I'm started working on my very first API using Mongo, Express and Node. When i tried to make API endponit for one specific user, console throw error ReferenceError: err is not defined. An error appears in the method I already used for auth part, and there it worked fine. The part of code where is the error, on line 5:
exports.userById = (req, res, next, id) => {
User.findById(id).exec(() => {
if(err || !user) {
return res.status(400).json({
err: "User not found"
});
}
req.profile = user //adds profile object in req with user info
next();
});
}
Also, the part of code where I tried to get a single user:
exports.getUser = (req, res) => {
req.profile.hashed_password = undefined;
req.profile.salt = undefined;
return res.json(req.profile);
}
I don't think the problem could be here, but there is also route line from routes file
router.get("/users/:userId", authController.requireSignin, userController.getUser);
Thanks everyone for the help!
I'm pretty sure err comes from exec:
User.findById(id).exec(err => {...});
Edit I guess you want to search by id and return something. Try this.
User.findById(id, (err, user) => {
// if error display errort
if(err) console.error(err);
// if user do not exists
if(!user) {// what is user ? the doc result ?
return res.status(400).json({
"err": "User not found" // i think use ""
});
}
req.profile = user //adds profile object in req with user info
next();
});
Related
I have created middleware to validate fields in body, here is how it looks like:
Front-end route:
router.post('/s-i', async (req, res) => {
try {
const { data } = await api.post('/sign-in', req.body)
res.cookie("_rt", data._rt, { httpOnly: true, secure: false })
delete data._rt
return res.json(data)
} catch (e) {
// Here is error
return res.status(e.response.status).json(e.response.data)
}
});
Route (back-end):
router.post('/sign-in', v(['email', 'password', 'twoFa', 'phone']), wrapAsync(userController.signIn));
Middleware:
exports.v = fields => {
return (req, res, next) => {
fields.forEach(field => {
if (req.body[field]) {
const result = require(`./validators/${field}`)(req.body[field])
if (!result)
return res.status(400).json({ message: 'bad-request', status: 400 })
}
})
next()
}
}
In the place where comment is placed I can see this error, actually, everything works find, and if there is wrong field in body front will receive 400 status code, but in back-end terminal I still have this error and can't get why.
The problem is I still keep getting this ERR_HTTP_HEADERS_SENT error. I know the reason of this problem - for example - if you are trying do res.send({}) twice, but I don't really see the reason of problem in this case.
The return res.status(400)... statement returns only from the inner function fields.forEach(field => {...}), but you must return from the middleware function, otherwise the next() will invoke subsequent middlewares after the .json output, leading to the observed error.
You can achieve this by replacing fields.forEach(field => {...}) with
for (var field of fields) {
if (req.body[field]) {
const result = require(`./validators/${field}`)(req.body[field])
if (!result)
return res.status(400).json({ message: 'bad-request', status: 400 })
}
}
The purpose of the following code is to check whether an email already exists in MongoDB, using express-validator:
app.post('/registerPage',[check('email').custom((email) => {
// connect to database
let MongoClient = require('mongodb').MongoClient;
let url = 'mongodb://localhost';
MongoClient.connect(url, function(err, client) {
if (err) throw err;
let db = client.db('Mydatabase');
// search database
return db.collection('users').findOne({
email: email
}).then(user => {
if (user) {
console.log(user); // here console shows correct record in database
return Promise.reject('E-mail already in use');
}
// otherwise, it returns null
});
})
}).withMessage('Error Message Example')], (req, res) => {
// Handle the request
const errors = validationResult(req);
if (!errors.isEmpty()) {
return res.status(422).json({ errors: errors.array() })
}
});
When email already exists, console shows Promise.reject('E-mail already in use');.
The problem is when email does not exist, although it doesn't show Promise.reject, the code cannot process any further, validationResult(req) is not empty, so it still prints out the error message 'Error Message Example'. But there isn't any problem with non-custom validators which can successfully pass the checks.
I tried to add an else statement where !user, it doesn't work.
