Having issues with JWT and express-JWT - node.js

I'm testing out express-jwt and jsonwebtokens. I've never used this before and would like some help!
I've got the basics setup done and I only have one protected route.
app.use('/api', expressJWT({secret: 'cat'}));
Unfortunatley, i'm not able to access '/api' because it gives me this error
UnauthorizedError: No authorization token was found
If I use POSTman and issue a GET request with the following header
Authorization -> Bearer eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJ1c2VybmFtZSI6ImJhc2hpciIsImlhdCI6MTQ1MTQ0MjM4NywiZXhwIjoxNDUxNDQyNjg3fQ.CnaLvS_oCEy_mp_9MSAmTTylJqQMI2Qlq9V3emAmN3E
Everything works fine and I'm able to access the content in '/api'.
But my issue is in my express application, specifically when I try to redirect the user to a new protected route.
User logs in and I create a new jwt token and redirect the user to '/api'
router.post('/login', passport.authenticate('local'), function (req, res) {
myToken = jwt.sign({
username: req.body.username
}, 'cat', {expiresIn: 60*5});
res.redirect('/api');
});
In this route, I set the headers and render the page.
router.get('/api', function (req, res) {
res.render('index', {user: req.user});
});
Unfortunately, I get the following error
UnauthorizedError: No authorization token was found
My goal is to be able to redirect a user to a protected route.
From my understanding, since /api is a protected route, express-jwt should be setting my authorization headers. Even if I try to manually set my headers using a middleware I still get an error.
Any help is greatly appreciated!
Thanks!

try something like res.redirect('/api?token ' + myToken);
Then to receive query inputs change the expressJWT normal function with a custom function.
app.use('/api', expressJWT({
secret: 'cat',
credentialsRequired: false,
getToken: function fromHeaderOrQuerystring (req) {
if (req.headers.authorization && req.headers.authorization.split(' ')[0] === 'Bearer') {
return req.headers.authorization.split(' ')[1];
} else if (req.query && req.query.token) {
return req.query.token;
}
return null;
}
}));
This was mostly from reading the expressJWT docs and other stack answers.

Related

Unable to get decoded payload of JWT from auth0/express-jwt library

I'm trying to obtain the decoded JWT payload using the express-jwt from auth0 as a middleware in my expressjs application. For the token to be used for authentication, I have to use a custom async function to process the token first before providing it to express-jwt. I understand that I can write a custom function under the getToken parameter as documented in express-jwt as shown below, but it does not work with async function.
const jwt = require("express-jwt");
const checkJwt = jwt({
secret: 'hello world !',
algorithms: ['HS256'],
credentialsRequired: false,
getToken: function fromHeaderOrQuerystring (req) {
if (req.headers.authorization && req.headers.authorization.split(' ')[0] === 'Bearer') {
return req.headers.authorization.split(' ')[1];
} else if (req.query && req.query.token) {
return req.query.token;
}
return null;
}
});
module.exports = checkJwt;
To overcome this limitation, I included the jwt() as part of a larger middleware function that first process the token, and then providing it to jwt(). The unprocessed token is attached to my headers. My code structure is as follows:
const myMiddleware = async (req, res, next) => {
// Process Token First
const processedToken = await functionToProcessToken(req.headers.tokenLocation);
// Jwt Authentication
jwt({
secret: 'hello world !',
algorithms: ['HS256'],
credentialsRequired: false,
getToken: processedToken
});
next();
});
module.exports = myMiddleware;
While I'm able to authenticate my routes without any issue, I need to get the decoded JWT payload for further uses. By default, as written in the documentation, the decoded payload should have been attached to req.user, but when I try to console.log it, it shows undefined. I have also tried adding requestProperty but it does not work as well. The documentation for resultProperty is not very clear, so I could not get that to work too.
I very much appreciate if someone can point me towards right direction to help me achieve the expected outcome for my middleware. Thank you!

