Node Express.js Middleware, end Response - node.js

validateRegister: async (req, res, next) => {
UserModel.findOne({email:req.body.email}, (err, example) => {
console.log(example);
if(err) console.log(err);
if(example) {
res.status(400).json({message: "Email already registered!"});
res.end() //next('route')
}
});
console.log("test");
const user = new UserModel(req.body);
await user.save((err) => {
if (err) return res.status(500).json({ message: "Database issue!" });
});
next();
},
Ok, I tried to insert user data if it is not already in the database using mongoose. If the User regarding the email is already in the database the response should be ended and the user not inserted. I tried to end the response with res.end() and next('route'), but nothing seems to work, the console.log("test") still runs.
Error:
events.js:353
throw er; // Unhandled 'error' event
^
Error [ERR_HTTP_HEADERS_SENT]: Cannot set headers after they are sent to the client
at ServerResponse.setHeader (_http_outgoing.js:561:11)
Thanks for your help

Code below callback function gets executed before callback gets completed and multiple res.send happened.
you can try this
validateRegister: async (req, res, next) => {
UserModel.findOne({ email: req.body.email }, (err, example) => {
console.log(example);
if (err) {
console.log(err);
return res.status(500).json({ message: "Something went wrong" });
}
if (example) {
return res.status(400).json({ message: "Email already registered!" });
}
console.log("test");
const user = new UserModel(req.body);
await user.save((err) => {
if (err) return res.status(500).json({ message: "Database issue!" });
});
});
next();
}
Or
validateRegister: async (req, res, next) => {
try {
let example = await UserModel.findOne({ email: req.body.email });
console.log(example);
if (example)
return res.status(400).json({ message: "Email already registered!" });
console.log("test");
const user = new UserModel(req.body);
await user.save((err) => {
if (err) return res.status(500).json({ message: "Database issue!" });
});
next();
} catch (err) {
console.log(err);
return res.status(500).json({ message: "Something went wrong" });
}
}

you can add return before returning response in the case of user email already found.
What seems to happen is that your program is calling res two times

Related

Why do I get this error : Error [ERR_HTTP_HEADERS_SENT]: Cannot set headers after they are sent to the client

I am trying to create a simple registration using passsport-local and passport-jwt modules using the following code as my reister root/controller:
var passport = require('passport');
const User = require('../model/User');
const handleNewUser = async (req, res) => {
const { email, password } = req.body;
if (!email || !password) return res.status(400).json({ 'message': 'Username and password are required.' });
// check for duplicate usernames in the db
const duplicate = await User.findOne({ email: email }).exec();
if (duplicate) return res.sendStatus(409); //Conflict
try {
const result = User.register(new User({username : req.body.email}), req.body.password, (err , user) => {
if (err) {
res.statusCode(500);
res.setHeader('Content-Type', 'application/json');
res.json({ err: err });
} else {
console.log('success');
passport.authenticate('local')(req, res, () => {
res.statusCode = 200;
res.setHeader('Content-Type', 'application/json');
res.json({ success: true, status: 'Registration Successful' });
});
}
});
console.log(result);
res.status(201).json({ 'success': `New user ${user} created!` });
} catch (err) {
res.status(500).json({ 'message': err.message });
}
}
module.exports = { handleNewUser };
And this is the error I do get:
POST /register
undefined
node:internal/errors:465
ErrorCaptureStackTrace(err);
^
Error [ERR_HTTP_HEADERS_SENT]: Cannot set headers after they are sent to the client
And it happens here:
res.setHeader('Content-Type', 'application/json');
I don't know why do I get this error message and how can I fix it?

can't set status of 400 in express

I have a simple web service and it has a route for register user ,
I want when email exists in DB throw an error with status of 400 or other
I've done it like this
controllers/user.js
const { User } = require('../models/user')
exports.create = async (req, res) => {
try {
const { email } = req.body
const user = await User.findOne({ email })
if (user) {
return res.json({ err: 'email already exists' })
}
await User.userValidation(req.body)
await User.create(req.body)
return res.json({})
} catch (err) {
res.status(400).send({ err })
}
}
BUT , it always give status of 200,
where is the problem ?
Add the status to your response:
if (user) {
return res.status(400).json({ err: 'email already exists' })
}
You can simply send the status 400 when checking if(user)
if(user){
res.status(400).jsom({ err: "Email already exists" });
}
OR
Threat the errors and add a middleware using next (a little bit more complicated then the first one, but more proffessional)
exports.create = async (req, res, next) => {
try {
const { email } = req.body
const user = await User.findOne({ email })
if (user) {
throw new Error("Email already exists");
}
await User.userValidation(req.body)
await User.create(req.body)
return res.json({})
} catch (err) {
next(err, req, res, next);
}
}
In the next middleware you can threat the error and send whatever response you need. (err, req, res objects are sent like references, so you can use them there)

