Develop Reference

How can I remove bookmarked posts of user (1) from user (2) tab after user (1) deletes his account?

After creating a node.js, express, mongoDb REST api for a social media web app with almost all basic social media actions (login, signup, add a post, delete a post, delete account, follow users ...),
I'm currently facing a problem, where after implementing bookmarking a post feature, I'm unable to come up with a solution to remove a bookmarked post from another user's bookmarked posts page, after the first user deletes his account. I'll provide my code below:
(P. S. Bookmarks is an array inside User model. I'd also like to mention the steps that I initially intended for the task:
Get current user by ID
Then get all posts created by this user, which returns an array, so I mapped it to get each Posts id
After that I fetched all users accross the app, and initially intended to compare the posts that live inside bookmarks array inside each user to the posts that the current user have created. Then I'd pull these same posts out of the bookmarks array from each of these users.
--> I think the logic that I've analyzed is maintainable, but it's just not working with me. This is the Code below:
export const deleteUser = async (req, res) => {
try {
let user = await User.findById(req.params.userId)
const userPosts = await Post.find({ creatorId: user._id })
const allUsers = await User.find()
const myPostsIds = userPosts.map((post) => post._id.toString())
//This is the section I've implemented for my task, but obviously
something isn't right
await Promise.all(
myPostsIds.forEach((id) =>
allUsers.map((user) => {
user.bookmarks.includes(id) &&
user.updateOne({ $pull: { bookmarks: id } })
})
)
)
await Post.deleteMany({ creatorId: user._id })
await user.remove()
res.status(200).json({
message: "Account has been deleted successfully!",
})
} catch (err) {
errorHandler(res, err)
}
}

As mentioned in my comments, the value you pass to Promise.all is no array of Promise/array of async functions.
The 2nd error is inside the (currently) forEach function at the .map() you are not returning anything in the map-call.
So this should do it:
// first convert all ids to a promise
await Promise.all(myPostsIds.map(id => new Promise(resolve => {
// during this, await every test and update
return Promise.all(allUsers.map(user => new Promise(resolve => {
// if it includes the id, cast the update and then resolve
if (user.bookmarks.includes(id)) {
// if found, resolve the promise for this user after the change
user.updateOne({ $pull: { bookmarks: id } }).then(resolve)
} else {
// resolve directly if not found.
resolve()
}
// when all users are done for this id, resolve the Promise for the given id
}))).then(resolve)
})))
An easier to read and shorter method would be:
for (const id of myPostIds) {
for (const user of allUsers) {
if (user.bookmarks && user.bookmarks.includes(id)) {
await user.updateOne({ $pull: { bookmarks: id } });
}
}
}

Show user invoices for simultaneously logged in users using Expressjs

I have created a simple invoice application using the MERN stack. The application is great at handling data for the logged in user as long as one user is logged in, but if another user logs in then the invoices for the user that first logged in is shown.
I am currently using app.set() and app.get() to pass data between endpoints and send to my frontend client. Auth0 handles the authentication layer, but would express-session solve this issue? And if it is how would I go about implementing this? Or is there a better solution?
Below is the code that sends the invoices currently to the frontend:
var express = require('express');
var app = express();
var userInvoices = express.Router();
const axios = require('axios');
const InvoiceModel = require('../models/Invoice');
const UserModel = require('../models/User');
//Functions//
async function clientCall() {
const url = `${process.env.REACT_APP_SAVE_USER}`;
const axiosConfig = {
method: 'get',
url
};
await axios(axiosConfig).catch((e) => {console.log(e)});
};
async function fetchUsersFromDB() {
const usersFromDB = await UserModel.find().catch((e) => {console.log(e)});
return usersFromDB;
};
async function saveUser(User) {
const condition = {email: User.email};
const query = {
nickname: User.nickname,
name: User.name,
picture: User.picture,
email: User.email,
email_verified: User.email_verified,
sub: User.sub,
};
const options = { upsert: true };
const update = await UserModel.updateMany(condition, query, options).catch((e) => {console.log(e)});
// Log the amount of documents that where updated in the DB.
if(update.nModified > 0 ) {
console.log('Number of Users added or updated to DB:', update.nModified)
}
};
function findCommonUser(dbUser, User) {
if(dbUser.length <= 0) {
UserModel.create(User, () => {console.log('Users saved to database')});
console.log('An Error has occured with Database')
} else {
dbUser.forEach((DBElement) => {
if(User.email !== DBElement.email) {
saveUser(User);
}
})
}
console.log(' Users match')
};
function matchUserAndInvoice(dbInvoices, loggedInUser) {
let newArray = [];
dbInvoices.forEach(async (DBElement) => {
if(DBElement.customer_email === loggedInUser.email){
newArray.push(DBElement);
app.set('userInvoices', newArray);
}
})
}
// prevents user from having to refresh to get data.
clientCall();
userInvoices.post('/saveUser', async (req, res) => {
try {
const User = req.body;
const usersFromDB = await fetchUsersFromDB().catch((e) => {console.log(e)});
findCommonUser(usersFromDB, User);
app.set('Users', User)
} catch (error) {
console.log(error)
}
})
userInvoices.get('/fetchUserInvoices', async (req,res) => {
try {
const invoices = await InvoiceModel.find().catch((e) => {console.log(e)});
const user = await app.get('Users');
await matchUserAndInvoice(invoices,user);
const userInvoices = await app.get('userInvoices')
res.json(userInvoices);
} catch (error) {
console.log(error)
}
});
;
module.exports = userInvoices;

