Why is this callback function not executing? - javascript

I have been having this issue. It seems like it works for a while and then breaks without much rhyme or reason to it.
router.get('/home/', function(req, res, next) {
var code = req.query.code;
console.log("acquired code from SC");
req.SC.authorize(code, function(err, accessToken) {
if ( err ) {
throw err;
} else {
console.log("traded code for access token");
req.session.oauth_token = accessToken;
// Client is now authorized and able to make API calls
//res.render('home', { token: accessToken });
soundcloud.getLoggedInUser(accessToken, function(user){
console.log("done getting user from SC");
});
}
});
});
Here is the getLoggedInUser function.
//get data for the user who is logged in
function getLoggedInUser(accessToken, done){
var href = 'https://api.soundcloud.com/me?oauth_token=' + accessToken;
getRequest(href, done);
}
//used for get requests to soundcloud API
function getRequest(href, done){
console.log(href);
requestify.get(href).then(function(response){
console.log(done);
done(response.getBody());
});
}
Here is the output.
acquired code from SC
traded code for access token
https://api.soundcloud.com/me?oauth_token=
[Function]
I'm guessing this is a problem with my node / express setup rather than a problem with this code itself. Any ideas?

Related

How to have express handle and capture my errors

var database = require('database');
var express = require('express');
var app = express();
var cors = require('cors');
app.use(cors());
var bodyParser = require('body-parser');
var urlencodedParser = bodyParser.urlencoded({
extended: false
});
app.post('/dosomething', urlencodedParser, function(req, res) {
if (!req.body.a) {
res.status(500).send(JSON.stringify({
error: 'a not defined'
}));
return;
}
firstAsyncFunction(req.body.a, function(err, result) {
if (err) {
res.status(500).send('firstAsyncFunction was NOT a success!');
} else {
if (result.b) {
secondAsyncFunction(result.b, function(err, data) {
if (err) {
res.status(500).send('secondAsyncFunction was NOT a success!');
return;
}
res.send('EVERYTHING WAS A SUCCESS! ' + data);
});
}
else {
res.status(500).send('result.b is not defined');
}
}
});
});
function firstAsyncFunction(param, callback) {
//Some network call:
// Return either return (callback(null,'success')); or return (callback('error'));
var query = database.createQuery(someOptionsHere);
database.runDatabaseQuery(query, function(err, entities, info) {
if (err) {
return (callback('error'));
}
return (callback(null, 'success'));
});
};
function secondAsyncFunction(param, callback) {
//Some network call:
// Return either return (callback(null,'success')); or return (callback('error'));
var query = database.createQuery(someOptionsHere);
database.runDatabaseQuery(query, function(err, entities, info) {
if (err) {
return (callback('error'));
}
return (callback(null, 'success'));
});
};
var server = app.listen(process.env.PORT || 3000, function() {
var host = server.address().address;
var port = server.address().port;
console.log('App listening at http://%s:%s', host, port);
});
module.exports = app;
I have here a basic express http server. This server has one route, dosomething, which makes two network calls and tells the user if they were a success or not.
This is my entire webserver (this is a bare bones server of my actual server for example purposes). I am now concerned with this server crashing. Reading the docs for express I see there is a default error handler which will catch errors and prevent the server from crashing (http://expressjs.com/en/guide/error-handling.html). I have added the code:
function defaultErrorHandler(err, req, res, next) {
if (res.headersSent) {
return next(err);
}
res.status(500);
res.render('error', { error: err });
}
app.use(defaultErrorHandler);
This still crashes my server though. For example. I had a problem with my database returning an improper JSON response and inside of my firstAsyncFunction (not shown in the code) I tried to parse the JSON and it caused an error telling me it was improper JSON and the server crashed and was unable to take requests anymore until I restarted it. I would like to avoid this and have the default error handler send out a generic response back to the user when this occurs. I thought if I specified the defaultErrorHandler and put it inside of app.use that it would capture and handle all errors, but this does not seem to be the case? Inside of my async function for example you can see I am looking if an error was returned and if it was I send an error back to the user, but what if some other error occurs, how can I get express to capture and handle this error for me?
The defaultErrorHandler cannot handle exceptions that are thrown inside asynchronous tasks, such as callbacks.
If you define a route like:
app.get('/a', function(req, res) {
throw new Error('Test');
});
An error will be thrown, and in this case defaultErrorHandler will successfully catch it.
If the same exception occurs in an async manner, like so:
app.get('/a', function(req, res) {
setTimeout(function () {
throw new Error('Test');
}, 1000);
});
The server will crush, because the callback is actually in another context, and exceptions thrown by it will now be caught by the original catcher. This is a very difficult issue to deal with when it comes to callback.
There is more than one solution though. A possible solution will be to wrap every function that is prone to throw error with a try catch statement. This is a bit excessive though.
For example:
app.get('/a', function(req, res) {
setTimeout(function () {
try {
var x = JSON.parse('{');
}
catch (err) {
res.send(err.message);
}
}, 1000);
});
A nicer solution:
A nicer solution, would be to use promises instead, if it's possible, then for example you can declare a single errorHandler function like so:
function errorHandler(error, res) {
res.send(error.message);
}
Then, let's say you have to following function with fetches stuff from the database (I used setTimeout to simulate async behavior):
function getStuffFromDb() {
return new Promise(function (resolve, reject) {
setTimeout(function () {
resolve("{");
}, 100);
});
}
Notice that this function returns an invalid JSON string. Your route will look something like:
app.get('/a', function(req, res) {
getStuffFromDb()
.then(handleStuffFromDb)
.catch(function (error) { errorHandler(error, res) });
});
function handleStuffFromDb(str) {
return JSON.parse(str);
}
This is a very simplified example, but you can add a lot more functionality to it, and (at least theoretically) have a single catch statement which will prevent your server from crushing.

