Mi código funcionaba inicialmente, pero no sé por qué dejó de funcionar y me dio este error:

 MongooseError: Operation `users.findOne()` buffering timed out after 10000ms at Timeout.<anonymous> (/Users/nishant/Desktop/Yourfolio/backend/node_modules/mongoose/lib/drivers/node-mongodb-native/collection.js:184:20) at listOnTimeout (internal/timers.js:549:17) at processTimers (internal/timers.js:492:7)

Estoy tratando de autenticar al usuario iniciando sesión con JWT. Mi cliente funciona bien, pero en mi backend aparece este error. Mi código de fondo:

 import neuron from '@yummyweb/neuronjs' import bodyParser from 'body-parser' import cors from 'cors' import mongoose from 'mongoose' import emailValidator from 'email-validator' import passwordValidator from 'password-validator' import User from './models/User.js' import Portfolio from './models/Portfolio.js' import bcrypt from 'bcryptjs' import jwt from 'jsonwebtoken' import auth from './utils/auth.js' // Dot env import dotenv from 'dotenv' dotenv.config() // Custom Password Specifications // Username Schema const usernameSchema = new passwordValidator() usernameSchema.is().min(3).is().max(18).is().not().spaces() // Password Schema const passwordSchema = new passwordValidator() passwordSchema.is().min(8).is().max(100).has().uppercase().has().lowercase().has().digits().is().not().spaces() const PORT = process.env.PORT || 5000 const neuronjs = neuron() // Middleware neuronjs.use(bodyParser()) neuronjs.use(cors()) // Mongoose Connection mongoose.connect(process.env.MONGO_URI, { useNewUrlParser: true }, () => console.log("MongoDB Connected")) // API Routes neuronjs.POST('/api/auth/signup', async (req, res) => { const { username, email, password, passwordConfirmation } = req.body // Validation: all fields are filled if (!username || !email || !password || !passwordConfirmation) { return res.status(400).json({ "error": "true", "for": "fields", "msg": "fill all the fields" }) } // Validation: username is valid if (usernameSchema.validate(username, { list: true }).length !== 0) { return res.status(400).json({ "error": "true", "for": "username", "method_fail": usernameSchema.validate(username, { list: true }), "msg": "username is invalid" }) } // Validation: email is valid if (!emailValidator.validate(email)) { return res.status(400).json({ "error": "true", "for": "email", "msg": "email is invalid" }) } // Validation: password is valid if (passwordSchema.validate(password, { list: true }).length !== 0) { return res.status(400).json({ "error": "true", "for": "password", "method_fail": passwordSchema.validate(password, { list: true }), "msg": "password is invalid" }) } // Validation: password is confirmed if (password !== passwordConfirmation) { return res.status(400).json({ "error": "true", "for": "confirmation", "msg": "confirmation password needs to match password" }) } // Check for existing user with email const existingUserWithEmail = await User.findOne({ email }) if (existingUserWithEmail) return res.status(400).json({ "error": "true", "msg": "a user already exists with this email" }) // Check for existing user with username const existingUserWithUsername = await User.findOne({ username }) if (existingUserWithUsername) return res.status(400).json({ "error": "true", "msg": "a user already exists with this username" }) // Generating salt const salt = bcrypt.genSalt() .then(salt => { // Hashing password with bcrypt const hashedPassword = bcrypt.hash(password, salt) .then(hash => { const newUser = new User({ username, email, password: hash }) // Saving the user newUser.save() .then(savedUser => { const newPortfolio = new Portfolio({ user: savedUser._id, description: "", socialMediaHandles: { github: savedUser.username, dribbble: savedUser.username, twitter: savedUser.username, devto: savedUser.username, linkedin: savedUser.username, } }) // Save the portfolio newPortfolio.save() // Return the status code and the json return res.status(200).json({ savedUser }) }) .catch(err => console.log(err)) }) .catch(err => console.log(err)) }) .catch(err => console.log(err)) }) neuronjs.POST('/api/auth/login', async (req, res) => { try { const { username, password } = req.body // Validate if (!username || !password) { return res.status(400).json({ "error": "true", "msg": "fill all the fields", "for": "fields", }) } const user = await User.findOne({ username }) if (!user) { return res.status(400).json({ "error": "true", "msg": "no account is registered with this username", "for": "username" }) } // Compare hashed password with plain text password const match = await bcrypt.compare(password, user.password) if (!match) { return res.status(400).json({ "error": "true", "msg": "invalid credentials", "for": "password" }) } // Create JWT token const token = jwt.sign({ id: user._id }, process.env.JWT_SECRET) return res.json({ token, user: { "id": user._id, "username": user.username, "email": user.email } }) } catch (e) { console.log(e) } }) // Delete a user and their portfolio neuronjs.DELETE("/api/users/delete", async (req, res) => { auth(req, res) const deletedPortfolio = await Portfolio.findOneAndDelete({ user: req.user }) const deletedUser = await User.findByIdAndDelete(req.user) res.json(deletedUser) }) neuronjs.POST("/api/isTokenValid", async (req, res) => { const token = req.headers["x-auth-token"] if (!token) return res.json(false) const verifiedToken = jwt.verify(token, process.env.JWT_SECRET) if (!verifiedToken) return res.json(false) const user = await User.findById(verifiedToken.id) if (!user) return res.json(false) return res.json(true) }) // Getting one user neuronjs.GET("/api/users/user", async (req, res) => { auth(req, res) const user = await User.findById(req.user) res.json({ "username": user.username, "email": user.email, "id": user._id }) }) // Getting the porfolio based on username neuronjs.GET("/api/portfolio/:username", async (req, res) => { try { const existingUser = await User.findOne({ username: req.params.username }) // User exists if (existingUser) { const userPortfolio = await Portfolio.findOne({ user: existingUser._id }) return res.status(200).json(userPortfolio) } // User does not exist else return res.status(400).json({ "error": "true", "msg": "user does not exist" }) } catch (e) { console.log(e) return res.status(400).json({ "error": "true", "msg": "user does not exist" }) } }) // Update Portfolio info neuronjs.POST("/api/portfolio/update", async (req, res) => { auth(req, res) // Find the portfolio const portfolio = await Portfolio.findOne({ user: req.user }) // Then, update the portfolio if (portfolio) { // Call the update method const updatedPortfolio = await portfolio.updateOne({ user: req.user, description: req.body.description, socialMediaHandles: req.body.socialMediaHandles, greetingText: req.body.greetingText, navColor: req.body.navColor, font: req.body.font, backgroundColor: req.body.backgroundColor, rssFeed: req.body.rssFeed, displayName: req.body.displayName, layout: req.body.layout, occupation: req.body.occupation }) return res.status(200).json(portfolio) } }) neuronjs.listen(PORT, () => console.log("Server is running on port " + PORT))

La función del archivo auth.js:

 import jwt from 'jsonwebtoken' const auth = (req, res) => { const token = req.headers["x-auth-token"] if (!token) return res.status(401).json({ "error": "true", "msg": "no authentication token" }) const verifiedToken = jwt.verify(token, process.env.JWT_SECRET) if (!verifiedToken) return res.status(401).json({ "error": "true", "msg": "token failed" }) req.user = verifiedToken.id } export default auth

Cualquier ayuda es muy apreciada y ya probé algunas soluciones, como eliminar node_modules y volver a instalar mongoose.