how should i make my database fetch continously - database

Question

function shield() {
setInterval(async function () {
const ProfileModelS = require("../models/ProfileSchema");
await ProfileModelS.find({}).then((doc) => {
doc.forEach(async (u) => {
if (u.ShieldPoints <= 0) return console.log(u.Name);
if (u.ShieldPoints > 0) {
await ProfileModelS.findOneAndUpdate(
{ userID: u.userID },
{
$inc: {
ShieldPoints: -1,
},
},
console.log("done")
);
}
});
});
}, 1000);
}
module.exports = shield
I want my mongodb to fetch the model on every Interval but its not doing that, whenever i run my code it fetches the model for example, it will fetch
[{name: 'Joseph' , Points: 10}, {name: 'carman' , Points: -1}, {name: 'thee' , Points: 2}]
according to code it will properly not reduce the points of objects whose points are less than 0,
but it will go on decreasing points of object more than 0, i want it to stop reducing points if the objects point reaches 0, and it should go on decreasing the points of object whose points are greater than 0
In short the process for a particular object should be stop once it points reaches 0

Answer 1

You could try using Promise.all to iterate over all of the retrieved models, as you seem to want to perform an async operation on every instance with ShieldPoints > 0 and your findOneAndUpdate operations are independent of one another.
function shield() {
// Import the model schema
const ProfileModelS = require("../models/ProfileSchema");
setInterval(async function () {
// Retrieve all models
const users = await ProfileModelS.find();
// Parallelise the process of updating the models that need to be updated
Promise.all(
users.map(async (user) => {
if (user.ShieldPoints > 0) {
await ProfileModelS.findOneAndUpdate(
{ userID: user.userID },
{
$inc: {
ShieldPoints: -1,
},
},
);
};
})
);
}, 1000);
}
module.exports = shield
However, if your findOneAndUpdate operations do not complete within the 1000ms interval, then the code will issue a second findOneAndUpdate operation for those same model instances. This could then cause your models to update more than once, which is unintended behaviour. To address this, you would need to add some form of guard against this.