So a simple explanation of what I am doing. First, I am accepting a GET request from an end user. Second, I am passing a (I am making a GET request now) parameter from the get request to an async function that returns a user's email address based on the parameter (essentially a vanity url. "Bob" vs "Robert Richardson").
Third, I am making on more GET request, to a second system, which returns a JSON file containing different tidbits about the user.
I know the callouts work normally because I can run node index.js with a function where I manually pass in the information I need, and it returns the desired results. But when I start my nodejs server, and try to respond to an incoming GET request (me testing, definitely not live) I get very weird results...
Here is simply what I am trying to get working at the moment:
//server.js
const express = require('express');
const bodyParser = require('body-parser');
const app = express();
const port = 8000;
app.use(bodyParser.urlencoded({
extended: true
}));
require('./app/routes')(app, {});
app.listen(port, () => {
console.log('test is listening on port :: ' + port);
});
//routes.js
const getdata = require('./getData '); //contains function for GET request one to convert param to email
async function getReturn(app, db) {
app.get('/getDataFrom/:alias', (req, res) => {
const alias = req.params.alias;
console.log('alias : ' + alias);
getEmailFromPromise(alias);
});
}
async function getEmailFromPromise(alias) {
console.log('getting email');
let output = await getEmail(alias);
console.log('output :: ' + output);
// return output;
}
function getEmail() {
return new Promise(resolve => {
let email = getdata.getUserInfo(alias);
resolve(email);
}, 1000);
}
Worth noting, JS and Node are not what I commonly code it, but I need to for a project I am helping out with. I can get simple examples to work, but not my one making requests.
Passing in GET: localhost:8000/getDataFrom/bob
The above returns the following:
test is listening on port :: 8000
alias : rrichardson
getting email
output :: undefined //I am wanting this to log after I actually get the email
email found :: robert.richardson#company.com //I do get this back, but out of order. The undefined above should also be this
The other file if it helps (it is exported properly):
//this is callout one getData
async function getUserInfo(alias){
client.connect();
client.query('select email, firstname, lastname from salesforce.user WHERE
alias = \''+ alias + '\'', (err, res) => {
if (err) console.log('err :: ' + err);
// console.log(res.rows);
client.end();
var email = res.rows[0].email;
if(email != null){
console.log('email found :: ' + email);
return email;
}
else return 'No Email Found';
});
}
Obviously I left out my credentials, but the last js file DOES work just fine when I pass specific data into it. Again, just issues when trying to respond to a GET request that is incoming to me. I would really appreciate any help clearing this up. I am pretty sure I can get the second GET request figured out if I can get some help figuring out this first one.
Thanks!
You need getReturn to return the promise generated by the getEmailFromPromise call. Because app.get uses a callback rather than a promise, you'll have to explicitly convert it to a promise first - in which case there's not much use in making getReturn async.
function getReturn(app, db) {
return new Promise((resolve) => {
app.get('/getDataFrom/:alias', (req, res) => {
const alias = req.params.alias;
console.log('alias : ' + alias);
getEmailFromPromise(alias)
.then(resolve);
});
});
}
The other problem is that getUserInfo also uses callbacks rather than promises - you can't just turn it into an async function, you'll have to explicitly convert it to return a Promise as well:
function getUserInfo(alias){
return new Promise((resolve, reject) => {
client.connect();
client.query('select email, firstname, lastname from salesforce.user WHERE
alias = \''+ alias + '\'', (err, res) => {
if (err) {
console.log('err :: ' + err);
reject(err);
}
// console.log(res.rows);
client.end();
var email = res.rows[0].email;
if(email != null){
console.log('email found :: ' + email);
resolve(email);
}
else resolve('No Email Found');
});
});
}
You also need to use await to consume promises if you want the line below to run only after the promise has resolved:
function getEmail() {
return new Promise(resolve => {
let email = await getdata.getUserInfo(alias);
But it doesn't make much sense to await something that's a promise if you're just going to resolve it immediately. (and the second argument you provide to the promise in getEmail, 1000, doesn't make any sense)
Just return the promise itself:
function getEmail() {
return getdata.getUserInfo(alias);
}
you are mixing async and promises, it would be avoid.