error 'user.findOneAndUpdate is not a function' but data updated

i'm trying to use findOneAndUpdate for change password on mongoose, it's work, database updated
but error message show
"error": "user.findOneAndUpdate is not a function"
this my routes
router.post('/changepass', async (req, res) => {
const { phone, password } = req.body;
try {
const user = await User.findOneAndUpdate({phone},{password})
await user.findOneAndUpdate();
res.send({ user });
} catch (err) {
console.log(err)
res.status(422).send({ error: err.message });
}
});
and this my userSchema
userSchema.pre('findOneAndUpdate', function(next) {
const update = this.getUpdate()
bcrypt.genSalt(10, (err, salt) => {
bcrypt.hash(update.password, salt, (err, hash) => {
this.getUpdate().password = hash;
return next();
})
})
});
please help me, i'm stuck for hours on this
try removing this line await user.findOneAndUpdate(); This line is causing the error and as per official docs it should be not there
router.post('/changepass', async (req, res) => {
const { phone, password } = req.body;
try {
const user = await User.findOneAndUpdate({phone},{password})
res.send({ user });
} catch (err) {
console.log(err)
res.status(422).send({ error: err.message });
}
});
here is doc reference - https://mongoosejs.com/docs/tutorials/findoneandupdate.html

Create USER with bcrypt and authenticate

This is my user.js file, where i handle two requestes.
First the POST /signup, where the user enters an email, and a password so that i can store it in mongodb.
var express = require("express");
const router = express.Router();
const mongoose = require("mongoose");
var bcrypt = require("bcrypt");
var jwt = require("jsonwebtoken");
var User = require("../models/user");
router.post("/signup", (req, res, next) => {
User.find({ email: req.body.email })
.exec()
.then(user => {
if (user.length >= 1) {
return res.status(409).json({
message: "Mail exists"
});
} else {
bcrypt.hash(req.body.password, 10, (err, hash) => {
if (err) {
return res.status(500).json({
error: err
});
} else {
const user = new User({
_id: new mongoose.Types.ObjectId(),
email: req.body.email,
password: hash
});
user
.save()
.then(result => {
console.log(result);
res.status(201).json({
message: "User created"
});
})
.catch(err => {
console.log(err);
res.status(500).json({
error: err
});
});
}
});
}
});
});
Second the POST /login, where the user enters an email, and the password and with bcrypt i compare if the password matches the one in the db.
router.post("/login", (req, res, next) => {
User.find({ email: req.body.email })
.exec()
.then(user => {
if (user.length < 1) {
return res.status(401).json({
message: "Auth failed"
});
}
bcrypt.compare(req.body.password, user[0].password, (err, result) => {
if (err) {
return res.status(401).json({
message: "Auth failed"
});
}
if (result) {
const token = jwt.sign(
{
email: user[0].email,
userId: user[0]._id
},
process.env.JWT_KEY,
{
expiresIn: "1h"
}
);
return res.status(200).json({
message: "Auth successful",
token: token
});
}
res.status(401).json({
message: "Auth failed"
});
});
})
.catch(err => {
console.log(err);
res.status(500).json({
error: err
});
});
});
The problem is the following: Whenever i try to create a user /signup using postman the request stays in "loading" and the server shuts down.
POSTMAN body: {
'emial': 'teste#gmail.com',
'password': '12345'
}
Error in the server:
UnhandledPromiseRejectionWarning: MongoNetworkError: failed to connect to server [node-rest-shop-shard-00-01-pbcph.azure.mongodb.net:27017] on first connect [MongoNetworkError: connection 4 to node-rest-shop-shard-00-01-pbcph.azure.mongodb.net:27017 timed out]
(node:1496) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). (rejection id: 1)
(node:1496) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.
The User.find promise is being rejected because Node fails to connect to your MongoDB instance. This rejected promise tries to execute the first error handler that it comes across. In your case, it fails to find any catch() to handle this error. You can avoid this by adding a catch() to the promise chain at the end.
You should also look into why your Node instance cannot make a successful connection to your MongoDB instance.
router.post("/signup", (req, res, next) => {
User.find({ email: req.body.email })
.exec()
.then(user => {
if (user.length >= 1) {
return res.status(409).json({
message: "Mail exists"
});
} else {
bcrypt.hash(req.body.password, 10, (err, hash) => {
if (err) {
return res.status(500).json({
error: err
});
} else {
const user = new User({
_id: new mongoose.Types.ObjectId(),
email: req.body.email,
password: hash
});
user
.save()
.then(result => {
console.log(result);
res.status(201).json({
message: "User created"
});
})
.catch(err => {
console.log(err);
res.status(500).json({
error: err
});
});
}
});
}
}).catch(err => { //Handle the error here.
console.log(err);
res.status(500).json({
error: err
});
});
});
You should do the same for your login call.

