Spreadsheet Updates Automatically When Email Is Received, (pub/sub) But with Wrong information

I set up my first Pub/Sub on Google Cloud Platform that uses Gmail API to update my spreadsheet each time I receive an email

(More information on how to do this in my previous question)

However, the below doPost function returns something like this on my spreadsheet:
"8/4/2023 10:01:59", "8011555761044464", "{"emailAddress":"myemail@gmail.com","historyId":37309620}"

I am still quite new, but I'd like the spreadsheet to have the sender's information and the subject line. How can I improve my script?

// ************************* POST *************************

function doPost (e) {

const message = JSON.parse(e.postData.getDataAsString()).message;
const data = Utilities.newBlob(Utilities.base64Decode(message.data)).getDataAsString();
const ss = SpreadsheetApp.openById("MYSHEET").getSheetByName("Borghers Emails");
ss.appendRow([new Date(), message.message_id, data]);
return 200;

};

// ************************* ENROLL EMAIL *************************

function enrollEmail() {

try {

  const watchRes = {
    labelIds: ["INBOX"],
    labelFilterAction: "include",
    topicName: "projects/myproject/topics/gmailTrigger"
  };

  const response = Gmail.Users.watch(watchRes, "me");
  console.log(response);


} catch (error) {
  console.log(error);
}

};

EDIT: HERE IS THE UPDATED CODE This actually works, thank you Tanaike! However, I think there is a miscommunication between the Pub/Sub and my script because when I send one test email, the spreadsheet will go into an infinite loop where it is updating the sheet and will not stop. I am uncertain how to communicate with the Pub/Sub to ensure only ONE message occurs at a time. See below for my script and the result on my sheet:

function doPost(e) {

  const message = JSON.parse(e.postData.getDataAsString()).message;
  const data = JSON.parse(Utilities.newBlob(Utilities.base64Decode(message.data)).getDataAsString());

  const { historyId } = data;
  const { history } = Gmail.Users.History.list("me", { startHistoryId: historyId });

  if (history.length > 0) {
    const messageId = history[0].messages[0].id;
    const msg = GmailApp.getMessageById(messageId);
    const ss = SpreadsheetApp.openById("MYSHEET").getSheetByName("Email Log");
    ss.appendRow([new Date(), messageId, msg.getFrom(), msg.getSubject()]);
  }

  return ContentService.createTextOutput("ok");

}

I believe your goal is as follows.

• You have already finished setting for pushing to your Web Apps with pub/sub when an email is received.
• You want to retrieve the email address of the email and the email title by modifying your script.

In this case, how about the following modification?

Modified script:

Please enable Gmail API at Advanced Google services.

function doPost(e) {
  const message = JSON.parse(e.postData.contents).message;
  const data = JSON.parse(Utilities.newBlob(Utilities.base64Decode(message.data)).getDataAsString());
  const { historyId } = data;
  const { history } = Gmail.Users.History.list("me", { startHistoryId: historyId });
  if (history.length > 0) {
    const messageId = history[0].messages[0].id;
    const msg = GmailApp.getMessageById(messageId);
    const ss = SpreadsheetApp.openById("MYSHEET").getSheetByName("Borghers Emails");
    ss.appendRow([new Date(), messageId, msg.getFrom(), msg.getSubject()]);
  }
  return ContentService.createTextOutput("ok");
}

• In this modified script, when an email is received, doPost is run with the event object from pub/sub. And, the history ID is retrieved from the event object. And then, the message ID is retrieved from the latest history ID. And the message ID, from, and the message title are retrieved, and those values are appended to the sheet "Borghers Emails".

• In this case, message.message_id in your script is not the same as the message ID of the email. That is pub/sub message ID. Please be careful about this.

Note:

• When you modified the Google Apps Script of Web Apps, please modify the deployment as a new version. By this, the modified script is reflected in Web Apps. Please be careful about this.

• You can see the detail of this in my report "Redeploying Web Apps without Changing URL of Web Apps for new IDE (Author: me)".

Reference:

• Method: users.history.list