Find nested array elements - node.js

Question

This is my schema:
Appliance = new Schema({
appliance_name: {type:String},
appliance_id: {type:String},
appliance_description: {type:String},
keywords: [{ type: String}],
appliance_type: { type: String},
appliance_status: { light: { write_state: Number, read_state: Number },
fan: {write_state: Number, read_state: Number, write_speed: Number, read_speed: Number}
}
});
Room= new Schema({
name: {type: String, required:true},
device_auth_code: {type: String},
alt_name: {type:String},
keywords: [{type: String}],
appliance: [Appliance]
});
Home = new Schema({
name: { type: String, required: true},
description: {type: String},
administrator: {type : mongoose.Schema.Types.ObjectId, ref: 'User', required: true},
users: [{
_id: {type : mongoose.Schema.Types.ObjectId, ref: 'User'},
email: {type: String},
name: { type: String},
status: { type: Number}
}],
rooms: [Room]
});
And here is the typical home.
"type": true,
"code": "GET_SUCCESS",
"homes": {
"_id": "58760ff6045e332b81449b42",
"description": "",
"administrator": "586df1e06485de5fc48b72a5",
"name": "CM",
"__v": 9,
"rooms": [
{
"name": "RK",
"alt_name": "RKa",
"_id": "58775437234451346ce3d967",
"appliance": [
{
"_id": "5877546f234451346ce3d968",
"appliance_type": "Light",
"appliance_name": "TubeLights",
"keywords": []
}
],
"keywords": []
}
],
"users": []
}
}
Home has nested array of rooms and each room has nested array of appliances.
Home.findOne({'room.appliance._id': appliance_id}) would return the whole document. The $ operator wouldn't work I would have to imagine.
Is it possible to receive that particular appliance or the whole document with that particular room and appliance only being returned?
How do I find a particular appliance and return that appliance?

Answer 1

Here you've used mongoose subdocs architecture in your home schema definition. So you could retrieve any particular room:
Home.findById(home_id, function(err, home){
var room = home.rooms.id(room_id);
res.json(room)
});
or a particular appliance:
Home.findById(home_id, function(err, home){
var room = home.rooms.id(room_id);
var appliance = room.appliance.id(appliance_id);
res.json(appliance)
});