Using .unless in express.js to avoid jsonwebtoken verification for a couple of routes

I don't want jwt to verify the token for login and register request. Once the user is loggedIn a token is created using jwt.sign() after that to verify every request, I am using jwt.verify()
I think there is a way to use .unless with app.use(). I did install express-unless but it still doesn't seem to run.
app.use(function(req,res,next){
// console.log(req.body);
var token=req.body.authtoken || req.query.authtoken || req.headers['authtoken'] ||req.headers.authorization;
console.log(token);
jwt.verify(token,'my-secret-key',function(err,decoded){
if(err){
res.send({
err:true,
msg:'Invalid Request'
});
}else{
req.decoded=decoded;
next();
}`enter code here`
})
}).unless({path:['/register','/login']});

Authentication in Express Middleware

I'm a little new to this. I have REST API made with Node.js and Express.js. Some routes have authentication middleware. To use those routes, a header has to be set with the user's auth token which gets verified. I have been doing this with no problem with static sites using local storage. I'm making my first dynamic site now (using Express) and for certain routes I have middleware that loads all the data I need to display the page. How do I access and use auth tokens now that I don't have local storage's help?
EDIT(for clarification):
So here is one of my api routes that fetches all transactions from a database(mongoDB).
app.get('/transactions', authenticate, (req, res) => {
Transaction.find().then((transaction) => {
res.send({transaction});
}, (e) => {
res.status(400).send();
});
});
This is the authentication middleware that gets run.
var authenticate = (req, res, next) => {
var token = req.header('x-auth');
User.findByToken(token).then((user) => {
if (!user) {
return Promise.reject();
}
req.user = user;
req.token = token;
next();
}).catch((e) => {
res.status(401).send();
});
};
Now on my express webserver, I have a following route, where I use getTransactions to fetch all my data. (which I display with handlebars)
router.get('/orders', getTransactions, (req, res) => {
res.render('orders.hbs', {
transaction: req.transactions.data.transaction
});
});
and this is the middleware
var getTransactions = (req, res, next) => {
axios.get('https://serene-wave-28270.herokuapp.com/transactions')
.then((response) => {
req.transactions = response;
console.log(req.transactions.data.transaction);
next();
}).catch((e) => {
console.log(e);
})
}
So when I was just making a static site without using express as a webserver, I would just have the user sign in and save the auth token in local storage. Also, I should note that the first two blocks are from my api, and the bottom two from webserver, both hosted separately on Heroku. I'm not sure if that's standard design so I thought I should mention it.
There's not a whole lot of detail in your question for exactly what you're trying to do, but I can explain the general concepts available to you in Express:
The usual scheme for Express is to authenticate the user initially and then set a session cookie that indicates that user has been authenticated. Since the cookie is automatically stored by the browser and then automatically sent from the browser to the server with every request, you will have that cookie which the server can then use to identify a server-side session and then you can use any info you want from the session (user identify or other state you store in the session object) when creating pages or responding to API requests for that user.
The NPM module express-session handles much of this work for you as it will automatically create a session object, a session cookie and hook the two together on every request.
If, on the other hand, you already have an auth token in the client and you just want that to be automatically communicated to the server with every request, then you can just put that auth token into a cookie and have the server look for it in the cookie on each request. You can even make it a bit more secure by setting the cookie to HttpOnly so that the auth token cannot be accessed from client-side Javascript (this will not affect the server's ability to access it).
There is not much detail in your question but here are a few thoughts.
You can either use cookies (as detailed by #jfriend00 below) or use the requests' headers to check for a valid authorization token (which I describe below)
In Express you can access the headers through req.headers so you can just write a middleware that you will call before your current middleware loading all the data to ensure that the user is authorized to continue (calling next() to call the next middleware) or using a custom Error type to flag the authentication error if he is not (calling next(err) to skip all the other middleware and jump to your error middleware)
For example (assuming you have a subclass of Error named AuthorizationError defined somewhere):
const express = require('express');
const AuthorizaztionError = require('<some path>');
const app = express();
function checkAuthTokenMiddleware(req, res, next) {
if (req.headers && req.headers.authorization) {
let token;
const parts = req.headers.authorization.split(' ');
if (parts.length == 2) {
const [scheme, credentials] = parts;
if (/^Bearer$/i.test(scheme)) { // or any other scheme you are using
token = credentials;
}
if (token === undefined) {
// access token - missing
return next(new AuthorizationError(
"Invalid access token.", // error_description
"invalid_token" // error
));
}
// add something here to ensure the token is valid
return next();
}
} else {
// No authorization header => invalid credentials
return next(new AuthorizationError(
"Authorization header required.", // error_description
"invalid_request" // error
));
}
}
// Add this in your route declaration
app.use(
"/auth/test",
checkAuthTokenMiddleware,
function(req, res, next) {
// do something
}
);
// this must come last
app.use(function errorMiddleware(err, req, res, next) {
// return something
if (err instanceof AuthenticationError) {
// do something for example
res.status(401).send(err.error_description);
} else {
// generic error handling, for example
res.status(500).send("Error "+err);
}
})
// ...