Keep getting "Can't set headers after they are sent" using Node/Express

I keep getting "Can't set headers after they are sent" building a Node/Express API.
The issue is I am not setting the headers after the response has been sent anywhere. I am always calling res.status(xxx).json({}) to close ever condition.
Route
const router = require('express').Router();
router.get('/password/validate/:hash', PasswordController.validate);
router.post('/password/update', PasswordController.update);
Controller
This is where the error is occurring. I am calling the validate request specifically.
// Import node packages
const mongoose = require('mongoose');
const Password = require('../models/password');
const User = require('../models/user');
const bcrypt = require('bcryptjs');
const moment = require('moment');
const string = require('../middleware/string_functions')
exports.update = (req, res, next) => {
User.findOne({ email: req.body.email })
.exec()
.then(user => {
if (!user) {
res.status(401).json({
message: 'Cannot retrieve account'
})
}
const expiry = moment().add(30, 'seconds');
const unique_string = string.generate_random(32);
const url_hash = string.base64_encode(unique_string +':'+ user._id);
bcrypt.hash(unique_string, 10, (err, hash) => {
if (err) {
res.status(500).json({
error: err.message
})
}
const query = { user_id: user._id }
const newData = {
hash,
expiry
}
Password.findOneAndUpdate(query, newData, { upsert: true, new: true })
.exec()
.then(request => {
res.status(201).json({
message: 'success',
url: 'localhost:8081/users/password/validate/' + url_hash,
data: request
})
})
.catch(err => {
res.status(500).json({
error: err.message
})
})
})
})
.catch(err => {
res.status(500).json({
error: err.message
})
})
}
exports.validate = (req, res, next) => {
if (!req.params.hash) {
res.status(500).json({
error: 'Missing hash'
})
}
const data = string.base64_decode(req.params.hash).split(':');
console.log(data)
Password.findOne({ user_id: data[1] })
.exec()
.then(request => {
if (!request) {
res.status(404).json({
message: 'Change request not found or expired'
})
}
bcrypt.compare( data[0], request.hash, (err, result) => {
if (err) {
res.status(500).json({
error: err.message
})
}
if (result) {
if (moment().isAfter(request.expiry)) {
res.status(401).json({
message: 'Time has expired'
})
}
res.status(200).json({
message: 'Hash validation successful'
})
}
res.status(500).json({
error: 'Something went wrong'
})
})
})
.catch(err => {
res.status(500).json({
error: err.message
})
})
}
Console Error
_http_outgoing.js:494
throw new Error('Can\'t set headers after they are sent.');
^
Error: Can't set headers after they are sent.
at validateHeader (_http_outgoing.js:494:11)
at ServerResponse.setHeader (_http_outgoing.js:501:3)
at ServerResponse.header (/Users/chrislloyd/Development/Projects/happy-hour-api/node_modules/express/lib/response.js:767:10)
at ServerResponse.send (/Users/chrislloyd/Development/Projects/happy-hour-api/node_modules/express/lib/response.js:170:12)
at ServerResponse.json (/Users/chrislloyd/Development/Projects/happy-hour-api/node_modules/express/lib/response.js:267:15)
at bcrypt.compare (/Users/chrislloyd/Development/Projects/happy-hour-api/api/controllers/passwords.js:83:22)
at /Users/chrislloyd/Development/Projects/happy-hour-api/node_modules/bcryptjs/dist/bcrypt.js:297:21
at /Users/chrislloyd/Development/Projects/happy-hour-api/node_modules/bcryptjs/dist/bcrypt.js:1353:21
at Immediate.next [as _onImmediate] (/Users/chrislloyd/Development/Projects/happy-hour-api/node_modules/bcryptjs/dist/bcrypt.js:1233:21)
at runCallback (timers.js:789:20)
at tryOnImmediate (timers.js:751:5)
at processImmediate [as _immediateCallback] (timers.js:722:5)
Updated Example
exports.update = (req, res, next) => {
// Check if hash value exists
if (!req.params.hash) {
res.status(500).json({
error: 'Missing hash value'
});
return;
}
// Check if password and confirmation are the same
if (req.body.password != req.body.passwordConfirmation) {
res.status(401).json({
message: 'Password confirmation does not match'
});
return;
}
// Decode and split hash and user id into array
const data = string.base64_decode(req.params.hash).split(':');
// Find record that contains user id
Password.findOne({ user_id: data[1] })
.exec()
.then(request => {
console.log(request)
// Throw 404 error if record is not found
if (!request) {
return res.status(404).json({
message: 'Password change request doest not exist or timed out'
});
}
// Check if change request has expired
if (moment().isAfter(request.expiry)) {
res.status(401).json({
message: 'Password change request expired',
request: {
request: 'http://localhost:3001/users/password/request'
}
});
// Delete expired record
