Node mongoose embedded document array - mongodb

Question

I have my sample userSchema here:
{
"_id": objectId("6092076ba811e50b565497ec"),
"username": "test#gmail.com",
"address_book": [{
"_id": objectId("6092b1120f7e370b954a2708"),
"address": "address1",
"address2": "address2",
}, {
"_id": objectId("6093edcb88796b0a5eba19a3"),
"address": "test1",
"address2": "test2",
}]
}
Can I find user by
objectId("6092076ba811e50b565497ec") and address_book._id object("6093edcb88796b0a5eba19a3")
and it return only the address_book that I selected? my expected return data should look like this
{
"_id": objectId("6092076ba811e50b565497ec"),
"username": "test#gmail.com",
"address_book": {
"_id": objectId("6093edcb88796b0a5eba19a3"),
"address": "test1",
"address2": "test2",
}
}
here is my sample function
let user = [];
await User.findOne({
_id: id,
"address_book._id": address_id,
})
.then((result) => {
console.log(result);
user = result;
})
.catch((err) => console.log(err));
return user;
with this I get all address_book
and also can is there and updateOrCreate function by address_book._id?
Thank you in advance.

Answer 1

You can use aggregation operators in find method starting from MongoDB 4.4,
$filter to iterate loop of address_book array and match _id condition
$first to select first element from above filtered result
await User.findOne({
_id: id,
"address_book._id": address_id
},
{
username: 1,
address_book: {
$first: {
$filter: {
input: "$address_book",
cond: { $eq: ["$$this._id", mongoose.Types.ObjectId(address_id)] }
}
}
}
})
Playground

Answer 2

elemMatch is what you are looking for according to me. elemMatch for projection not just the match.
db.<collection name>.find({
< search using elem match >
}, {
games: {
$elemMatch: {
//put your projection piece here, whatever selective what you want, check the example on documentation
score: {
$gt: 5
}
}
},
//anything else that you would want apart from within array projection
})
Update :
Data
[
{
"_id": "6092076ba811e50b565497ec",
"username": "test#gmail.com",
"address_book": [
{
"_id": "6092b1120f7e370b954a2708",
"address": "address1",
"address2": "address2",
},
{
"_id": "6093edcb88796b0a5eba19a3",
"address": "test1",
"address2": "test2",
}
]
}
]
Command
db.collection.find({},
{
address_book: {
$elemMatch: {
address: "test1"
}
}
})
Result
[
{
"_id": "6092076ba811e50b565497ec",
"address_book": [
{
"_id": "6093edcb88796b0a5eba19a3",
"address": "test1",
"address2": "test2"
}
]
}
]
Playground