the refresh button.
3. The URL button and hyperlink both take you to a new browser window but dont download the file, you must refresh that browser tab or request the url again for it to actually initiate a download, maybe thats due to google wrapping URL's in its own request service?

I would really appreciate some eyes and feedback on this. Thank you.

// Function to create the homepage card with a list of files from the Google Drive folder

function createHomepageCard() {

  var card = CardService.newCardBuilder()

    .setHeader(CardService.newCardHeader()

      .setTitle('Files in Google Drive Folder')

    )

    .addSection(createFileListWidget())

    .addSection(CardService.newCardSection().addWidget(createRefreshButton()))

    .build();

  return card;

}

// Function to create a widget displaying the list of files from the Google Drive folder

function createFileListWidget() {

  var folder;

  try {

    folder = DriveApp.getFoldersByName('temp').next(); // Get the folder named "temp"

  } catch (e) {

    // If the folder is missing, create it

    folder = DriveApp.createFolder('temp');

  }

  var files = folder.getFiles();

  var buttonSet = CardService.newButtonSet();

  var fileCount = 0;

  var zipFileBlob;

  while (files.hasNext()) {

    var file = files.next();

    var fileName = file.getName();

    var fileId = file.getId();

    if (!fileName.endsWith('.zip')) {

      var fileNameParts = fileName.split('_'); // Split the filename by "_"

      var buttonName = fileNameParts.slice(0, -1).join("_"); // Join all parts except the last one

      var button = CardService.newTextButton()

        .setText(buttonName) // Set the button name to only display the part before the last "_"

        .setOnClickAction(CardService.newAction()

          .setFunctionName('deleteFile')

          .setParameters({ fileId: fileId })

        );

      buttonSet.addButton(button);

    }

    else {

      zipFileBlob = fileId; // Save the file ID of the zip file

    }

    fileCount++;

  }

  // Add a "Clear All" button if there are files present

  if (fileCount > 0) {

    buttonSet.addButton(CardService.newTextButton()

      .setText('Clear All')

      .setOnClickAction(CardService.newAction()

        .setFunctionName('clearAllFiles')

      )

    );

  }

  // Add a "Refresh" button to go back to the root card

  //buttonSet.addButton(createRefreshButton());

  // Add a "Zip Files" button if there are files present

  if (fileCount > 0) {

    buttonSet.addButton(CardService.newTextButton()

      .setText('Zip Files')

      .setOnClickAction(CardService.newAction()

        .setFunctionName('zipFiles')

      )

    );

  }

  var section;

  if (fileCount > 0) {

    section = CardService.newCardSection().addWidget(buttonSet);

    if (zipFileBlob) {

    var downloadWidgets = createDownloadLink(zipFileBlob); // Using the modified createDownloadLink function

    // Extracting the paragraph and hyperlink widgets from the returned object

    var paragraph = downloadWidgets.paragraph;

    var hyperlink = downloadWidgets.hyperlink;

    // Adding the new CardSection containing both the paragraph and hyperlink to the main section

    section.addWidget(hyperlink);

    section.addWidget(paragraph);

    }

  } else {

    section = CardService.newCardSection().addWidget(

      CardService.newTextParagraph().setText('No files found. Please select an email to add files to the queue.')

    );

  }

  return section;

}

// Function to create a hyperlink for the zip file download

function createDownloadLink(blob) {

  var url;

  if (typeof blob === 'string') {

    // If the input is already a file ID, use it directly

    url = "https://drive.google.com/uc?export=download&id=" + blob;

  } else if (blob.getId) {

    // If the input is a Blob object, get its ID

    url = "https://drive.google.com/uc?export=download&id=" + blob.getId();

  } else {

    throw new Error('Invalid input for createDownloadLink function.');

  }

 

  // Construct HTML string for the link

  var html = "Click <a href='" + url + "'>here</a> to download .zip";

  // Create a paragraph widget with the HTML

  var paragraph = CardService.newTextParagraph().setText(html);

  var hyperlink = CardService.newTextButton()

    .setText('Download Zip File')

    .setOpenLink(CardService.newOpenLink().setUrl(url));

 

  // Return an object containing both paragraph and hyperlink

  return {

    paragraph: paragraph,

    hyperlink: hyperlink

  };

  }

// Function to create a zip file and provide a link to Google Drive

function createZipFile() {

  var folder = DriveApp.getFoldersByName('temp').next(); // Get the folder named "temp"

  // Check if there's an existing zip file and delete it

  var existingZipFiles = folder.getFilesByName('selected_files.zip');

  while (existingZipFiles.hasNext()) {

    var existingZipFile = existingZipFiles.next();

    existingZipFile.setTrashed(true);