Password.remove({ _id: request._id })
.exec()
.catch(err => {
res.status(500).json({
error: err.message
});
});
return;
}
// Compare hash value from encoded string to encrypted hash value in database
console.log(mongoose.Types.ObjectId(request.user_id))
bcrypt.compare( data[0], request.hash, (err, result) => {
// Bcrypt error performing comparison
if (err) {
res.status(500).json({
error: err.message
});
return;
}
// Check if result is true
if (result) {
// Find user record matching request.user_id and update password
User.findOneAndUpdate({ _id: mongoose.Types.ObjectId(request.user_id) }, {$set: { password: req.body.password }}, {new: true}, (err, user) => {
console.log(user)
// Error finding and updating user record
if (err) {
res.status(500).json({
error: err.message
});
return;
}
// If returned user account is not null
if (user) {
res.status(200).json({
message: 'Password updated',
user
});
return;
}
// Could not find user record
res.status(404).json({
message: 'Could not find user account to update'
});
return;
})
}
// Catch all error
res.status(500).json({
error: 'Something went wrong'
});
return;
})
})
.catch(err => {
res.status(500).json({
error: err.message
});
return;
});
}
That particular error is caused when you send multiple responses to the same request.
You see to be thinking that as soon as you do res.status(...).json(...) that your function returns and stops executing. It does not. res.json() is just a regular function call. It doesn't change the control flow in your function at all (unless it throws an exception). A successful call to res.json() executes and then your function just keeps right on executing the lines of code that follow.
What you need is a return statement after each time you send a response (if there is any other code in your function that could execute and send another response) so that your function doesn't continue to execute and send another response or you could bracket your responses in if/else statements so you don't execute the sending of more than one response.
Here's a fixed version with 5 added return statements to keep the rest of your code from executing after you've sent a response and to keep you from sending multiple responses to the same request. Each addition is commented with ==> added:
// Import node packages
const mongoose = require('mongoose');
const Password = require('../models/password');
const User = require('../models/user');
const bcrypt = require('bcryptjs');
const moment = require('moment');
const string = require('../middleware/string_functions')
exports.update = (req, res, next) => {
User.findOne({ email: req.body.email })
.exec()
.then(user => {
if (!user) {
res.status(401).json({
message: 'Cannot retrieve account'
})
return; // <== added
}
const expiry = moment().add(30, 'seconds');
const unique_string = string.generate_random(32);
const url_hash = string.base64_encode(unique_string +':'+ user._id);
bcrypt.hash(unique_string, 10, (err, hash) => {
if (err) {
res.status(500).json({
error: err.message
})
return; // <== added
}
const query = { user_id: user._id }
const newData = {
hash,
expiry
}
Password.findOneAndUpdate(query, newData, { upsert: true, new: true })
.exec()
.then(request => {
res.status(201).json({
message: 'success',
url: 'localhost:8081/users/password/validate/' + url_hash,
data: request
})
})
.catch(err => {
res.status(500).json({
error: err.message
})
})
})
})
.catch(err => {
res.status(500).json({
error: err.message
})
})
}
exports.validate = (req, res, next) => {
if (!req.params.hash) {
res.status(500).json({
error: 'Missing hash'
})
}
const data = string.base64_decode(req.params.hash).split(':');
console.log(data)
Password.findOne({ user_id: data[1] })
.exec()
.then(request => {
if (!request) {
res.status(404).json({
message: 'Change request not found or expired'
})
return; // <== added
}
bcrypt.compare( data[0], request.hash, (err, result) => {
if (err) {
res.status(500).json({
error: err.message
})
return; // <== added
}
if (result) {
if (moment().isAfter(request.expiry)) {
res.status(401).json({
message: 'Time has expired'
})
}
res.status(200).json({
message: 'Hash validation successful'
})
return; // <== added
}
res.status(500).json({
error: 'Something went wrong'
})
})
})
.catch(err => {
res.status(500).json({
error: err.message
})
})
}
The res object by itself does not stop the execution of your program. You must use return if you prefer to use Guard Clauses instead of Nested Conditions
Replace statements like this:
if (err) {
res.status(500).json({
error: err.message
})
}
With this:
if (err) {
res.status(500).json({
error: err.message
});
return; // return statement added
}

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