Logging users in via Express / Auth0 back-end

Auth0 documentation describes how to set up express-jwt middleware to protect endpoints. The trouble is that the documentation doesn't seem to cover how you get a valid JWT in the first place.
On the angular side, there's documentation on using angular plugins to implement a login page, that's fine. How would one implement a route using express that would take a username/password and return to the client the appropriate JWT such that subsequent requests would be authorized?
I think I may be missing a basic concept about JWT here; via Auth0, when using Username-Password-Authentication, my guess is that Auth0 acts as the repo for those credentials. There's documentation out there about wiring passport to auth0 and JWT, the problem with those is that this documentation assumes that the username/password database is some MongoDB instance locally...I want to avoid that type of setup which was an initial attraction with auth0.
Are there sample projects that cover this, showing how to get a valid JWT on a back-end, without some separate front-end angular app requesting it first?
I use passport.js built in local strategy for authentication and store user information in a JWT that I read on routes that require authorization.
User id's can be serialized/deserialized into and out of the express sessionto obtain the user identifier using the auth token (JWT) in the request. This is in my opinion the best approach since it limits the amount of data stored on the client and provides better security than storing any user information. Here's an example of this in express:
//Set a session secret
var secrets = { sessionSecret: process.env.secret || 'my secret string'};
//Require express-jwt and set a secret for the cookie
var expressJwt = require('express-jwt');
var validateJwt = expressJwt({ secret: secrets.sessionSecret });
//Returns a jwt token signed by the app secret
var signToken = function(id) {
return jwt.sign({
id: id
}, secrets.sessionSecret, {
expiresInMinutes: 60 * 24 // 24 hours
});
};
//Set token cookie directly
var setTokenCookie = function(req, res) {
if (!req.user) {
return res.status(404).json({
message: 'Error during user validation'
});
}
var token = signToken(req.user.id, req.user.role);
res.cookie('token', JSON.stringify(token));
};
//Check to see if user is authenticated (call this when a route is requested)
var isAuthenticated = function(req, res, next) {
// allow access_token to be passed through query parameter as well
if (req.body && req.body.hasOwnProperty('access_token')) {
req.headers.authorization = 'Bearer ' + req.body.access_token;
}
// Validate jwt token
return validateJwt(req, res, next);
};
You can use these methods as middleware in express. Say the above code was token.js, you can force it to execute on each request to a route like this:
app.get('/employee', token.isAuthenticated, employeeController.getEmployees);
I haven't worked with angular but it works great on the backbone projects i've worked on and this process should work with any browser based client that can supply a X-auth cookie on each request. You can do this by using the ajax setup:
$(document).ajaxSend(function(event, request) {
var token = readCookie('token');
if (token) {
request.setRequestHeader('authorization', 'Bearer ' + token);
}
});
Here is an example of middleware that validates a users login and returns a token to the client that can be used on subsequent requests:
var validateLogin = function (req, res, next) {
var username = req.params.username;
// Authenticate using local strategy
passport.authenticate('local', function(err, user, info) {
if (err) {
return next(err);
}
if (!user) {
return res.status(404).json({
info: [{
msg: info.message
}]
});
}
// Send user and authentication token
var token = token.signToken(user.id, user.role);
res.cookie('token', token);
res.render('index', {token: token, user: user});
})(req, res, next);
};
#FrobberOfBits
This is to answer the follow-up Q posted by FrobberOfBits on Feb 6, 2016 at 3:04
I use auth0 for local + social media authentication.
The way auth0 works is, you hand over the approach to authenticate to auth0 ...either it be local with db or social media.
It is a bundled approach where local db and social media authentication is all bundled and provided as a service to you by auth0.
Hope this helps.