app.get() is essentially global to your server instance so putting data there to use between requests for individual users will (as you have discovered) get data confused between different users as all users are trying to store data in the same place.
The usual way to solve a problem like this is to use express-session. This cookies the end-user's connection the first time they connect to your server and then creates a server-side object that is automatically associated with that cookie. Then, inside of any request handler, you can read or set data in req.session and that data will uniquely belong to just that user.
If the user changes devices or clears their cookies, then the association with the session object for that user will be lost (creating a new session object for them upon their next connection). But, if you have a persistent data store and you use some sort of login that allows you to populate the session from the user's persistent store, you can even make the session persistent across devices for the same user (though often times this is not required).
In the specific application you describe in your question (tracking invoices), it seems like your invoice data should be tagged with a specific user when it is stored in your database and then any future requests to display invoices should query based on the particular user that is making the request. This requires a login and login cookie so that you can uniquely identify each user and thus show them only the invoices that pertain to them.
The above-described session object should only be used for temporal session state, not for persistent storage such as invoices. If your server implementation is truly RESTFUL, you may not even need any data stored in the session object other than user's logged in userID.

Mongoose: save() is not a function when using find() and atributing value to variable

This is the basic structure of the Schema I am working with using mongoose:
const User = {
uid: {
type: String
},
routes: {
type: Array
}
}
In my application there is a POST to /route, in which uid and a new route are provided as "body parameters". In order to add to the routes array, I wrote a code similar to this (the only diference is that I check if the route already exists):
var user = await User.find({uid: uid}) // user is found, as expected
user[0].routes.push(route //parameter)
user.save()
When a POST request is made, though, it throws an error:
TypeError: user.save is not a function
What am I doing wrong?

user in your code is an array of documents
so you'll have mongo documents inside that array
you can't do array.save, you've to do document.save
await user[0].save()
var user = await User.find({uid: uid}) // user is found, as expected
if (user && user.length) {
user[0].routes.push(route //parameter)
await user[0].save(); // save the 1st element of the object
}
if your query returns only 1 record better use https://mongoosejs.com/docs/api.html#model_Model.findOne
var user = await User.findOne({uid: uid}) // user is found, as expected
if (user) {
user.routes.push(route //parameter)
await user.save(); // save the 1st element of the object
}

if you need to find only one specific user you should use findOne function instead
User.findOne({uid: uid})
.then(
(user) => {
user[0].routes.push(route //parameter);
user.save();
},
(err) => {
console.error(err);
}
)

I think bulkSave() can be what you're looking for:
var user = await User.find({uid: uid}
enter code user[0].routes.push(route //parameter)
await User.bulkSave(user)

TypeError: Cannot set property 'user' of undefined<br> at [file path] sqlite3

I am receiving an undefined error when attempting to set a session for the user upon validation of credentials on login. I am trying to use express-session to create the session for the user but do not have it directly imported into the file (I was guided to not do so) but am unsure how to resolve this error given. Any help and insight would be much appreciated!
End point:
router.post("/login", async (req, res, next) => {
try {
const { username, password } = req.body
// * checks for record existence in db, assigns record to var for access
const user = await users_access.findByFilter({ username })
if (!user) {
return res.status(401).json({ message: 'invalid crededentials' });
}
// * compares the entered password to the hash on record
const passwordValid = await secure.compare(password, user.password)
// * handling invalid responses + creating session
if (!passwordValid) {
return res.status(401).json({ message: 'invalid credentials' });
}
req.session.user = user
res.json({ message: `welcome, ${user.username}!`})
} catch(error) {
next(error)
}
});
application model:
// * add users to the datbase
// * inserts argument into user table in db access
// * returns a user found by id
const add = async (user) => {
const [id] = await database_access("users")
.insert(user)
return findById(id)
}
// * find user record with username and password
const find = () => {
return database_access("users").select("id", "username")
}
// * find user by filter
const findByFilter = (filter) => {
return database_access("users")
.select("id", "username", "password")
.where(filter)
.first()
}
// * find user with id
const findById = (id) => {
return database_access("users")
.select("id", "username")
.where({ id }) // desctructuring id from the request
.first()
}
module.exports = {
add,
find,
findByFilter,
findById
}
if you need to see any additional code to assess I am happy to provide but believe this is the source of issue per the error response. Thank you in advanced!

so I guess you are using the express-session module in your entry file for the server, app.js, server.js, index.js however you call it.
this login handler require to be used in a context where the session is available.
I think what you want is not a unit test for this particular router, but an integration test, to test this router in the context of your app.
This is all I can see from the information you provided. If this was not helpful enough, maybe you can show us your servers main file. and how this router is used.