Your problem is th function getUserInfo is async but it has no "await" part, it is not waiting for "resolve" or return so it returns nothing or "undefined" because you ra anssigning that to the email in " let email = getdata.getUserInfo(alias);" you could use primse in this step, some like this:
function getUserInfo(alias){
return new Promise(function(resolve, reject){
client.connect();
client.query('select email, firstname, lastname from salesforce.user WHERE alias = \''+
alias + '\'', (err, res) => {
if (err) reject('err :: ' + err);
// console.log(res.rows);
client.end();
var email = res.rows[0].email;
if(email != null){
console.log('email found :: ' + email);
resolve(email);
}
else reject('No Email Found');
});
}
}
and call it:
function getEmail() {
return new Promise(resolve => {
getdata.getUserInfo(alias).then(function(email){
resolve(email);
});
});
}
Related
I'm new to JavaScript and cannot seem to make this work , the topic of quiz depends on the user input... when the user presses next , I get the topic (this also takes user to the main quiz page), then i have to fetch data from the api with the topic as a parameter... I have to process the result of the fetch operation.. Then I have to pass that info to to the main quiz page... but the variable that is supposed to be populated by the fetch request is still undefined when i pass is to the main quiz page
var Allquestions;
var sheetdb = require('sheetdb-node');
// create a config file
var config = {
address: 'https://sheetdb.io/api/v1/9djmf8ydc7hwy',
};
//sheetdb
// Create new client
var client = sheetdb(config);
function downloadquestions(topic) {
console.log(topic);
client.read({ limit: 2, sheet: topic }).then(function(data) {
console.log(data + " in client.read func")
processQuestions(data);
}, function(err){
console.log(err);
});
}
async function processQuestions(data) {
console.log(data + "data in process");
Allquestions = JSON.parse(data);
console.log(Allquestions[0].Question + " This is defined");
}
app.get("/", (req, res) => {
res.render("pages/index", { title: "Home"});
});
// app.post("/" , urlencodedParser ,(req , res) => {
// console.log(req.body.topic);
// })
app.get("/questions", urlencodedParser , (req , res) => {
downloadquestions(req.body.topic);
console.log(Allquestions + " this is undefined");
res.render("/pages/quizpage" , {Allquestions})
})
There are a few issues with your code, you have a broken promise chain, client.read( is a promise, and that promise is going nowhere. You either return it, or await it. To be able to await your will need to also mark your route (req, res) as async too.
Your code is a little mixed up, you have Allquestions as a global var, this isn't great for multi-user, as the last topic is going to override this each time.
Also try and avoid swallowing exceptions in utility functions, try and keep your exception handling at the top level, eg. in your case inside your req/res handler.
So with all this in mind, your refactored code could look something like ->
const sheetdb = require('sheetdb-node');
// create a config file
const config = {
address: 'https://sheetdb.io/api/v1/9djmf8ydc7hwy',
};
//sheetdb
// Create new client
const client = sheetdb(config);
async function downloadquestions(topic) {
const data = await client.read({ limit: 2, sheet: topic });
return processQuestions(data);
}
function processQuestions(data) {
return JSON.parse(data);
}
app.get("/", (req, res) => {
res.render("pages/index", { title: "Home"});
});
app.get("/questions", urlencodedParser , async (req , res) => {
try {
const allQuestions = await downloadquestions(req.body.topic);
res.render("/pages/quizpage" , {Allquestions});
} catch (e) {
console.error(e);
res.end('There was an error');
}
})
I have a function running on the creation of a document.
When I send this information to an external API Firebase returns on 'ok' message before the API call is complete.
const functions = require('firebase-functions');
const request = require('request');
const admin = require('firebase-admin');
const rp = require('request-promise');
const port = '****';
const ip = '***.***.***.***';
admin.initializeApp(functions.config().firebase);
exports.sendUser = functions.firestore
.document('user/{userId}')
.onCreate((snap, context) => {
const data = snap.data();
const options = {
method: 'POST',
uri: 'http://' + ip + ':' + port + '/user',
body: data,
json: true,
};
rp(options)
.then(function (parsedBody) {
console.log('TEN ', parsedBody);
return parsedBody;
})
.catch(function (err) {
console.log('ERR ', err);
return err;
});
});
As you can see from my function it is not doing anything special apart from sending the data to an external source.
