Google App Script - Download files from Google Drive by the one time download method [File is Public for 1 Minutes and automatically Unshared]

appsscript.json

{
  "timeZone": "America/Chicago",
  "dependencies": {},
  "exceptionLogging": "STACKDRIVER",
  "runtimeVersion": "V8"
}

info.md

When downloading a file from Google Drive, login credentials and an access token are generally required. However, if you want to download a file without authorization in a simple situation, the file must be publicly shared. Unfortunately, files cannot always be shared publicly due to various restrictions.

In this method, the file is made publicly accessible but only for one minute. Usually once a publicly shared file begins downloading from Google Drive, the download continues even if the file's permissions are changed back to private during the process. This approach effectively creates a "pseudo one-time download."

YOU MUST GET A API KEY - https://developers.google.com/maps/documentation/javascript/get-api-key

OneTimeDownloadFromGoogleDrive.gs

function deletePermission() {
  const forTrigger = "deletePermission";
  const id = CacheService.getScriptCache().get("id");
  const triggers = ScriptApp.getProjectTriggers();
  triggers.forEach(function(e) {
    if (e.getHandlerFunction() == forTrigger) ScriptApp.deleteTrigger(e);
  });
  const file = DriveApp.getFileById(id);
  file.setSharing(DriveApp.Access.PRIVATE, DriveApp.Permission.NONE);
}

function checkTrigger(forTrigger) {
  const triggers = ScriptApp.getProjectTriggers();
  for (var i = 0; i < triggers.length; i++) {
    if (triggers[i].getHandlerFunction() == forTrigger) {
      return false;
    }
  }
  return true;
}

function doGet(e) {
  const key = "###"; // <--- API key. This is also used for checking the user.
  
  const forTrigger = "deletePermission";
  var res = "";
  if (checkTrigger(forTrigger)) {
    if ("id" in e.parameter && e.parameter.key == key) {
      const id = e.parameter.id;
      CacheService.getScriptCache().put("id", id, 180);
      const file = DriveApp.getFileById(id);
      file.setSharing(DriveApp.Access.ANYONE_WITH_LINK, DriveApp.Permission.VIEW);
      var d = new Date();
      d.setMinutes(d.getMinutes() + 1);
      ScriptApp.newTrigger(forTrigger).timeBased().at(d).create();
      res = "https://www.googleapis.com/drive/v3/files/" + id + "?alt=media&key=" + e.parameter.key;
    } else {
      res = "unavailable";
    }
  } else {
    res = "unavailable";
  }
  return ContentService.createTextOutput(res);
}