async.series() continues to execute next functions despite errors - node.js

Question

I'm using the async.series() control flow from caolan's async module. U
nlike the doc's explanation that it should excute all functions in sequence, one after the other and stop when one calls its callback with an error; mine actually calls the main callback if one of the functions gets an erro but then happily continues to execute the rest of the functions in sequence.
async.series([
function (cb) {
if (!req.body.join_firstname || !req.body.join_lastname || !req.body.join_email || !req.body.join_password) {
req.flash('error', 'Please enter a name, email and password.');
cb(true);
}
if (req.body.join_password !== req.body.join_passwordConfirm) {
req.flash('error', 'Passwords must match.');
cb(true);
}
if (req.body.join_email !== req.body.join_emailConfirm) {
req.flash('error', 'Emails must match.');
cb(true);
}
cb(null);
},
function (cb) {
keystone.list('User').model.findOne({
email: req.body.join_email
}, function (err, user) {
if (err || user) {
req.flash('error', 'User already exists with that email address.');
cb(true);
}
cb(null);
});
},
function (cb) {
var userData = {
name: {
first: req.body.join_firstname,
last: req.body.join_lastname
},
email: req.body.join_email,
password: req.body.join_password
};
var User = keystone.list('User').model,
newUser = new User(userData);
newUser.save(function (err) {
if (err) {
//if there's an error, don't send activation mail
cb(err);
} else {
newUser.activationEmail(function (err) {
if (err) {
//if we can't send activation email,
//delete user from db to prevent re-registration failing because of non-unique email
keystone.list('User').model.findOne({
email: req.body.join_email
}).remove(function (err) {
req.flash('error', "Couldn't send an activation email. Contact support if this problem persists.");
cb(true);
});
} else {
cb(err);
}
});
}
});
}
], function (err) {
if (err) return next();
req.flash('success', "Hi, " + req.body.join_firstname + "! We've sent you an activation email. Please check your inbox and spam folder.");
return res.redirect('/');
});
For example, when I purposely enter the wrong password confirm value, it throws an error, executes the callback and return next(); and then just continues, even saving the user in the db. Obviously that was not the intended result.
Anyone got an idea what I'm doing wrong here?

Answer 1

If you want execution of a current function to stop, it's not enough to call a callback. For instance:
function(cb) {
if (!req.body.join_firstname || !req.body.join_lastname || !req.body.join_email || !req.body.join_password) {
req.flash('error', 'Please enter a name, email and password.');
cb(true); // will add this callback to the stack
}
// continuing here
// ...
}
Either change your if-then-construct:
function(cb) {
if (!req.body.join_firstname || !req.body.join_lastname || !req.body.join_email || !req.body.join_password) {
req.flash('error', 'Please enter a name, email and password.');
cb(true); // will add this callback to the stack
} else if (req.body.join_password !== req.body.join_passwordConfirm) {
//...
}
// no more code here
}
or return:
function(cb) {
if (!req.body.join_firstname || !req.body.join_lastname || !req.body.join_email || !req.body.join_password) {
req.flash('error', 'Please enter a name, email and password.');
return cb(true); // will add this callback to the stack and return
}
// will only be executed if the if is false
// ...
}