Find subdocument object in another db - arrays

Question

I'm trying to check each email of attendees and see if they are a registered user. If not, I will send them an email (not yet coded, will do later).
Here's the event and user schema:
const UserSchema = new Schema({
name: {
type: String,
required: true
},
email: {
type: String,
required: true
},
password: {
type: String,
required: true
},
date: {
type: Date,
default: Date.now
}
});
const Event = new Schema({
title: {
type: String,
required: true
},
user: {
type: mongoose.Schema.Types.ObjectId,
ref: 'users'
},
attendees:[
{email: {
type: String,
required: true
},
name: {
type: String,
required: true
},
status: {
type: String
}}
]
});
router.post('/', auth, async (req, res) => {
const {title,
attendees
} = req.body
if (!title) {
return res.status(400).json({ msg: 'Please enter a title' });
}
try{
const newEvent = new Event({
title,
user: req.user.id,
attendees: attendees.map(x => ({
email: x.email,
name: x.name,
status: x.status,
})),
});
const attendeeExists = await User.findOne({"attendees.email":email});
if (!attendeeExists) throw Error("User doesn't exist. Send email");
The last two lines are giving me an error: email is not defined.
Not sure what I'm missing.
This works in the user routes:
const user = await User.findOne({ email });

Answer 1

Thanks #ambianBeing, your solution helped me get a working model.
const email = attendees.map((a) => a.email);
const attendeesFound = await User.find({email});

Answer 2

For checking any of the attendee's email found, .find() with $in can be used which'll return the users found with any of the email ids.
/*collect all emails to test*/
const emails = attendees.map((a) => a.email);
const attendeesFound = await User.find({ "email": { $in: emails } });
Another Mongoose syntax wihich does the same thing as above:
/*collect all emails to test*/
const emails = attendees.map((a) => a.email);
const attendeesFound = await User.find({}).where("email").in(emails);