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Updating a Subdocument in MongoDB

I am trying to create a database for my Giveaway Bot. It consist of 2 collections, Main (holding settings) and Giveaway which is nested in under the Main collection. I can create my giveaway's without problems. However I want to add some data later on using findOneAndUpdate.
Running the code below I always get this error: Updating the path 'giveaways.duration' would create a conflict at 'giveaways'. Can anyone help solving this issue ?
schema.js
const giveawaySchema = new mongoose.Schema({
_id: String,
destination: String,
duration: String,
winners: String,
price: String,
})
const mainSchema = new mongoose.Schema({
_id: String,
log_channel_id: String,
admin_roles: [],
giveaways: [giveawaySchema],
const Main = mongoose.model("mainSchema", mainSchema);
const Giveaway = mongoose.model("giveawaySchema", giveawaySchema);
module.exports = { Main, Giveaway }
});
Part of my code used for updating:
const mongoose = require("mongoose")
const {Main, Giveaway} = require("../models/schema.js")
const newestGiveaway = await Main.findOneAndUpdate(
{
_id: guildId,
'giveaways._id': giveaway_id,
},
{
"$set":{
"giveaways.duration": "3d",
"giveaways.winners": "20",
"giveaways.price": "Price to Win",
},
},
{
upsert: true,
}
Thank you for your help :)
A small side question. I have fetched the Main document (the parent) before already can I make my search cheaper/ more efficent by only searching through this instead of running the findOneandUpdate method on the whole database ?
Edit 1:
I found that it is neccesary to use the $ operator and have updated my code. However I still get the same error:
{
$set:{
"giveaways.$.duration": "3d",
"giveaways.$.winners": "20,
"giveaways.$.price": "Price to Win",
},
},
Edit 2:
Just to clarify, the creation and nesting of the giveawaySchemas works but I am not able to update the nested document by using the code above.
My child component is already created by using the code below. I now want to update this child (newGiveaway with _id of 1)
const currentGuild = await Main.findOne({_id: guildId})
const newGiveaway = await Giveaway.create({
_id: 1,
destination: 12345678,
});
currentGuild.giveaways.push(newGiveaway)

You can change your schema declaration to use a ref to the giveawaySchema:
const giveawaySchema = new mongoose.Schema({
_id: String,
destination: String,
duration: String,
winners: String,
price: String,
})
const mainSchema = new mongoose.Schema({
_id: String,
log_channel_id: String,
admin_roles: [],
giveaways: [{
type: mongoose.Schema.Types.ObjectId,
ref: 'giveawaySchema'
}],
const Main = mongoose.model("mainSchema", mainSchema);
const Giveaway = mongoose.model("giveawaySchema", giveawaySchema);
module.exports = { Main, Giveaway }
Then, you will just need to update your giveaways directy:
const mongoose = require('mongoose');
const { Giveaway } = require('../models/schema.js');
const newestGiveaway = await Main.findByIdAndUpdate(
giveaway_id,
{
duration: '3d',
winners: '20',
price: 'Price to Win',
},
{
new: true,
}
);

In the mainSchema you define giveaways field as an array of giveawaySchema object. So, you have to treat it as an array, not an object. If you want to treat it as an object, you will have to update mainSchema by removing square bracket at giveawaysSchema.
Relevant Question for how to pushing item into mongo array

Finding a document in a collection whose field is an objectId but refers to another collection

I have these two collections defined as follows
let BookSchema = new mongoose.Schema({
title: String,
author: {
type: mongoose.Object.Types.ObjectId,
ref: "author"
}
})
let BookModel = mongoose.model("Books", BookSchema)
and another schema
let AuthorSchema = new mongoose.Schema({
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let AuthorModel = mongoose.model("author", AuthorSchema)
I want to search the BookModel using a query to find any Book where the title of the book or the name of the author (NOTE: not author ID but name ) includes the query.
I have defined the following code
let query = "";
BooksModel.find({title: {$regex: query, $options:'i'}})
This searches for the title, how do i also make it search that the name of the artist whose id is in the BooksModel includes the query ?

You can't do that in a single query using MongoDB, you'll need to have two separate queries.
const queryRegexFilter = {
$regex: query,
$options: 'i'
};
const authors = await AuthorModel.find({
name: queryRegexFilter
}).select('_id');
const authorsIds = authors.map(author => author._id);
const books = await BookModel.find({
$or: [
{ title: queryRegexFilter },
{ authorId: { $in: authorsIds } }
]
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doStuffWithBooks(books);

How to write a mongoDB query to match any element in an array of subdocuments against any element in a Typescipt Array?