How do I query Firebase using Typescript?

I have push notifications set up for my app using Firebase Cloud Functions. It works well. Now I want to update the app's badge count as part of the push notification. I've read that the only way to do that is via server-side code; I can't do it locally.
So I'm trying to get the number of new users from the server and then use that number as the badge count when I send the push notification, but I can't figure out how to go about it. I've spent three days on this and now I'm hoping someone can point me in the right direction.
I'm using Firebase functions and Typescript (with VSCode). My course of action is to:
get list of userIDs from 'admin' node
iterate over those userIDs on 'user' node to query if user's 'newUser' parameter is true
append those results to an array
count the array and then send that to the badge on push notification
My 'users' database structure is like so:
"users": {
"2NBvNgdNRVe3nccTEDts2Xseboma": {
"email": "someone#someone.com"
"newUser": "true",
"referral": "none",
...
},
"hjC6os6wzIV1FyULmGxalU3fM7ef": {
"email": "someoneElse#someone.com"
"newUser": "false",
"referral": "Bennett",
...
}
And my 'admin' database is structured like so:
"admin": {
"2NBvNgdNRVe3nccTEDts2Xseboma": {
"email": "someone#someone.com"
"familyName": "Someone",
"memberSince": "1529119893",
},
"hjC6os6wzIV1FyULmGxalU3fM7ef": {
"email": "someoneElse#someone.com"
"familyName": "Someone Else",
"memberSince": "1529125722",
...
}
Here is my feeble attempt to code this:
exports.getNewUserCount =
functions.database.ref('/users/{userID}/newUser')
.onUpdate((snapshot, _context) => {
console.log('test 2')
// Get a database reference
const db = admin.database();
const ref = db.ref('admin');
return ref.once('value', function(adminSnap) {
const userData = adminSnap.val()
console.log('admin key:', adminSnap.key)
console.log('user data:', userData)
})
});
Right now I'm stuck on retrieving the list of users from the admin node (my step #1 above).
UPDATE
I finally got a list of the users as a snapshot, but I can't figure out how to iterate over them. How do I turn the snapshot into an array of the user keys?
And then once I get the list of user keys, then how do I use that to iterate over the 'users' node to get the list of new users (my step #2 above)?
And then how to put those new users into an array (my step #3 above), and then get the number of new users for the 'badge' parameter when I send my push notification (my step #4 above)?
The problem is that this seems really inefficient. There has to be a better way to simply get a list of new users. There has to be some sort of query I can perform that will go over my 'users' node, see which ones have 'true' for their 'newUser' node, and get a count of those--instead of my roundabout way of getting a list of user from 'admin' node, then using that list to get a list of 'new users' from the 'users' node, then creating an array and then counting that array, then using that number to send to the 'badge' parameter on my push notification.
Any thoughts? I've been at this for days.
If it helps, I know Swift and the app is iOS. Thanks!!
UPDATE #2
So I opted to try and just get a snapshot of all users and bypass the 'admin' node altogether. Here is the code:
const db = admin.database();
const ref = db.ref('users');
return ref.once('value').then((adminSnap) => {
console.log('admin key:', adminSnap.key)
// create blank array to store
let newUserCount = 0;
// iterate over adminSnap to get each individual snap
adminSnap.forEach(function (userSnap) {
const userData = userSnap.val();
const userKey = userSnap.key
// console.log('email?', userData.email, 'user key:', userKey, 'new user?', userData.newUser)
if (userData.newUser === true) {
newUserCount++
console.log('new user:', userKey, userData.newUser, userData.email)
}
});
console.log(newUserCount)
})
This new code works and gives me the number for my badge parameter for when I perform my push notification, but I'm wondering if it's the most efficient way to do things. Plus, as my database grows in size, won't it tax the server / slow way down? And won't it cost me a lot of bandwidth for my Firebase account?
I thought this would be a simple thing to do, but it's turning into a bit of a hassle. I'm open to a different way to complete this. Thanks!

After even more research, I ended up abandoning my original approach. I decided to just create a new node on my Firebase database with the new user count and then update it via code from elsewhere. It's the simplest approach and will use the least amount of bandwidth.
Here is my final code:
function sendAlertToiPhone() {
console.log('test E')
// Get a database reference
const db = admin.database();
const ref = db.ref('stats');
ref.child('newUserCount').once('value').then((snapshot) => {
const newUserCount = snapshot.val()
console.log('new user count:', newUserCount)
// send to Phontaine's iPhone 6
const FCMToken = "blahbehtyblahblah"
const payload = {
notification: {
title: 'New User',
body: 'Moneypants has a new download.',
sound: 'default',
badge: String(newUserCount)
}
};
return admin.messaging().sendToDevice(FCMToken, payload)
.then(function (response) {
console.log("Successfully sent message:", response);
})
.catch(function (error) {
console.log("Error sending message:", error);
});
}).catch(function (err) {
console.log('new user count error:', err);
})
}