Mongoose update only fields available in request body - mongodb

Question

I am trying to update one document using findOneAndUpdate and $set but I clearly missing something very crucial here because the new request is overwriting old values.
My Device schema looks like this:
{
deviceId: {
type: String,
immutable: true,
required: true,
},
version: {
type: String,
required: true,
},
deviceStatus: {
sensors: [
{
sensorId: {
type: String,
enum: ['value1', 'value2', 'value3'],
},
status: { type: Number, min: -1, max: 2 },
},
],
},
}
And I am trying to update the document using this piece of code:
const deviceId = req.params.deviceId;
Device.findOneAndUpdate(
{ deviceId },
{ $set: req.body },
{},
(err, docs) => {
if (err) {
res.send(err);
} else {
res.send({ success: true });
}
}
);
And when I try to send a request from the postman with the body that contains one or multiple sensors, only the last request is saved in the database.
{
"deviceStatus": {
"sensors": [
{
"sensorId": "test",
"status": 1
}
]
}
}
I would like to be able to update values that are already in the database based on req.body or add new ones if needed. Any help will be appreciated.

Answer 1

The documentation said:
The $set operator replaces the value of a field with the specified
value.
You need the $push operator, it appends a specified value to an array.
Having this documents:
[
{
_id: 1,
"array": [
2,
4,
6
]
},
{
_id: 2,
"array": [
1,
3,
5
]
}
]
Using $set operator:
db.collection.update({
_id: 1
},
{
$set: {
array: 10
}
})
Result:
{
"_id": 1,
"array": 10
}
Using $push operator:
db.collection.update({
_id: 1
},
{
$push: {
array: 10
}
})
Result:
{
"_id": 1,
"array": [
2,
4,
6,
10
]
}

Answer 2

you want to using $push and $set in one findOneAndUpdate, that's impossible, I prefer use findById() and process and save() ,so just try
let result = await Device.findById(deviceId )
//implementation business logic on result
await result.save()

Answer 3

If you want to push new sensors every time you make request then update your code as shown below:
const deviceId = req.params.deviceId;
Device.findOneAndUpdate(
{ deviceId },
{
$push: {
"deviceStatus.sensors": { $each: req.body.sensors }
}
},
{},
(err, docs) => {
if (err) {
res.send(err);
} else {
res.send({ success: true });
}
}
);
Update to the old answer:
If you want to update sensors every time you make request then update your code as shown below:
const deviceId = req.params.deviceId;
Device.findOneAndUpdate(
{ "deviceId": deviceId },
{ "deviceStatus": req.body.sensors },
{ upsert: true },
(err, docs) => {
if (err) {
res.send(err);
} else {
res.send({ success: true });
}
}
);