The question is how to pass the custom validation check, or why the array validationResult(req) is not empty even it should be? How do I make sure validationResult is empty after all checks were passed.
The issue is you are returning the promise in the callback of MongoClient.connect and not the validator function. Try using Promise wrapper like:
app.post('/registerPage',[check('email').custom((email) => {
return new Promise((resolve, reject) => {
// connect to database
let MongoClient = require('mongodb').MongoClient;
let url = 'mongodb://localhost';
MongoClient.connect(url, function(err, client) {
if (err) throw err;
let db = client.db('Mydatabase');
// search database
return db.collection('users').findOne({
email: email
}).then(user => {
if (user) {
console.log(user); // here console shows correct record in database
return reject('E-mail already in use');
}
return resolve();
});
})
});
}).withMessage('Error Message Example')], (req, res) => {
// Handle the request
const errors = validationResult(req);
if (!errors.isEmpty()) {
return res.status(422).json({ errors: errors.array() })
}
});
Hope this helps!
I've been working on an application which allows me to add companies to a database. Originally my code was pure spaghetti, so I wanted to modularize it properly. For this purpose, I added routes, a controller and a dao.
This is how my code looks right now
Routes
app.post('/loadcompanies', (req, res)=> {
companiesController.loadcompany(req.body, (results)=>{
console.log(results);
res.send(200, "working!");
})
})
Controller
module.exports.loadCompany = (body, callback)=>{
companiesDao.loadCompany(body, callback);
}
Dao
module.exports.loadCompany = (company, callback)=>{
MongoClient.connect(conexionString, (err, database) => {
if (err) console.log(err);
db = database;
console.log(company);
db.collection('companies').insert(company, (err, result)=>{
callback({message:"Succesfully loaded company", company:result});
});
})
}
My current concern is that working with errors when modularizing like this is confusing. I tried adding a try-catch method around the db insert and throwing and error if there is one, but that doesn't seem to work. Other things I've tried is returning the error in the callback, like this:
if (err) callback (err, null);
but I end up getting a "Can't set headers after they are sent." error.
How would you handle errors in this situation? For example, in the case that someone tries to add a duplicate entry in an unique element.
You should be able to simply do the error checking inside the callback for the insert function:
db.collection('companies').insert(company, (err, result)=>{
if (err) {
callback(err, null);
return;
}
callback(null, {message:"Succesfully loaded company", company:result});
});
If you get an error like you say, that's probably because the database is actually returning an error. You could also make your errors more specific, like:
module.exports.loadCompany = (company, callback)=>{
MongoClient.connect(conexionString, (err, database) => {
if (err) {
callback(new Error('Connection error: ' + err.Error());
return;
}
db = database;
console.log(company);
db.collection('companies').insert(company, (err, result)=>{
if (err) {
callback(new Error('Insertion error: ' + err.Error());
return;
}
callback(null, {message:"Succesfully loaded company", company:result});
});
})
Here is your loadCompany done in async / await format.
Notise there is no need for error checking, errors will propagate as expected up the promise chain.
Note I've also changed loadCompany to be an async function too, so to call it you can simply do var ret = await loadCompany(conpanyInfo)
module.exports.loadCompany = async (company)=>{
let db = await MongoClient.connect(conexionString);
console.log(company);
let result = await db.collection('companies').insert(company);
return {message:"Succesfully loaded company", company:result};
}
the code is this
module.exports = {
index: function (req, res, next) {
//get an array of all users in user collection
Notification.find(function foundNotification(err, notifications) {
if (err) return next(err);
var elusuario=[];
User.findOne(2, function foundUser (err, user) {
if (err) return next(err);
if (!user) return next();
console.log(user);
console.log("----------------------------");
elusuario = user;
console.log(elusuario);
});
res.view({
notifications: notifications,
elusuario: elusuario
});
})
}
};
That is the controller and in the console prints elusuario good but in the view the user hasn't values. why?