Send REST calls from Node server to third party application using OAuth

I'm implementing a server that handles chat messages. In some cases I want to access data from a JIRA instance. I'm using passport-atlassian-oauth strategy for authenticating with JIRA and BearerStrategy for requests, but my issue is that the authentication is only valid in the browser after a user has given "My Server" read and write access to JIRA. In many guides they just call res.redirect('/successfulLogin') or something similar after a successful authentication, but I would instead like to do a rest call to JIRA, process the data and send it to my connected client application.
How do I do that?
I'm completely new to all this and everything just spins around in my head. I save and have access to the token used for authentication and when I for instance navigate to .../test/access_token=?[token] in my browser it works.
passport.use(new BearerStrategy(
function(token, done) {
// Find user by token
client.smembers('access_token:' + token, function(err, replies) {
if (err) {
return done(err);
}
// if user found
// TODO: yet again, hard coded for one
if (replies.length > 0) {
console.log('SHOULD BE 1:', replies[0]);
client.hgetall('users:' + replies[0], function(err, user) {
if (err) {
return done(err);
}
if (!user) {
return done(null, false);
}
return done(null, user, {scope: 'all'});
});
}
});
}
));
As you can see it's hard coded for just one user and I'm using Redis as a "database".
passport.use(new AtlassianOAuthStrategy({
applicationURL: 'http://localhost:2990/jira',
callbackURL: '/auth/atlassian-oauth/callback',
consumerKey: RsaPublicKey,
consumerSecret: rsaPrivateKey,
clientId: 'MyBot'
},
function(accessToken, tokenSecret, profile, done) {
// Find user
client.hgetall('users:1', function(err, user) {
if(err) {
return done(err);
}
// user not found
if(!user) {
// create new user, no worries!
// TODO: HARD CODED FOR ONE USER
client.hmset('users:1', 'id', profile.id, 'access_token', accessToken, function(err, res) {
client.sadd('id:admin', '1');
client.sadd('access_token:'+ accessToken, '1');
client.hgetall(profile.id, function(err, user) {
return done(null, user);
});
});
} else {
// Update access token!
client.hmset(profile.id, 'access_token', accessToken, function() {
client.sadd('access_token:' + accessToken, '1', function() {
client.hgetall(profile.id, function(err, result) {
return done(null, user);
});
});
});
}
});
}
));
Here's the rest
app.get('/auth/atlassian-oauth',
passport.authenticate('atlassian-oauth', {session: false, scope: []}),
function(req, res) {
console.log('- Function: /auth/atlassian-oauth - should not be called)');
});
app.get('/auth/atlassian-oauth/callback',
passport.authenticate('atlassian-oauth', {session: false, failureRedirect: '/login'}),
function(req, res) {
console.log('- Function: /auth/atlassian-oauth/callback - Authentication successful!', req.user.access_token);
// Update access token!
// Should I even do this? Shouldn't I already have the correct token?
client.hmset('users:1', 'access_token', req.user.access_token, function() {
client.sadd('access_token:' + req.user.access_token, '1', function() {
client.hgetall('users:1', function(err, result) {
res.redirect('/test?access_token=' + req.user.access_token);
});
});
});
});
So now that you've seen some relevant (just tell me and I'll post more) code, how do I send a rest call to JIRA without getting a 401? :)
EDIT: Any help appreciated! You would make me really happy if you just can point me into the right direction!
Ok. I figured it out! First of all you want to save both you access token and token secret to you db in AtlassianOAuthStrategy. Second, in order to send a REST call to a third party service you can just use http request with OAuth:
var request = require('request');
var oauth = {
signature_method : 'RSA-SHA1',
consumer_key : RsaPublicKey,
private_key : rsaPrivateKey,
token : [get access_token from you db],
token_secret : [get token_secret from you db]'
};
var url = 'http://localhost:2990/jira/rest/api/2/issue/' + id;
request.get({url:url, oauth:oauth, json:true}, function (e, r, issue) {
console.log(issue)
});
Now that everything is working I'm going to start refactoring and reading some more documentation in order to make the design prettier and figure out how to use Redis properly :)