How to set authorization headers with nodejs and express

I am setting up a site with nodejs, express, mongoose and swig template following this tutorial :
Authenticate a Node.js API with JSON Web Tokens
In this tutorial the author uses Postman to set the token in the header.
I have googled for days to find out how I can set the jwt token in the header of my site, but it is not working for me.
If you want the client to include the token in it's request headers, you can use a cookie parser with express. (HTML5 Web Storage is another option). About Cookies:
Express can set the response headers to tell the client "add the token to a cookie".
Once the client sets the cookie with the token, the token will be in the client's request headers for each request. Let's get to baking with a little
npm install cookie-parser
Sprinkle on some
var cookieParser = require('cookie-parser')
app.use(cookieParser())
Access and set a cookie:
app.use(function (req, res, next) {
var cookie = req.cookies.jwtToken;
if (!cookie) {
res.cookie('jwtToken', theJwtTokenValue, { maxAge: 900000, httpOnly: true });
} else {
console.log('let's check that this is a valid cookie');
// send cookie along to the validation functions...
}
next();
});
You will probably want to do these things with the cookies (or whatever method you go with in the end):
set the cookie to hold the token when a user is authenticated.
check the cookie header value before allowing access to protected
routes.
send back an unauthorized status if a user doesn't have their token
when they are trying to access api routes that require a token.
May help someone in future...
Storing token in cookie with httpOnly:true flag is pretty secure from XSS attack but it can be vulnerable to CSRF attack.
Adding custom request headers for all routes in express using a middleware might be a feasible solution like that:
var token;
//asign 'accessToken' to 'token' in app.post('/login')
token=accessToken;
app.all('*' , (req, res, next) => {
if (!token) {
console.log('token: undefined');
} else {
req.headers.authorization = 'Bearer ' + token;
}
next();
});
this will add authorization=Bearer <token> header in each and every get request coming from browser. Now verify token in each secure route by adding this middleware:
let in app.get('/dashboard')
const authenticateToken=(req, res, next)=>{
var authHeader=req.headers['authorization'];
var token=authHeader && authHeader.split(' ')[1];
if(token==null){
return res.sendStatus(401);
}
jwt.verify(token, process.env.JWT_ACCESS_TOKEN, (err, user)=>{
if(err){
return res.sendStatus(403);
}
req.user=user;
next();
})
}
//in app.get(...)
app.get('/dashboard', authenticateToken ,()=>{
//stuff for authorized user
})
In case if you defined app.post('/login') in another file then,
export addHeader middleware as under:
//var to access token outside app.post('/login') route
var token;
app.post('/login' , (req , res)=>{
//authenticate the user
//create token
const accessToken=jwt.sign(user, secretKey);
//assign 'accessToken' to 'token' var
token=accessToken
//redirect to secure route
res.redirect('dashboard');
}
//middleware to add in your 'index.js' or 'app.js' file.
//export it only if you define app.post('/login') in another file
exports.addHeader = (req, res, next) => {
if (!token) {
console.log('token: undefined');
} else {
req.headers.authorization = 'Bearer ' + token;
}
next();
}
In index.js or app.js
//import file in which app.post('/login') is defined. let it is defined in controller/auth
const authController=require('./controller/auth');
//to add custom header in all routes
app.all('*', authController.addHeader);

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