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unable to catch any form of error or response from firebase notification callback function in Node js

I am using the package "fcm-node" in order to send notifications to certain device id.
the sendNotification function is as follows:
const FCM = require('fcm-node');
const serverKey = process.env.SERVER_KEY;
const fcm = new FCM(serverKey);
function sendNotification(registrationToken, title, body, type, key) {
const message = {
to: registrationToken,
collapse_key: key,
notification: {
title: title,
body: body,
delivery_receipt_requested: true,
sound: `ping.aiff`
},
data: {
type: type,
my_key: key,
}
};
fcm.send(message, function (err, value) {
if (err) {
console.log(err);
return false;
} else {
console.log(value);
return value;
}
});
};
module.exports = {
sendNotification
};
The api function I use to call this function is as follows:
router.get('/test', async (req, res, next) => {
const promise = new Promise((resolve, reject) => {
let data = sendNotification('', 'dfsa', 'asds', 'dfas', 'afsdf');
console.log(data)
if (data == false) reject(data);
else resolve(data);
});
promise
.then((data) => { return res.status(200).send(data); })
.catch((data) => { return res.status(500).send(data) })
});
When I console.log the "err" and "value" from the sendNotification, I get either of the followings:
{"multicast_id":4488027446433525506,"success":1,"failure":0,"canonical_ids":0,"results":[{"message_id":"0:1652082785265643%557c6f39557c6f39"}]};
{"multicast_id":8241007545302148303,"success":0,"failure":1,"canonical_ids":0,"results":[{"error":"InvalidRegistration"}]}
In case it is successful, I made sure that the device is receiving the notification.
The problem is in the api's data. It is always "undefined" and weither send notification is successful or not I get the 200 Ok status.
What seems to be the problem?

You can't return anything from the function (err, value) {} callback of a node-style asynchrnous function.
Your sendNotification() function needs to return a promise. util.promisify() makes the conversion from a node-style asynchronous function to a promise-returning asynchronous function convenient. Note the return, it's important:
const FCM = require('fcm-node');
const serverKey = process.env.SERVER_KEY;
const fcm = new FCM(serverKey);
const { promisify } = require('util');
fcm.sendAsync = promisify(fcm.send);
function sendNotification(registrationToken, title, body, type, key) {
return fcm.sendAsync({
to: registrationToken,
collapse_key: key,
notification: {
title: title,
body: body,
delivery_receipt_requested: true,
sound: `ping.aiff`
},
data: {
type: type,
my_key: key,
}
});
}
module.exports = {
sendNotification
};
Now you can do what you had in mind
router.get('/test', async (req, res, next) => {
try {
const data = await sendNotification('', 'dfsa', 'asds', 'dfas', 'afsdf');
return res.status(200).send(data);
} catch (err) {
return res.status(500).send(err);
}
});

Maybe it will help, at first try to return your response (the promise) in sendNotification, as actually you have a void function, that's why it's always undefined and after in your route
router.get('/test', async (req, res, next) => {
try {
const data = sendNotification('', 'dfsa', 'asds', 'dfas', 'afsdf');
if (data) {
return res.status(200).send(data);
}
} catch(err) {
return res.status(500).send(err);
}
});

hash field with promiss function in nodejs from utilite

i have a class for hash data in nodejs .
this is my class :
const bycrypt = require("bcrypt");
module.exports = new (class Utilitie {
HashField(field) {
return new Promise((resolve, reject) => {
bycrypt.hash(field, bycrypt.genSaltSync(15), (error, hash) => {
if (error) return reject(error);
resolve(hash);
});
});
}
})();
and this is my controller for use this class for hash data :
async ResetPassword(req, res, next) {
const result = await this.ValidationAction(req, res);
if (result[0]) {
let user = await User.findOne({ userName: req.body.userName }).then(
(user) => {
if (!user) return this.Notfound(res);
user.password = Utilite.HashField(req.body.password).then(
(error, hash) => {
console.log("in controller", hash);
}
);
user.save();
}
);
this.Ok(res);
}
return this.BadRerquest(res, result[1]);
}
but it not hash field and it return the undefined .
whats the problem ? how can i solve this problem ????