I have a mongoDB database containing Events. Each event is defined by a number of fields, including an array of genres (which are subdocuments consisting of a {genre and subGenre}).
For example: an event could be of {genre: "music", subGenre: "jazz"}, and {genre: "music", subGenre: "blues"}. See event.js - the model. In this case, 2 "genre" sub documents are added to the "genres" array in the Event document in the database.
Back in my node application - see query.ts - I am trying to work out how to run a query that lets the user search for all events that match their genre preferences.
So:
the Event is defined by an array of genres (in the database), and
the user's preferences are defined by an array of genres (in the
application).
I am looking to define a mongoDB query that returns all Events where there is a match of any 1 {genre, subGenre} combination between the 2 arrays.
I looked into $in Query Selector in the mongoDB documentation and suspect it might need to be used... but programmatically, how do I write a query that expands to include all the values in the variable "searchGenres" in query.ts?
Thanks a lot in advance for your thoughts.
event.js: mongoDB Model for 'Events" defined using Mongoose - snippet:
let mongoose = require('mongoose');
let EventSchema = new mongoose.Schema({
genres: [
{
genre: String,
subGenre: String
}
]
)};
module.exports = mongoose.model('Event', EventSchema);
query.ts:
import mongoose = require('mongoose');
let Event = require ('../models/event');
class Genre {
genre: string;
subGenre: string;
constructor (gen: string, sub: string) {
this.genre = gen;
this.subGenre = sub;
}
}
async function runQuery()
{
let searchGenres : Array<Genre> = new Array<Genre>();
// populate searchGenres with some data here... e.g.
const searchGenre1 : Genre = new Genre ('music', 'jazz');
const searchGenre2 : Genre = new Genre ('music', 'rock');
searchGenres.push(searchGenre1);
searchGenres.push(searchGenre2);
// Query logic here:
// Return all events from the database, if the 'genres' array
// in the document matches any element in the searchGenres array
// defined above..
const events = await Event.find ({
'genres': {?help? }
});
}
```

After some self-education today, I have come up with a solution, which I am happy with - to append to end of query.ts:
type GenreQuerySelector = { genres: { $elemMatch: { 'genre': string; 'subGenre': string; }; }; };
let querySelectors : Array< GenreQuerySelector > = new Array< GenreQuerySelector >();
for (let genre of searchGenres) {
const genreQuery : GenreQuerySelector = {
genres: {
$elemMatch: {
'genre': genre.genre,
'subGenre': genre.subGenre
}
}
};
querySelectors.push(genreQuery);
};
const events = await Event.find ({ $or: querySelectors }).exec();

how do I query from parent model a array of other model in Mongoose?

I have two Schema for user & todo. Every todo has an owner as a user, every user has an array of todos.
// user.js
const TodoSchema = require('./todo').TodoSchema;
var UserSchema = mongoose.Schema({
name: {
type: String,
required: true
},
todos: {
type: [TodoSchema]
}
});
module.exports.UserSchema = UserSchema;
module.exports.UserModel = mongoose.model('UserModel', UserSchema);
// todo.js
var TodoSchema = mongoose.Schema({
body: {
type: String, required: true
},
owner: {
type: mongoose.Schema.Types.ObjectId,
ref: 'UserModel',
required: true
}
});
module.exports.TodoSchema = TodoSchema;
module.exports.TodoModel = mongoose.model('TodoModel', TodoSchema);
I entered data like this.
var nUser = new UserModel({
name: "Alex
)};
nUser.save().then(user => {
var t = new TodoModel({
body: "my new todo",
owner: user._id
});
t.save().then();
});
But the problem is I want to get all the todos from a specific user, something like this...What is the correct way?
UserModel.findOne({name: "Alex"})
.then(user => {
// user.todos
});
P.S.
I can do this like TodoModel.find({owner: specific_user._id}), but I want it from UserModel.

Since you're asking for the proper way of doing it, I am gonna start with your User Schema. If you want to find all the todos of a user, then putting the todo documents inside an array in the User document is not required. So you should probably remove that from your schema.
After that you can use a simple aggregation to get your desired outcome.
UserModel.aggregate([
{
$match:{
name:"Alex"
}
},
{
$lookup:{
from:"todomodels",
localField:"$_id",
foreignField:"$owner",
as:"todos"
}
}
])
this will return all the todos for that user in an array of the same name.

How can I double-query two mongoose values?

I'm building a buildQuery to get posts for a social feed.
When users make a post, their university is saved in the post as university. They can also choose to make sure that ONLY other students from their same university can see it.
If they want to do so, then uniOnly is set to true on the post model.
Here's part of the PostSchema:
const PostSchema = new Schema({
university: {
type: String,
required: true
},
uniOnly: {
type: Boolean,
required: true
}
});
In the buildQuery below, the university, uni of the user, (stored in their profile document) requesting the feed is passed in as an parameter.
So what I'm trying to do is check that IF uniOnly is set to true on the post and the uni coming in is NOT the same as university on the post, then it should NOT be seen in the feed.
How can I do this? Should I be using $where? Or an if statement some
how?:
const buildQuery = (criteria) => {
const { uni } = criteria;
const query = {};
// Should I be using $where?
query.uniOnly = { $where: }
return query;
};
The buildQuery is quite large so I've cut it down to what is relevant.
Thank you

If you want to query for posts where uniOnly = false OR university = criteria.uni, then you can use $or to combine the terms logically:
const buildQuery = (criteria) => {
const query = { $or: [ {uniOnly: false}, {university: criteria.uni} ] };
return query;
};