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How can I delete an array entry in MongoDB with a delete API?

I am building an application that manages time sensitive tasks. I have APIs to create tasks and retrieve tasks, and I'm currently trying to get my delete API to work.
An employee has an array in MongoDB that contains todo tasks with text and I'm trying to delete the task by ID in SoapUI. With my current code, the delete request just sort of times out after a minute or so.
Here's my current delete API
router.delete("/:empId/tasks/:id", async (req, res) => {
try {
Employee.findByIdAndDelete(
{
empId: req.params.empId,
},
{
$pull: {
todo: {
_id: req.params.id,
},
},
}
);
} catch (e) {
console.log(e);
res.status(500).send({
message: "Internal server error: " + e.message,
});
}
});
Current schema
let itemSchema = new Schema({
text: { type: String },
_id: { type: String },
});
task.service
deleteTask(empId: number, task: string, _id: number): Observable<any> {
return this.http.delete('/api/employees/' + empId + '/tasks/' + _id);
}
and an example of an employee document in MongoDB
{"_id":{"$oid":"61797a51d15ad09b88d167af"},"empId":"1012", "firstName":"web","lastName":"developer","__v":1,"done":[],"todo":[{"_id":"1","text":"test"}]}

When you use findByIDAndDelete, it deletes that entire document. What you need is to update that particular document using update()/findOneAndUpdate()/findByIdAndUpdate(). Also you should either await/use a callback to return the value, like,
collection.findOneAndUpdate({_id:docId },{
$pull: {"todo":{"_id":yourId} },
},
function(error, data){
if(error){ return error}
else {return data}
})

NodeJS : Mongoose findByIdAndUpdate() returns null

Consider the following code on NodeJS for updating a Document By id:
router.put('/:orderId', async(req, res) => {
let update_orderId = req.params.orderId;
let new_item = req.body.item;
let new_item_desc = req.body.item_desc;
let new_quantity = req.body.quantity;
let new_unit_price = req.body.unit_price;
let new_total_cost = new_quantity * new_unit_price;
let new_status = req.body.status;
let new_priority = req.body.priority;
await RequestPermissionOrderSchema.findByIdAndUpdate( update_orderId, {
$set: {
item: new_item,
item_desc: new_item_desc,
quantity: new_quantity,
unit_price: new_unit_price,
total_cost: new_total_cost,
status: new_status,
priority: new_priority,
directOrder: false
}
},
{ new: true, useFindAndModify: false}, function (err, docs) {
if (err) {
console.log(err);
res.send(err);
} else {
console.log("Updated Request Permission Order : ", docs);
res.json(docs);
}
});
});
Everything is according to the latest documentation of Mongoose 5.10.9 and the schema also contains all the properties specified under $set: { ... } . But when I execute, I get the output as follows in the console:
updated Request Permission Order : null
I also make sure of whether the _id is available in the mongoDB database and that object ID is there. I can't seem to find what I did wrong. Really appreciate any help on this !
Also, note that I want to update by the _id auto-generated by MongoDB with each document.

Just pass the JSON object, remove the $set
await RequestPermissionOrderSchema.findByIdAndUpdate( update_orderId, {
$set: { // REMOVE THIS $set
item: new_item,
item_desc: new_item_desc,
quantity: new_quantity,
unit_price: new_unit_price,
total_cost: new_total_cost,
status: new_status,
priority: new_priority,
directOrder: false
} // REMOVE THIS ALSO
},
Only the JSON object.