HTTP Put error when updating array: No matching document found. has no method 'send'

I seem to be having issues performing HTTP Put requests inside an array in AngularJS and ExpressJS. The issue is, when I call the HTTP Put the first time, everything works correctly. However, when I try to call a second time, it doesn't work. The following is my attempt:
When I click a button, I call perform the following HTTP Put Request:
$scope.currentUser.eventsAttending.push(event.eventName);
$http.put('/api/users/' + $scope.currentUser._id, $scope.currentUser)
.success(function(data){
console.log("Success. User " + $scope.currentUser.name);
});
Here is my User schema/model in User.model.js:
var mongoose = require('mongoose');
var Schema = mongoose.Schema;
var User = require('./user.model');
var UserSchema = new Schema({
name: String,
...
eventsAttending: [{ type: String, ref: 'Event'}]
});
I route the HTTP Put Request as so in index.js:
router.put('/:id', controller.update);
And here is my actual HTTP Put function called controller.update in User.controller.js:
// Updates an existing event in the DB.
exports.update = function(req, res) {
if(req.body._id) { delete req.body._id; }
User.findById(req.params.id, function (err, user) {
if (err) { return handleError(err); }
if(!user) { return res.send(404); }
var updated = _.merge(user, req.body);
updated.markModified('eventsAttending');
updated.save(function (err) {
if (err) { return handleError(err);}
return res.json(200, user);
});
});
};
...
function handleError(res, err) {
console.log("Error: ", err);
return res.send(500, err);
}
On the second time where I try to call the HTTP Put function (exports.update above), I always get an error in Mongoose that says:
TypeError: Object VersionError: No matching document found. has no method 'send'
at handleError (/Users/schan/test/go-v2/server/api/user/user.controller.js:131:14)
at Promise.<anonymous> (/Users/schan/test/go-v2/server/api/user/user.controller.js:43:25)
The error is basically where I call the if(err) return { handleError(err); } in the HTTP Put function and when I print out the error, I get Error undefined. I'm honestly unsure on how to debug this or what I may be doing wrong. Can anyone point me in the right direction? If so that would be great! Thanks.
You're not passing res to handleError(). Change instances of handleError(err); to handleError(res, err);

