当文档即将过期时通知用户的最佳方式

Question

i have a calendar app, i create appointments and i performe an auto delete for them after 5 minutes, i am trying to get all appointments that are 1 minute away from expiring and send a notification to my front-end saying that these appointments are close to be expired.

i made an example but i don't get any results:

async function sendNotification(req: Request, res: Response) {
  const DATE = new Date();
  const NEXT_MINUTE = new Date(DATE.setMinutes(DATE.getMinutes() + 1));
  

  const appointments = await Calendar.aggregate([
    { $match: { expireAt: { $lt: NEXT_MINUTE } } },
  ]);
  console.log("LAST_MINUTE >>", NEXT_MINUTE);

  res.status(200).json(appointments);
}

my question is how to get appointments that will expire in 1 minute?

Answer 1

This is probably due to this note about aggregations in Mongoose...

unlike query filters, Mongoose also doesn't cast aggregation pipelines. That means you're responsible for ensuring the values you pass in to an aggregation pipeline have the correct type.

There's probably an issue with passing in a Date instance.

You don't appear to actually need an aggregate. Try using a normal query instead

const NEXT_MINUTE = new Date(Date.now() + 60000);

const appointments = await Calendar.find({
  expireAt: { $lt: NEXT_MINUTE }
});