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Mongo / Mongoose - Push object into document property array on condition

I have a document stored on mongo that, amongst others, contains a property type of an array with a bunch of objects inside. I am trying to push an object to that array. However each object that gets pushed to into the array contains a date object. How I need it to work is if an object with that date already exists then dont push the new object into the array.
I'm been playing with it for a while, trying to run update and elemMatch queries etc, but I can't figure it out. I have a long draw out version below, as you can see I'm making 2 separate requests to the database, can someone help me reduce this to something simpler?
UserModel.findById(req.user._id, (err, doc) => {
if (err) {
return res.sendStatus(401);
}
const dateExists = doc.entries.find((entry) => entry.date === date);
if (dateExists) {
res.sendStatus(401);
} else {
UserModel.findByIdAndUpdate(
req.user._id,
{
$push: {
entries: {
date,
memo,
},
},
},
{ safe: true, upsert: true, new: true },
(err, doc) => (err ? res.sendStatus(401) : res.sendStatus(200))
);
}
});
Thanks.

db.users.updateOne({
_id: req.user._id,
"entries.date": date,
},
{
$push: {
entries: {date,memo},
}
})
https://docs.mongodb.com/manual/reference/method/db.collection.updateOne/index.html

Best way to update value of an object inside mongodb object

This is how I store each element in my mongodb collection.
{
_id: 'iTIBHxAb8',
title: 'happy birthday',
votesObject: { happy: 0, birthday: 0 }
}
I made a very dirty work around which I am not at all proud of which is this...
//queryObject= {id,chosenvalue};
let queryObject = req.query;
let id = Object.keys(queryObject)[0];
let chosenValue = queryObject[id];
db.collection("voting")
.find({ _id: id })
.toArray((err, data) => {
let { votesObject } = data[0];
votesObject[chosenValue] += 1;
data[0].votesObject = votesObject;
db.collection("voting").replaceOne({ _id: id }, data[0]);
res.redirect("/polls?id=" + id);
});
So basically what this does is It gets the chosen value which may be "happy" or the "birthday" from the above example.
Finding the complete object from the collection which matches the id.
Incrementing the chosen value from the found object.
Using replaceOne() to replace the previous object with the newly changed object.
I am incrementing the value inside chosen value by one everytime this piece of code executes.
This works perfectly fine but I want to know if there is any way to directly update the chosen value without all this mess. I could not find a way to do it else where.

you can use mongoose findOneAndUpdate
It will be something like
const updateKey = "votesObject.$."+ chosenValue
let incQuery = {}
incQuery[updateKey] = 1
Model.findOneAndUpdate(
{ _id: id },
{ $inc: incQuery },
{ new : false },
callback
)

You can use $inc operator.
Try something like this:
db.collection.update({
"_id": id
},
{
"$inc": {
"votesObject.birthday": 1
}
})
This query will increment your field birthday in one.
Check mongo playground exaxmple here

How can I add to this schema array with mongoose?

Here's the user schema and the part I want to update is ToDo under User.js (further down). I am attempting to add new data to an array within the db.
data.js
app.post("/data", loggedIn, async (req, res) => {
console.log(req.body.content);
let content = { content: req.body.content };
User.update({ _id: req.user._id }, { $set: req.body }, function (err, user) {
if (err) console.log(err);
if (!content) {
req.flash("error", "One or more fields are empty");
return res.redirect("/");
}
user.ToDo.push(content);
res.redirect("/main");
});
});
User.js
new mongoose.Schema({
email: String,
passwordHash: String,
ToDo: {
type: [],
},
date: {
type: Date,
default: Date.now,
},
})
Originally I was trying the .push() attribute, but I get the error:
user.ToDo.push(content);
^
TypeError: Cannot read property 'push' of undefined

First of all, your problem is the callback is not the user. When you use update the callback is something like this:
{ n: 1, nModified: 1, ok: 1 }
This is why the error is thrown.
Also I recommend specify the array value, something like this:
ToDo: {
type: [String],
}
The second recommendation is to do all you can into mongo query. If you can use a query to push the object, do this instead of store the object into memory, push using JS function and save again the object into DB.
Of course you can do that, but I think is worse.
Now, knowing this, if you only want to add a value into an array, try this query:
var update = await model.updateOne({
"email": "email"
},
{
"$push": {
"ToDo": "new value"
}
})
Check the example here
You are using $set to your object, so you are creating a new object with new values.
Check here how $set works.
If fields no exists, will be added, otherwise are updated. If you only want to add an element into an array from a specified field, you should $push into the field.
Following your code, maybe you wanted to do something similar to this:
model.findOne({ "email": "email" }, async function (err, user) {
//Here, user is the object user
user.ToDo.push("value")
user.save()
})
As I said before, that works, but is better do in a query.

Mongoose findOneAndUpdate on array of subdocuments

I'm trying to replace an array of sub-documents with a new copy of the array.
Something like...
var products = productUrlsData; //new array of documents
var srid = the_correct_id;
StoreRequest.findOneAndUpdate({_id: srid}, {$set: {products: products}}, {returnNewDocument : true}).then(function(sr) {
return res.json({ sr: sr}); //is not modified
}).catch(function(err) {
return res.json({err: err});
})
The products var has the correct modifications, but the returned object, as well as the document in the db, are not being modified. Is this not the correct way to replace a field which is an array of subdocuments? If not, what is?

I am a bit late to the party plus I am really in a hurry -- but should be:
StoreRequest.updateOne(
{ _id: srid },
{ $set: { 'products.$': products }},
{ new: true });
I couldn't make it work with findOneAndUpdate but the above does work.

Update query that handles duplicates and increment operator

Background:
I have an update query on collection called alerts that runs each
time a "flow" is received.
I have an array of objects in my alert's document called
blacklistedCommunication.
What should happen:
When a new flow arrives, then the alerts doc is updated only if the flow's client_addr and server_addr are not already present in blacklistedCommuication. While at the same time, if we do find duplicates, it should only increment the flowCount.
The current query:
The below update query works to push new objects to blacklistedCommunication object if it's not present already.
However, if it is indeed present, it will not update the flowCount
How can I incorporate this logic into the query? Do I need to write a separate update query in case of duplicates?
alerts.update({
alertLevel: "orgLevelAlert",
alertCategory: "blacklistedServersViolationAlert",
alertState: "open",
'blacklistedCommunication.client': {
$ne: flow.netflow.client_addr
},
// 'blacklistedCommunication.server': {
// $ne: flow.netflow.server_addr
// }
}, {
$set: {
"misc.updatedTime": new Date()
},
$inc: {
flowCount: 1
},
$push: {
blacklistedCommunication: {
client: flow.netflow.client_addr,
server: flow.netflow.server_addr
}
}
});

You can use $addToSet instead of $push. It will ensure unique {client:*,server:*} object within blacklistedCommunication and will always update flowCount:
alerts.update({
alertLevel: "orgLevelAlert",
alertCategory: "blacklistedServersViolationAlert",
alertState: "open"
}, {
$set: {
"misc.updatedTime": new Date()
},
$inc: {
flowCount: 1
},
$addToSet: {
blacklistedCommunication: {
client: flow.netflow.client_addr,
server: flow.netflow.server_addr
}
}
});