Registering Glass Timeline Notification with Node

I'm trying to register TAKE_A_NOTE with the 'mirror-api-subscription' event listener. I'm not having any luck: I can launch take a note with "my app", however, there's no console log that the event has been recognized.
I would like to recognize when the TAKE_A_NOTE function has occurred or finished, and handle the response afterwards. I do not know whether the subscription should be on a stream or if I am implementing the EventListener in a faulty manner. Your help would be greatly appreciated.
The code I am utilizing is:
// references
// http://www.recursiverobot.com/post/57348836217/getting-started-with-the-mirror-api-using-node-js
// https://www.npmjs.org/package/mirror-api-subscription
var express = require('express')
, http = require('http')
, https = require('https')
, fs = require('fs')
, googleapis = require('googleapis')
, OAuth2Client = googleapis.OAuth2Client;
var app = express();
var oauth2Client = new OAuth2Client(process.env.MIRROR_DEMO_CLIENT_ID,
process.env.MIRROR_DEMO_CLIENT_SECRET, process.env.MIRROR_DEMO_REDIRECT_URL);
// all environments
app.set('port', 8888);
app.use(express.logger('dev'));
app.use(express.bodyParser());
app.use(express.methodOverride());
app.use(app.router);
var gotToken = function () {
googleapis
.discover('mirror', 'v1')
.execute(function (err, client) {
if (!!err) {
failure();
return;
}
insertContact(client, failure, success);
insertSubscription(client, failure, success);
});
};
var insertContact = function (client, errorCallback, successCallback) {
client
.mirror.contacts.insert({
"id": "myapp",
"displayName": "myApp",
"priority": 100,
"acceptCommands": [
{"type": "TAKE_A_NOTE"}
],
"speakableName":"my app"
})
.withAuthClient(oauth2Client)
.execute(function (err, data) {
if (!!err)
errorCallback(err);
else
successCallback(data);
});
};
var insertSubscription = function (client, errorCallback, successCallback) {
client.mirror.subscriptions.insert({
"callbackUrl":"https://localhost:7777/notification",
"collection":"timeline",
"userToken":"001",
"verifyToken":"secret",
"operation":["INSERT"]
});
}
var subscription = require('mirror-api-subscription')(
function () {
})
subscription.on('locations#UPDATE',
function (notification, user, payload) {
console.log('location of user %s updated', user.id)
})
subscription.on('timeline#INSERT:LAUNCH',
function (notification, user, payload) {
console.log('subscription timeline#INSERT:LAUNCH')
})
subscription.on('timeline#UPDATE:CUSTOM',
function (notification, user, payload) {
console.log('subscription timeline#UPDATE:CUSTOM')
})
app.post('/notification', subscription.dispatcher())
app.get('/', function (req, res) {
if (!oauth2Client.credentials) {
// generates a url that allows offline access and asks permissions
// for Mirror API scope.
var url = oauth2Client.generateAuthUrl({
access_type: 'offline',
scope: 'https://www.googleapis.com/auth/glass.timeline'
});
res.redirect(url);
} else {
gotToken();
}
res.write('Glass Mirror API with Node');
res.end();
});
app.get('/oauth2callback', function (req, res) {
// if we're able to grab the token, redirect the user back to the main page
grabToken(req.query.code, failure, function () {
res.redirect('/');
});
});
app.post('/reply', function(req, res){
console.log('replied',req);
res.end();
});
var options = {
key: fs.readFileSync('./ssl/key.pem'),
cert: fs.readFileSync('./ssl/cert.pem'),
};
https.createServer(options, app).listen(7777, function() {
console.log('https listening on 7777');
});
http.createServer(app).listen(app.get('port'), function () {
console.log('Express server listening on port ' + app.get('port'));
});
There are at least two potential problems with your code:
The callbackUrl must be an internet accessible HTTPS address. "Localhost" isn't good enough, since Google's servers need to be able to resolve it. You can provide an IP address, if you have a public IP address, or use a tunnel.
You don't do anything with the result of the call to client.mirror.subscriptions.insert(). Typically, you should call it the same way you call client.mirror.contacts.insert(), which is to chain it with withAuthClient() and execute(). You'll need to call execute() if you expect it to register with the Mirror service. See https://github.com/google/google-api-nodejs-client/ for documentation about the "googleapis" package and discovery service
Possibly related to #2, but I'm not familiar with the package you're including with require('mirror-api-subscription'), which seems to handle things differently than the "googleapis" package and discovery service it offers. From the reference documentation for it, however, it isn't clear that it actually sets up the callback anywhere and is just there to verify the callbacks and dispatch to functions that do the work.
var insertSubscription = function (client, errorCallback, successCallback) {
client.mirror.subscriptions.insert({
"callbackUrl":"https://mirrornotifications.appspot.com/forward?url=callbackURL",
"collection":"timeline",
"userToken":"001",
"verifyToken":"secret",
"operation":["INSERT"]
}).withAuthClient(oauth2Client).execute(function (err, data) {
if (!!err)
errorCallback(err);
else
successCallback(data);
});
};

Express: Accessing req.session from /models/index.js

I've built a series of database queries in my express app that reside in a /models/index.js file which I can access from app.js via var express = require('express');. I am trying to populate req.session.user with a userid that is returned by a findByEmail(); function in /models/index.js.
The findByEmail(); function works fine, however I can't figure out how to store its return value in req.session. I've tried including req.session.id = result.rows[0].id; in the 'findByEmail();function, but this returns areq is not defined` error.
Am I overlooking a simple require statement in my /models/index.js file or is there another trick to accessing req.session in a module?
I've included the relevant code from /models.index.js below:
/models.index.js:
var pg = require('pg');
function findByEmail(email){
pg.connect(function(err, client, done) {
if(err) {
console.log('pg.connect error');
throw err;
}
client.query('BEGIN', function(err) {
if(err) {
console.log('client.query BEGIN error');
return rollback(client, done);
}
process.nextTick(function() {
var text = "SELECT * FROM users WHERE email = $1";
client.query(text, [email], function(err, result) {
if(err) {
console.log(err);
return rollback(client, done);
}
console.log(result);
console.log(result.rows);
console.log('id: ', result.rows[0].id);
req.session.id = result.rows[0].id;
done();
});
});
});
});
}
module.exports.pg = pg;
exports.findByEmail = findByEmail;
As far as /models/index.js knows, req is not defined, same thing with rollback. A module is a closure and you don't have access to variables defined outside of it.
If you want to do that you must pass them as parameters but it's not very good design, as #gustavohenke said: Separation of concerns.
You might want to have a callback and call it with success/error and set the session id there so you don't have to pass in into the module:
function findByEmail(email,callback){
pg.connect(function(err, client, done) {
if(err) {
console.log('pg.connect error');
throw err;
}
// Do all the async work and when you are done ...
// An error is usually passed as the first parameter of the callback
callback(err,result)
});
}
exports.findByEmail = findByEmail;
You would then call it like this:
var models = require('./models');
models.findByEmail('thedude#lebowski.com',function(err,results) {
// set session id here where you probably have access to the req object...
})

Categories

Resources