The argument that your then callback receives will be the hash value. The return value of the then() call will be another promise. You meant to use await:
async ResetPassword(req, res, next) {
const result = await this.ValidationAction(req, res);
if (result[0]) {
const user = await User.findOne({ userName: req.body.userName });
if (!user) return this.Notfound(res);
user.password = await Utilite.HashField(req.body.password);
// ^^^^^
await user.save();
this.Ok(res);
} else {
this.BadRerquest(res, result[1]);
}
}

Getting result from MySQL

My backend is consist of Api and DB. When I want to get response from DB I have had delayed output by 1 query.
API (I think api is ok. Start read DB first)
app.post('/api/query', (req, res) => {
console.log(`\n Query input : ${JSON.stringify(req.body)}`);
let queryInput = (Object.values(req.body).join(' '));
if(!dbApi.checkArray(queryInput)){ //If array is not made from clear strings
res.json(dbApi.queryFromUser(queryInput));
}
else{
res.json(dbApi.queryOutput);
}
});
app.listen(dbConfig.server.port, () =>
console.log(`Server running on port ${dbConfig.server.port}`));
DB
queryOutput = [];
const receivingQuery =(queryInput) => {
db.query(queryInput, (err, result) =>{
if(err) throw err+' : '+queryInput;
queryOutput = result;
console.log("\nQuery output "+ JSON.stringify(queryOutput)); //Output (result) is ok
});
return queryOutput //Here is Output from previous query (sends to API)
}
module.exports = {
queryOutput: queryOutput,
queryFromUser: receivingQuery,
}
I tryied callback method and I rewrite it couple of times. But I dont have enough skill to solve it.

If You want to return result of query so simply do following things:
add query method to db module:
function query(sql, args = []) {
return new Promise(function(resolve, reject) {
db.query(sql, args, (err, result) => {
if (err) return reject(err);
resolve(result);
});
});
}
// extra feature, getting user by id
async function getUserById(id) {
const result = await query('SELECT * FROM users WHER id = ? LIMIT 1', [id]);
if (Array.isArray(result) && result[0]) return result[0];
return null;
}
module.exports = {
query,
getUserById, // export user by id
queryOutput,
queryFromUser: receivingQuery,
}
use it (with async and await):
app.post('/api/query', async (req, res) => {
try {
console.log('Query input:', req.body);
const queryInput = Object.values(req.body).join(' ');
const result = await dbApi.query(queryInput);
res.json(result);
}
catch (error) {
console.error(error);
res.status(500).json({message: 'Please try again soon'});
}
});
app.get('/api/users/:id', async (req, res) => {
try {
const user = await dbApi.getUserById(req.params.id);
if (!user) return res.status(404).json({message: 'User not found'});
res.status(200).json(user);
}
catch (error) {
console.error(error);
res.status(500).json({message: 'Please try again soon'});
}
});
app.listen(dbConfig.server.port, () =>
console.log('Server running on port', dbConfig.server.port));

How to execute bcrypt.compare inside Sequelize .then?

I'm trying to build a login page where I get the hashed password from mysql db using Sequelize and then calling bcrypt compare to dehash the password and compare it with the user's login input for authentication.
However, bcrypt compare is always executing slower than the return causing the value to always be "". I know this has to do with asynchronous behaviour but I don't know how to properly write this code to make it work.
authenticate: (req, res) => {
let userDetails = req.query;
User.findOne({
where: {
username: userDetails.username
}
})
.then((user) => {
// How can I make this so, correctPassword() finishes
// and then the authenticated variable will be either false or true?
let authenticated = correctPassword(userDetails.password, user.password);
return authenticated;
})
.then((authenticated) => {
// right now authenticated is "" in client side console.
res.send(authenticated);
})
.catch((error) => {
console.log('there was an error: ', error);
});
}
}
const correctPassword = (enteredPassword, originalPassword) => {
return bcrypt.compare(enteredPassword, originalPassword, (err, res) =>{
return res;
});
}

