Advanced Gmail Service

  • The Advanced Gmail service in Apps Script lets you use the Gmail API to interact with your mailbox, offering more features than the built-in service.

  • This advanced service requires enabling before use and provides access to detailed information about threads, messages, and labels.

  • You can utilize the provided sample code snippets to list label information, inbox snippets, and recent history within your Gmail account.

  • The Gmail API might limit data returned in list requests for performance, requiring follow-up 'get' requests for detailed information.

  • For comprehensive details, refer to the reference documentation, support guide, and sample code on GitHub.

The Advanced Gmail service allows you to use the Gmail API in Apps Script. Much like Apps Script's built-in Gmail service, this API allows scripts to find and modify threads, messages, and labels in a Gmail mailbox. In most cases, the built-in service is easier to use, but this advanced service provides a few extra features and access to more detailed information about Gmail content.

Reference

For detailed information on this service, see the reference documentation for the Gmail API. Like all advanced services in Apps Script, the advanced Gmail service uses the same objects, methods, and parameters as the public API. For more information, see How method signatures are determined.

To report issues and find other support, see the Gmail support guide.

Sample code

The sample code below uses version 1 of the API.

List label information

The following example demonstrates how to list all the user's label information. This includes the label name, type, ID and visibility settings.

advanced/gmail.gs
/**
 * Lists the user's labels, including name, type,
 * ID and visibility information.
 */
function listLabelInfo() {
  try {
    const response =
      Gmail.Users.Labels.list('me');
    for (let i = 0; i < response.labels.length; i++) {
      const label = response.labels[i];
      console.log(JSON.stringify(label));
    }
  } catch (err) {
    console.log(err);
  }
}

List inbox snippets

The following example demonstrates how to list text snippets associated with each thread in the user's Inbox. Notice the use of page tokens to access the full list of results.

advanced/gmail.gs
/**
 * Lists, for each thread in the user's Inbox, a
 * snippet associated with that thread.
 */
function listInboxSnippets() {
  try {
    let pageToken;
    do {
      const threadList = Gmail.Users.Threads.list('me', {
        q: 'label:inbox',
        pageToken: pageToken
      });
      if (threadList.threads && threadList.threads.length > 0) {
        threadList.threads.forEach(function (thread) {
          console.log('Snippet: %s', thread.snippet);
        });
      }
      pageToken = threadList.nextPageToken;
    } while (pageToken);
  } catch (err) {
    console.log(err);
  }
}

List recent history

The following example demonstrates how to log recent activity history. Specifically, this example recovers the history record ID associated with the user's most recently sent message, and then logs the message IDs of every message that has changed since that time. Each changed message is only logged once, no matter how many change events are in the history records. Notice the use of page tokens to access the full list of results.

advanced/gmail.gs
/**
 * Gets a history record ID associated with the most
 * recently sent message, then logs all the message IDs
 * that have changed since that message was sent.
 */
function logRecentHistory() {
  try {
    // Get the history ID associated with the most recent
    // sent message.
    const sent = Gmail.Users.Threads.list('me', {
      q: 'label:sent',
      maxResults: 1
    });
    if (!sent.threads || !sent.threads[0]) {
      console.log('No sent threads found.');
      return;
    }
    const historyId = sent.threads[0].historyId;

    // Log the ID of each message changed since the most
    // recent message was sent.
    let pageToken;
    const changed = [];
    do {
      const recordList = Gmail.Users.History.list('me', {
        startHistoryId: historyId,
        pageToken: pageToken
      });
      const history = recordList.history;
      if (history && history.length > 0) {
        history.forEach(function (record) {
          record.messages.forEach(function (message) {
            if (changed.indexOf(message.id) === -1) {
              changed.push(message.id);
            }
          });
        });
      }
      pageToken = recordList.nextPageToken;
    } while (pageToken);

    changed.forEach(function (id) {
      console.log('Message Changed: %s', id);
    });
  } catch (err) {
    console.log(err);
  }
}

List messages

The following example demonstrates how to list the Gmail user's unread messages.

advanced/gmail.gs
/**
 * Lists unread messages in the user's inbox using the advanced Gmail service.
 */
function listMessages() {
  // The special value 'me' indicates the authenticated user.
  const userId = 'me';

  // Define optional parameters for the request.
  const options = {
    maxResults: 10, // Limit the number of messages returned.
    q: 'is:unread', // Search for unread messages.
  };

  try {
    // Call the Gmail.Users.Messages.list method.
    const response = Gmail.Users.Messages.list(userId, options);
    const messages = response.messages;
    console.log('Unread Messages:');

    for (const message of messages) {
      console.log(`- Message ID: ${message.id}`);
    }
  } catch (err) {
    // Log any errors to the Apps Script execution log.
    console.log(`Failed with error: ${err.message}`);
  }
}