Express4 and Formidable file upload works until I enable csrf - node.js

Question

I am working through Ethan Brown's book "Web Development with Node and Express" and it has been going well until I got to enabling csrf the multipart/form-data upload on the photo upload. I downloaded the full book code from Github, https://github.com/EthanRBrown/web-development-with-node-and-express and that does the same thing, works until csrf is enabled then it errors with:
Error: invalid csrf token
here are the bits of code I think are relevant, /meadowlark.js starting at line 100
app.use(require('cookie-parser')(credentials.cookieSecret));
app.use(require('express-session')({ store: sessionStore,
secret: credentials.cookieSecret,
name: credentials.cookieName,
saveUninitialized: true,
resave: true }));
app.use(express.static(__dirname + '/public'));
app.use(require('body-parser')());
// cross-site request forgery protection
app.use(require('csurf')());
app.use(function(req, res, next){
res.locals._csrfToken = req.csrfToken();
next();
});
// database configuration
var mongoose = require('mongoose');
var options = {
server: {
socketOptions: { keepAlive: 1 }
}
};
Then in /handlers/contest.js
var path = require('path'),
fs = require('fs'),
formidable = require('formidable');
// make sure data directory exists
var dataDir = path.normalize(path.join(__dirname, '..', 'data'));
var vacationPhotoDir = path.join(dataDir, 'vacation-photo');
fs.existsSync(dataDir) || fs.mkdirSync(dataDir);
fs.existsSync(vacationPhotoDir) || fs.mkdirSync(vacationPhotoDir);
exports.vacationPhoto = function(req, res){
var now = new Date();
res.render('contest/vacation-photo', { year: now.getFullYear(), month: now.getMonth() });
};
function saveContestEntry(contestName, email, year, month, photoPath){
// TODO...this will come later
}
exports.vacationPhotoProcessPost = function(req, res){
var form = new formidable.IncomingForm();
form.parse(req, function(err, fields, files){
if(err) return res.redirect(303, '/error');
if(err) {
res.session.flash = {
type: 'danger',
intro: 'Oops!',
message: 'There was an error processing your submission. ' +
'Pelase try again.',
};
return res.redirect(303, '/contest/vacation-photo');
}
var photo = files.photo;
var dir = vacationPhotoDir + '/' + Date.now();
var path = dir + '/' + photo.name;
fs.mkdirSync(dir);
fs.renameSync(photo.path, dir + '/' + photo.name);
saveContestEntry('vacation-photo', fields.email,
req.params.year, req.params.month, path);
req.session.flash = {
type: 'success',
intro: 'Good luck!',
message: 'You have been entered into the contest.',
};
return res.redirect(303, '/contest/vacation-photo/entries');
});
};
exports.vacationPhotoEntries = function(req, res){
res.render('contest/vacation-photo/entries');
};
and the views/contest/vacation-photo.handlebars
<form class="form-horizontal" role="form"
enctype="multipart/form-data" method="POST"
action="/contest/vacation-photo/{{year}}/{{month}}">
<input type="hidden" name="_csrf" value="{{_csrfToken}}">
<div class="form-group">
<label for="fieldName" class="col-sm-2 control-label">Name</label>
<div class="col-sm-4">
<input type="text" class="form-control"
id="fieldName" name="name">
</div>
</div>
<div class="form-group">
<label for="fieldEmail" class="col-sm-2 control-label">Email</label>
<div class="col-sm-4">
<input type="email" class="form-control" required
id="fieldName" name="email">
</div>
</div>
<div class="form-group">
<label for="fieldPhoto" class="col-sm-2 control-label">Vacation photo</label>
<div class="col-sm-4">
<input type="file" class="form-control" required accept="image/*"
id="fieldPhoto" data-url="/upload" name="photo">
</div>
</div>
<div class="form-group">
<div class="col-sm-offset-2 col-sm-4">
<button type="submit" class="btn btn-primary">Submit</button>
</div>
</div>
</form>
What is the proper way to make csrf work?
Thanks,

Answer 1

On vacation-photo GET request, you should send csrf token like below.
exports.vacationPhotoEntries = function(req, res){
res.render('contest/vacation-photo/entries', { _csrfToken: req.csrfToken()});
};
You can also catch csrf token error in your default error handler like below.
// error handler
app.use(function (err, req, res, next) {
if (err.code !== 'EBADCSRFTOKEN') return next(err)
// handle CSRF token errors here
res.status(403)
res.send('session has expired or form tampered with')
})
For more info, please check this link.

Answer 2

Append csrf token as query string to action Url..
It works!
<form class="form-horizontal" role="form" enctype="multipart/form-data" method="POST"
action="/contest/vacation-photo/{{year}}/{{month}}?_csrf={{_csrfToken}}">
</form>