The API look like the following:-
app.post('/user', function (req, res) {
fs.exists(path, function(exists) {
if (exists === true) {
console.log('Currently Printing Different User Info');
fs.unlinkSync(path);
res.status(404).json({errorCode: 404, errorMessage: 'Currently Printing Different User.'});
return;
} else {
fs.writeFile(path, '', () => { console.log('File Created'); });
fs.unlinkSync(path);
res.status(200).json({statusCode: 200, statusMessage: 'Here we go'});
return;
}
});
})
How can I get Firebase to recognise the returned 404 as a failed call, and also wait until the call is complete before returning ok or failed.
The API is behaving correctly with Postman but not when data is posted via Firebase.
Has anyone encountered this before, or can anybody see what I am doing wrong?
The data is being parse over to the serve but only once Firebase has returned with 'ok' even if I purposely trigger a fail.
I need this in place to be able to use the Firebase Cloud Function retry function.
Images can be seen # https://imgur.com/a/1qYxrci
The Cloud Function returns the result before the call is complete because you don't return the Promise returned by the request-promise call.
Changing your code as follows should do the trick (at least for this problem):
exports.sendUser = functions.firestore
.document('user/{userId}')
.onCreate((snap, context) => {
const data = snap.data();
const options = {
method: 'POST',
uri: 'http://' + ip + ':' + port + '/user',
body: data,
json: true,
};
return rp(options) // <-- See the change here
.then(function (parsedBody) {
console.log('TEN ', parsedBody);
return parsedBody;
})
.catch(function (err) {
console.log('ERR ', err);
return err;
});
});
I would suggest you watch the official Video Series (https://firebase.google.com/docs/functions/video-series/) which explain very well this point about returning Promises for background functions (in particular the ones titled "Learn JavaScript Promises").
I am attempting to send a text message when a user requests to reset their password. I would like to wait for the message to be sent to alert the user if it was successful or not. I am currently attempting to do it as follows:
async function sendResetPasswordTextMessage(req, res) {
let result = {};
let phoneNumber = req.body.phoneNumber;
if (phoneNumber === undefined) {
return sendInvalidParametersMessage(res);
}
phoneNumber = phoneNumber.toString();
const userProfile = await models.UserProfile.findOne({
where: {
phoneNumber: phoneNumber
}
});
************************** RELEVANT CODE TO ISSUE *************************
if (userProfile) {
const message = "Your username is:\n" + userProfile.username;
const sent = await AWSSNSClient.sendMessage(message, phoneNumber);
if (!sent) {
result.error = setTitleAndMessage("Error", "An error occurred");
} else {
result.success = setTitleAndMessage("Success", "Message sent");
}
}
return res.send(result);
***************************************************************************
}
In my other class AWSSNSClient, I have the following sendMessage function:
function sendMessage(message, phoneNumber) {
const params = {
Message: message,
MessageStructure: "string",
PhoneNumber: "+1" + phoneNumber
};
let sent = false;
sns.publish(params, function(err, data) {
if (err) {
console.log(err, err.stack); // an error occurred
}
else {
sent = true;
}
});
return sent;
}
I cannot figure out how to make sendMessage wait for sns.publish to return before it returns itself. I have tried making it an async method and adding await on sns.publish, but the function still returns before sent gets set to true.
I know that the messages are sending without error because I am receiving them and no console logs are printed.
Stumbled on this one via Google trying to figure this out myself today - short answer that I am now using:
You can now do this with Async/Await — and Call the AWS service (SNS for example) with a .promise() extension to tell aws-sdk to use the promise-ified version of that service function (SNS) instead of the call back based version.
The only caveat here is the containing function must ALSO be async to utilize the await syntax.
For example:
let snsResult = await sns.publish({
Message: snsPayload,
MessageStructure: 'json',
TargetArn: endPointArn
}, async function (err, data) {
if (err) {
console.log("SNS Push Failed:");
console.log(err.stack);
return;
}
console.log('SNS push suceeded: ' + data);
return data;
}).promise();
The important part is the .promise() on the end there. Full docs on using aws-sdk in an async / promise based manner can be found here: https://docs.aws.amazon.com/sdk-for-javascript/v2/developer-guide/using-promises.html
In order to run another aws-sdk task you would similarly add await and the .promise() extension to that function (assuming that is available).