Mongoose populate method only storing one Object

I'm trying to access the array of Message Models that is stored in my Conversation Model. However, when I use the populate method to try to store the Message models as an array, only the first Message is showing up.
socket.on('connected', function (data) {
//load all messages
const filter = { roomId: data.roomid };
(async () => {
console.log('searching for Schema');
let conversation = await Conversation.findOne(filter)
.populate('messages')
.exec(function (err, message) {
if (err) console.log('no schema found');
var array = message.messages;
console.log(array);
// printing only first Message
});
})();
});
Conversation Schema
const ConversationSchema = new mongoose.Schema(
{
roomId: {
type: String,
required: true
},
messages: {
type: mongoose.Schema.Types.ObjectId, ref: 'Message'
}
},
{
timestamps: true
}
);

populate method not store message as an array.Population is the process of automatically replacing the specified paths in the document with document(s) from other collection(s).Refer this for more detail
To solve your problem modify declaration of messages field in Conversation Schema
messages: [{
type: mongoose.Schema.Types.ObjectId, ref: 'Message'
}]

Node JS preventin users from deleting other user's products

I have a REST API built with Node JS and I'm currently using MongoDB as my database. I want to prevent the users from deleting another user's products and for this I checked if the userId from the decoded token is the same as the product userId.
Product schema
const mongoose = require("mongoose");
const productSchema = mongoose.Schema(
{
_id: mongoose.Schema.Types.ObjectId,
userId: mongoose.Schema.Types.ObjectId,
name: { type: String, required: true },
price: { type: Number, required: true },
productImage: { type: String, required: false },
category: {
type: mongoose.Schema.Types.ObjectId,
ref: "Category",
required: true
},
gender: { type: String, required: true }
},
{ timestamps: { createdAt: "created_at" } }
);
module.exports = mongoose.model("Product", productSchema);
The delete product method:
const id = req.params.productId;
Product.findById({ _id: id }).then((product) => {
if (product.userId != req.user._id) {
return res.status(401).json("Not authorized");
} else {
Product.deleteOne({ _id: id })
.exec()
.then(() => {
return res.status(200).json({
message: "Product deleted succesfully",
});
})
.catch((err) => {
console.log(err);
return res.status(500).json({
error: err,
});
});
}
});
};
As you guys see first I'm searching executing the findByID method to access the userId property of the product, then I'm comparing the userId from the response with the userId from the decoded token.
I don't think my method is very efficient since it's running both findById and deleteOne methods.
Can you help me with finding a better solution for this?

as Guy Incognito mentioned, what you are trying to do is an OK thing and you may want to keep it this way in case you want to send a 404 status stating the product they are trying to remove does not exist.
however, if you are trying to do it with only one request
Product.deleteOne({ _id: id, userId: req.user._id })
hope it helps!

Populate subdocument in parent document Array Mongoose

I'm very new to JavaScript and Mongoose. I'm building a small project using express, mongoose and node.js.
I have a mongoose model - Client that has an Array of Transactions
var Client = mongoose.model('Client', {
name: {
type: String,
required: true,
minlength: 1
},
email: {
type: String
},
phone: {
type: Number
},
createdAt: {
type: Number,
default: null
},
transactions: [{ type: mongoose.Schema.Types.ObjectId, ref: 'Transaction' }],
_creator: {
type: mongoose.Schema.Types.ObjectId,
required: true
}
});
module.exports = {Client};
This is Transaction model:
var Client = require('./client');
var Transaction = mongoose.model('Transaction',{
_creator : { type: mongoose.Schema.Types.ObjectId, ref: 'Client' },
amount : {type: Number, min: 0},
date : {type: Number,default: null},
total: {type: Number,default: null}
});
module.exports = {Transaction};
When I POST a new Transaction it goes through and saves in db:
app.post('/clients/:id/transactions', authenticate, (req, res) => {
var id = req.params.id;
var transaction = new Transaction({
amount: req.body.amount,
date: new Date().getTime(),
total: req.body.total,
_creator: req.params.id
})
if (!ObjectID.isValid(id)) {
return res.status(404).send();
}
transaction.save().then((doc) => {
Client.findOneAndUpdate({
_id: id,
_creator: req.user._id,
transactions: req.body.transaction
});
res.send(doc);
}, (e) => {
res.status(400).send(e);
});
});
I am also able to GET all the transactions associated with the client:
app.get('/clients/:id/transactions', authenticate, (req, res) => {
var id = req.params.id;
if (!ObjectID.isValid(id)) {
return res.status(404).send();
}
Transaction.find({
_creator: id
}).then((transactions) => {
res.send({transactions});
}).catch((e) => {
res.status(400).send();
});
});
But when I make a GET call to '/clients' - Array of Transactions is empty:
{
"clients": [
{
"_id": "1095d6de3867001108b803",
"name": "Peter",
"email": "peter#gmail.com",
"phone": 1232321,
"_creator": "5321df6d57868ec7001108b801",
"__v": 0,
"transactions": [],
"createdAt": null
} ]
}
And this is the GET call to /clients
app.get('/clients', authenticate, (req, res) => {
Client.find({
_creator: req.user._id,
})
.populate('transactions.transaction')
.then((clients) => {
res.send({clients});
}, (e) => {
res.status(400).send(e);
console.log('Unable to get clients', e);
})
});
I know that I'm likely doing something completely wrong but I don't know where I need to look for my mistake. Please help!