i think is something is something related to the globals variables. but i dont know
thanks
EDIT
all right so the method is async. what im trying to do is find the notifications and the user by her user.id and get the user.name so what if i do this
module.exports = {
index: function (req, res, next) {
//get an array of all users in user collection
Notification.find(function foundNotification(err, notifications) {
if (err) return next(err);
User.find(function foundUser (err, users) {
if (err) return next(err);
var usuarios_locotes = [];
_.each(notifications, function (notification) {
_.each(users, function (user) {
if(notification.token_user==user.token){
console.log(user.token);
usuarios_locotes.push(user);
console.log(usuarios_locotes);
};
});
});
res.view({
notifications: notifications,
users: usuarios_locotes
});
});
})
}
};
it still not working? the __.each is an async funtion to?
sorry for all this maybe stupid questions
The method findOne of User object runs asynchronously. Because of this, you are rendering the view before the findOne returns the user object.
If you put a console.log before the render.view, it'll print the output before the console.log inner findOne method.
When the code is running, the function foundNotification is not executed before you call the res.view. My advice for you is read about Promises.
You can change your code as below to work:
function (req, res, next) {
//get an array of all users in user collection
Notification.find(function foundNotification(err, notifications) {
if (err) return next(err);
var elusuario=[];
User.findOne(2, function foundUser (err, user) {
if (err) return next(err);
if (!user) return next();
console.log(user);
console.log("----------------------------");
elusuario = user;
console.log(elusuario);
res.view({
notifications: notifications,
elusuario: elusuario
});
});
});
}
the findOne Method is an asynchrone method,so it's executed without provinding the res.view with the appropriate data
try to wrap the whole logic in the same function, it may look ugly but it ll do the thing for now
All right so.. first really thanks to everybody. I solve this shit.
I know this is not the right way to do this but it works, so for my proposes it's fine.
the problem after the EDIT was that in the view I'm trying to write an object with parameters but what I've was sending was vector of vector so changing this line:
usuarios_locotes.push(new Object(users[h]));
I can send a vector of objects.
So.. anyway thanks cause later i will change my code to do it better and efficient
This was my first post so sorry for not read the first steps of how to use this haha cause i think i have been make a lot of mistakes.
And sorry for my English :C
Hello guys am new to Sails.js ( using MySQL )
Am trying to find if a user already exists before registration.
Here this is the code:
register:function(req, res, next){
var params = req.params.all();
User.find({
or : [
{ usrnm:params.usrname },
{ eml:params.eml }
]
})
.exec(function (err, user){
if (err) {
return res.negotiate(err);
}
if (user) {
res.status(400);
return res.json('User already exists!');
}
});
User.create(params, function(err, user){
if(err){
return next(err);
}
res.status(201);
res.json(user);
});
}
The problem is:
The response is always "User already exists!" with status code - 400
If user exists with the given username or/and email, the above message is displayed regardless and then something is getting logged in the console ( which I dont understand ) and user is not created as in my MySQL those two fields are unique.
**If user does not exists ** the user gets created behind but it still displays the above message.
I want to display the message only if user exists (ie if given credentials matches) else respond with 201
register:function(req, res, next){
var params = req.params.all();
User.find({
or : [
{ usrnm:params.usrname },
{ eml:params.eml }
]
})
.exec(function (err, users){
if (err) {
return res.negotiate(err);
}
if (users.length) {
res.status(400);
return res.json('User already exists!');
} else {
User.create(params, function(err, user){
if(err){
return next(err);
} else {
res.status(201);
res.json(user);
}
});
}
});
}
You should call the create user method if a user with those parameters do not already exist, and so should put it inside the callback.
The User.find() function returns an array, so you need to check its length to see if there are any matching objects.
Okay guys I figured out a solution, i will put it here in case if it helps someone
if (user) { // will be true even if user = []
res.status(400);
return res.json('User already exists!');
}
In case when user is not found in the DB , user is = [ ] , this means [ ] != false
, hence the message within the scope is getting displayed.