For anyone who runs into this thread and is actually looking to simply push multiple aws-sdk promises to an array and wait for that WHOLE array to finish (without regard to which promise executes first) I ended up with something like this:
let snsPromises = [] // declare array to hold promises
let snsResult = await sns.publish({
Message: snsPayload,
MessageStructure: 'json',
TargetArn: endPointArn
}, async function (err, data) {
if (err) {
console.log("Search Push Failed:");
console.log(err.stack);
return;
}
console.log('Search push suceeded: ' + data);
return data;
}).promise();
snsPromises.push(snsResult)
await Promise.all(snsPromises)
Hope that helps someone that randomly stumbles on this via google like I did!
stackdave will that actually wait?
Necevil "Search push suceeded will get logged twice" because you're mixing calling operations by passing a callback and using promises. You should only use one method of getting the result
let snsResult = await sns.publish({
Message: snsPayload,
MessageStructure: 'json',
TargetArn: endPointArn}).promise()
will do the trick
You can simply use callbacks for that. Modify your sendMessge like this
function sendMessage(message, phoneNumber, cb) {
const params = {
Message: message,
MessageStructure: "string",
PhoneNumber: "+1" + phoneNumber
};
sns.publish(params, cb);
}
then on your main file you can supply callback like this
if (userProfile) {
const message = "Your username is:\n" + userProfile.username;
AWSSNSClient.sendMessage(message, phoneNumber, (err, data) => {
if (err) {
result.error = setTitleAndMessage("Error", "An error occurred");
}
else {
result.success = setTitleAndMessage("Success", "Message sent");
}
res.send(result);
});
}
Here the right updated API, August 2018, Necevil answer send the sms twice.
// using config.env
AWS.config.region = 'eu-west-1';
AWS.config.update({
accessKeyId: process.env.AMAZON_SMS_ID,
secretAccessKey: process.env.AMAZON_SMS_TOKEN,
});
// parameters
let params = {
Message: contentSMS, // here your sms
PhoneNumber: mobile, // here the cellphone
};
const snsResult = await sns.publish(params, async (err, data) => {
if (err) {
console.log("ERROR", err.stack);
}
console.log('SNS ok: ' , JSON.stringify (data));
});
If you're having issues with duplicate SNS messages being sent, I fixed this issue by utilizing examples from AWS:
// Load the AWS SDK for Node.js
var AWS = require('aws-sdk');
// Set region
AWS.config.update({region: 'REGION'});
// Create publish parameters
var params = {
Message: 'MESSAGE_TEXT', /* required */
TopicArn: 'TOPIC_ARN'
};
// Create promise and SNS service object
var publishTextPromise = new AWS.SNS({apiVersion: '2010-03-31'}).publish(params).promise();
// Handle promise's fulfilled/rejected states
publishTextPromise.then(
function(data) {
console.log("Message ${params.Message} send sent to the topic ${params.TopicArn}");
console.log("MessageID is " + data.MessageId);
}).catch(
function(err) {
console.error(err, err.stack);
});
By utilizing a traditional .then() I was able to squash the duplicate message bug mentioned in comments above.
You can create a async function what use the promise method
async function sendMessage(message, phoneNumber){
const params = {
Message: message,
PhoneNumber: phoneNumber
};
return new Promise((resolve, reject) => {
SNS.publish(params, (err, data) => {
if (err) {
console.log("Search Push Failed:");
console.log(err.stack);
return reject(err);
} else {
console.log('Search push suceeded:' + phoneNumber);
return resolve(data);
}
})
});
}
and then you can call
var s= await sendMessage(message,phoneNumber);
I am a beginner and am currently making a User Management system in NodeJS, I had previously done it with MongoDB, Express. Right now im making it all again with Express, Sequelize and Postgresql to better understand some concepts.
What im stuck at is the reset page where I previously used Async.waterfall to get the email id and send email using SendGrid, but now I want to know how can I convert it using Promises..? It is a bit confusing to understand how to use them with concurrent callbacks.