You're almost there. You correctly intuited that correctPassword executes asyncronously, though it is written as if it's syncronous.
First off, let's make correctPassword a promise, so we can use async/await or call .then on it
const correctPassword = (enteredPassword, originalPassword) => {
return new Promise(resolve => {
bcrypt.compare(enteredPassword, originalPassword, (err, res) =>{
resolve(res)
});
})
}
Next, you have two approaches to ensure the order of operations in your code executes correctly:
(Recommended) Use async/await syntax allowing us to write synchronous-looking code:
authenticate: async (req, res) => {
let userDetails = req.query;
try {
const user = await User.findOne({
where: {
username: userDetails.username
}
});
const authenticated = await correctPassword(userDetails.password, user.password);
res.send(authenticated);
} catch(e) {
res.status(400).send(e)
}
}
Continue using promises:
authenticate: (req, res) => {
let userDetails = req.query;
User.findOne({
where: {
username: userDetails.username
}
}).then(() => {
correctPassword(userDetails.password, user.password)
.then(authenticated => {
res.send(authenticated)
})
.catch(e => {
res.send(e)
})
})
}

You can't assign async function to variable which is used by sync code later on. If you want to do sync function, you can use await/aync. But in here I recommend you use promise for compare function as well.
User.findOne({
where: {
username: userDetails.username
}
})
.then((user) => {
return correctPassword(userDetails.password, user.password);
})
.then((authenticated) => {
res.send(authenticated);
})
Bcrypt also supports promise.
const correctPassword = (enteredPassword, originalPassword) => {
return bcrypt.compare(enteredPassword, originalPassword).then((res) =>{
return res;
});
}

Node JS Callback function return nothing

I'm a newbie in node js Development. I just learn node js in short time ago. Here I create a router file
import express from 'express';
import storyController from '../../controllers/story';
const router = express.Router();
router.post('/', (req, res) => {
const { author, title } = req.body;
console.log(author);
const story = {
author: req.body.author,
title: req.body.title,
content: req.body.content,
tags: req.body.tags
};
storyController.createStory(story, function(error, result){
console.log("halo");
if(error)
res.status(500).send({ success: false, message: error.message});
res.status(200).send({ success: true, message: "Success"});
});
});
Then, i create one more file referred as the controller here
import mongoose from 'mongoose';
const Story = mongoose.model('Story');
exports.createStory = async (story) => {
const { author, title } = story;
if(!author){
console.log("hahaAuthor");
return {
error: true,
message: 'You must write an author name!'
};
}
if(!title) {
console.log("haha");
return {
error: true,
message: 'You must write a title!'
}
}
const newStory = new Story({
author: author,
title: title,
content: story.content,
tags: story.tags,
slug: ''
});
newStory.save().then((story) => {
return { error: false, result: story};
}).catch((error) => {
return { error: error};
})
};
But, unfortunately I don't know why my function in router file doesn't call the callback function. The console.log doesn't even called yet. Please help. Otherwise, maybe you have a better way to do this. Thanks!

As createStory is an async function. Change your code like this. You are mixing async with Promise and callback
exports.createStory = async (story) => {
...
// Change the promise to await
let story = await newStory.save();
return { error: false, result: story};
};
Error should be handled in the controller with Promise catch clause.
Something like
router.post('/', (req, res) => {
storyController.createStory.then(data => {
return res.json({error: false, data: data});
}).catch(e => {
return res.json({error: true});
})
});
Note: Either use callback or async. async is the best option now adays

May be this can work:
// 1. callback style
newStory.save().then((story) => {
return cb(null, story);
}).catch((error) => {
return cb(error);
})
// 2. await
await newStory.save();
// controller
router.post('/', (req, res) => {
storyController.createStory.then(data => {
return res.json(...);
}).catch(e => {
return res.json(...);
});
If you use callback style, Error-First Callback is better.