Node : Mongoose Updating User Schema with arrays - node.js

Question

Here is my User Schema
{
"user_collection":[
{
"_id":"xxx",
"name":"NAME",
"prescription":
{
"doctor_id":
[{
"_id":"xxx",
"medicine_id":"MEDICINE_ID",
}]
},
"meal":{
"meal_name":{
"start_time":"START_TIME",
"end_time":"END_TIME"
}
},
"created_at":"CREATED_AT",
"updted_at":"UPDATED_AT"
}
]
}
Note : _id given just for understanding
I need to insert document inside the prescription array. Here is the condition
If the new doctor_id is given, it should add in the prescription array like
{
"_id" : ObjectId("5813288eaa0f1231de477d92"),
"name" : "andrew",
"prescription" : [
{
"prescription" : [
{
"_id" : ObjectId("58143d484e26a229873b0528"),
"medicine_id" : "10011241343"
}
],
"_id" : ObjectId("58143d484e26a229873b0527"),
"doctor_id" : "5813221ace684e2b3f5f0a6d"
}
]
}
And if i given the doctor_id that already exists it should add like
{
"_id" : ObjectId("5813288eaa0f1231de477d92"),
"name" : "andrew",
"prescription" : [
{
"prescription" : [
{
"_id" : ObjectId("58143d484e26a229873b0528"),
"medicine_id" : "10011241343"
}
],
"prescription" : [
{
"_id" : ObjectId("58143d484e26a229873b0529"),
"medicine_id" : "10011241349"
}
],
"_id" : ObjectId("58143d484e26a229873b0527"),
"doctor_id" : "5813221ace684e2b3f5f0a6d"
}
]
}
What i have tried is
dbModel.user.update({
_id: req.body.user_id
}, {
$set: {
prescription: [ { "doctor_id" : req.body.doctor_id, "prescription" : [
{
"medicine_id" : req.body.medicine_id
}]} ],
}
}, {
upsert: true
}, function(err) {
if (err) {
res.status(202).json({
"success": "0",
"message": err
})
} else {
res.status(200).json({
"success": "1",
"message": "Prescription given successfully"
});
}
})
I don't know how to check whether the doctor_id already exists and if it does not exists it should add a new array, and if it exists it should add inside the existing arrays

Answer 1

Take a look in this answer.
But basically you can use the $ operator which identifies an element in an array.
You can see here some mongodb array operators.