I would check if the client exist before adding a transaction. A transaction needs a client first.
Forewarn, I'm not a fan of then and catch so this answer does not use it. I normally use async.js when dealing with multiple asynchronous operations.
Anyways, I would do it like
app.post('/clients/:id/transactions', authenticate, (req, res) => {
Client.findOne({ _id: req.params.id }, (err, client) => {
if (err)
return res.status(400).send(err);
if (!client)
return res.status(400).send(new Error('No client'));
Transaction.create({
amount: req.body.amount,
date: new Date(), // I don't think you need .getTime()
total: req.body.total,
_creator: client._id
}, (err, transaction) => {
if (err)
return res.status(400).send(err);
client.transactions.push(transaction._id);
client.save(err => {
if (err)
return res.status(400).send(err);
res.json(transaction);
});
});
});
});
Good idea to also turn on debugging mode to see your queries: mongoose.set('debug', true).
You might also find using timestamps option for Transaction schema more useful than explicitly using date field
To get clients with their transactions
app.get('/clients', authenticate, (req, res) => {
Client.find({ _creator: req.user._id }).populate('transactions').exec((err, clients) => {
if (err)
return res.status(400).send(err);
res.json(clients);
});
});

so first of all i don't exactly know what _creator key in Client model representing, it's probably user identifier who has some clients, but if I'm wrong please correct me.
Honestly I don't know why you are making two way document connection, (keeping client in transactions, and also keeping transactions in clients) in my opinion first option is better for mongodb and using that you can easily get transaction's list with find, or mongodb aggregation, but you can't get data using populate.
In second option you need to remember that one document could have maximum 16MB. And also keeping thousands of transactions in one array is not well for performance. Think about example that you have 5000 transaction and you want to show list with pagination (50 records per page), with array option you have to get whole document, and splice array to 50 records. In first option you could use mongodb skip and limit. Please think about it.
Returning to question, mistake you are doing is here:
transaction.save().then((doc) => {
Client.findOneAndUpdate({
_id: id,
_creator: req.user._id,
transactions: req.body.transaction
});
res.send(doc);
Here you don't exactly say how this document should have to updated about.
Mongoose in method findOneAndUpdate using mongodb findAndModify method. But params are used from update.
https://docs.mongodb.com/manual/reference/method/db.collection.update/
And also documentation says that you what params like:
Query#findOneAndUpdate([query], [doc], [options], [options.passRawResult], [options.strict], [callback])
So first query param is mongo query to find one document in database, next param is object with updating query, and after that you could send some additional options in third param. So your code should looks like this:
transaction.save().then((doc) => {
Client.findOneAndUpdate({
_id: id,
_creator: req.user._id,
}, {
$addToSet: {
transactions: doc._id,
}
});
res.send(doc);
You could use addToSet or push both are putting element into array, but addToSet avoiding duplicates in array. And as you se we push new transaction identifier into this array. And after all you only populate transaction key.
I hope I helped. If you have any questions please ask.