  }

  var files = folder.getFiles();

  var blobs = [];

  while (files.hasNext()) {

    var file = files.next();

    if (!file.getName().endsWith('.zip')) {

      blobs.push(file.getBlob());

    }

  }

  var zipBlob = Utilities.zip(blobs, 'selected_files.zip');

  var zipFile = folder.createFile(zipBlob);

  // Refresh the card after creating the zip file

  var updatedCard = createHomepageCard();

  return CardService.newActionResponseBuilder()

    .setNavigation(CardService.newNavigation().updateCard(updatedCard))

    .setNotification(CardService.newNotification()

      .setType(CardService.NotificationType.INFO)

      .setText('Zip file created.'))

    .build();

}

// Function to handle zipping files when the "Zip Files" button is clicked

function zipFiles() {

  return createZipFile();

}

// Function to handle deleting a file when its button is clicked

function deleteFile(e) {

  var fileId = e.parameters.fileId;

  var file = DriveApp.getFileById(fileId);

  file.setTrashed(true);

  // Delete any existing zip file

  deleteExistingZipFile();

  // Refresh the card after deleting the file

  var updatedCard = createHomepageCard();

  return CardService.newActionResponseBuilder()

    .setNavigation(CardService.newNavigation().updateCard(updatedCard))

    .build();

}

// Function to handle clearing all files when the "Clear All" button is clicked

function clearAllFiles() {

  var folder = DriveApp.getFoldersByName('temp').next(); // Get the folder named "temp"

  var files = folder.getFiles();

  while (files.hasNext()) {

    var file = files.next();

    file.setTrashed(true);

  }

  // Refresh the card after clearing all files

  var updatedCard = createHomepageCard();

  return CardService.newActionResponseBuilder()

    .setNavigation(CardService.newNavigation().updateCard(updatedCard))

    .build();

}

// Function to go back to the root card (refresh)

function gotoRootCard() {

  var nav = CardService.newNavigation()

    .popToRoot()

    .updateCard(onHomepage());

 

  return CardService.newActionResponseBuilder()

    .setNavigation(nav)

    .build();        

}

// Function to create a refresh button

function createRefreshButton() {

  return CardService.newTextButton()

    .setText('Refresh')

    .setOnClickAction(CardService.newAction()

      .setFunctionName('gotoRootCard')

    );

}

// Function to handle the event when an email is selected in the inbox

function onEmailSelected(event) {

  var messageId = event.gmail.messageId;

  var mailMessage = GmailApp.getMessageById(messageId);

  var subject = mailMessage.getSubject();

  var body = mailMessage.getRawContent();

  var messageIdSuffix = messageId.split(':').pop(); // Get the part after the colon

  // Check if a file with the same name already exists

  var folder = DriveApp.getFoldersByName('temp').next(); // Get the folder named "temp"

  var existingFiles = folder.getFilesByName(subject + "_" + messageIdSuffix + ".eml");

  // If a file with the same name already exists, skip the creation process

  if (existingFiles.hasNext()) {

    return;

  }

  // Create a .eml file in the Google Drive directory

  var emlFile = folder.createFile(subject + "_" + messageIdSuffix + ".eml", body);

  // Refresh the homepage card to display the new file button

  return CardService.newActionResponseBuilder()

    .setStateChanged(true) // Indicate that the state of the card has changed

    .setNavigation(CardService.newNavigation().popToRoot()) // Navigate back to the root card

    .build();

}

// Function to handle the event when the add-on is loaded

function onHomepage(e) {

  return createHomepageCard();

}

// Entry point for the add-on

function buildAddOn(e) {

  var accessToken = e.messageMetadata.accessToken;

  var authorized = GmailApp.getUserInfo(accessToken).isCurrentUser;

  if (!authorized) {

    throw new Error('Access denied: Not authorized.');

  }

  // Set up event handler for email selection

  GmailApp.setCurrentMessageAccessToken(accessToken);

  return createHomepageCard();

}

// Function to delete any existing zip file

function deleteExistingZipFile() {

  var folder = DriveApp.getFoldersByName('temp').next(); // Get the folder named "temp"

  var existingZipFiles = folder.getFilesByName('selected_files.zip');

  while (existingZipFiles.hasNext()) {

    var existingZipFile = existingZipFiles.next();

    existingZipFile.setTrashed(true);

  }

}

[Ed Robinson]

Hi Gsuiter,

probably the reason you're not getting a ton of help is the complexity for people in the community to set up the project themselves in their own environments and see whats going on.

I wonder if it is possible to create a shareable spreadsheet/document/project that demonstrates the issue?