Here is the previous code using the async.waterfall :
app.post('/forgotpassword', function(req, res, next) {
async.waterfall([
function(done) {
crypto.randomBytes(20, function(err, buf) {
var token = buf.toString('hex');
done(err, token);
});
},
//2
function(token, done) {
User.findOne({ 'local.email': req.body.email }, function(err, user) {
if (!user) {
req.flash('forgotMessage', 'No account with that email address exists.');
return res.redirect('/forgotpassword');
}
user.local.resetPasswordToken = token;
user.local.resetPasswordExpires = Date.now() + 3600000; // 1 hour
user.save(function(err) {
done(err, token, user);
});
});
},
//3
function(token, user, done) {
var nodemailer = require('nodemailer');
var sgTransport = require('nodemailer-sendgrid-transport');
var options = {
auth: {
api_key: ''
}
};
var mailer= nodemailer.createTransport(sgTransport(options));
var mailOptions = {
to: user.local.email,
from: 'passwordreset#demo.com',
subject: 'Node.js Password Reset',
text: 'You are receiving this because you (or someone else) have requested the reset of the password for your account.\n\n' +
'Please click on the following link, or paste this into your browser to complete the process:\n\n' +
'http://' + req.headers.host + '/reset/' + token + '\n\n' +
'If you did not request this, please ignore this email and your password will remain unchanged.\n'
};
mailer.sendMail(mailOptions, function(err) {
req.flash('forgotMessage', 'An e-mail has been sent to ' + user.local.email + ' with further instructions.');
done(err, 'done');
});
}
],
//2 out of Async
function(err) {
if (err) return next(err);
res.redirect('/forgotpassword');
});
});
From async.waterfall documentation
Runs an array of functions in series, each passing their results to
the next in the array. However, if any of the functions pass an error
to the callback, the next function is not executed and the main
callback is immediately called with the error.
So its exactly the same job as Promise.then do, just chain your promises.
crypto.randomBytes(20)
.then( function (buf) {
var token = buf.toString('hex');
return token;
})
.then( function(token) {
return Model.User.findOne({where: {'email' : req.body.email}});
})
.then(function (user) {
if(!user){
// throw no user found error
}
return Model.User.create();
})
.catch( function(err) {
// error handling
// catch no user found error and show flash message
});
You have to have single catch in the end of promises chain, and then should not to be inside of another .then function. I can suggest to read this article - We have a problem with promises.
I am trying to write a function that add or edit some fields on a User object.
The problem come when I try to save the user, if I use user.save, the Promise is rejected with error 206 UserCannotBeAlteredWithoutSessionError.
However, if I get the session id (and documentation about that is scarce), the promise never get resolve, nor rejected. The app seems to just jump to the callback.
My function:
function update(user, callback) {
let query = new Parse.Query(Parse.User);
query.equalTo("username", user.email);
query.find().then(
(users) => {
if(users.length === 0) {
callback('Non existent user');
} else {
let user = users[0];
// user.set('some', 'thing');
console.log('save');
user.save(/*{
sessionToken: user.getSessionToken()
}*/).then(
(test) => {
console.log('OK - ' + test);
callback();
}, (err) => {
console.log('ERR- ' + require('util').inspect(err));
// console.log(callback.toString());
callback(error.message);
}
);
}
},
(error) => {
callback(error.message);
}
);
}
Called with:
var async = require('async'),
baas = require('./baas.js');
async.waterfall([
(callback) => {
callback(null, {
email: 'user#test.com',
password: 'password'
});
},
(user, callback) => {
console.log('connect');
baas.connect(() => { //Initialize the connection to Parse, and declare use of masterKey
callback(null, user);
});
},
(user, callback) => {
console.log('update');
baas.update(user, (err) => {
callback(err);
});
}
], (err) => {
console.log('Error: ' + err);
});
The logs become:
Without session token:
connect
update
save
ERR- ParseError { code: 206, message: 'cannot modify user sA20iPbC1i' }
With session token:
connect
update
save
I do not understand how it is possible that the promise just callback without printing anything, nor why no error are raised anywhere.
Edit:
Following #user866762 advice, I tried to replace the query with Parse.User.logIn and use the resulting User object.
While this solution give me a sessionToken, the end result is the same, parse crash if I don t provide the session token, or give me a error if I do.
According to the Parse Dev guide:
...you are not able to invoke any of the save or delete methods unless the Parse.User was obtained using an authenticated method, like logIn or signUp.
You might also try becoming the user before saving, but I have my doubts that will work.
When you're "get[ting] the session id" my guess is that you're really breaking something. Either Parse is having a heart attack at you asking for the session token, or when you're passing it in save you're causing something there to explode.