nodeJs express petitions from ajax don't show error's page - node.js

Question

I have a configuration to serve a website with an error handler. It works fine with app.post requests, but it does not work with ajax petitions.
Here is my error handling middleware with an example of bad path error that works correctly:
//Bad path error
app.get('*', function(req, res, next){
next('404'); //This works fine
});
//Errors control Middleware
app.use(function (err, req, res, next) {
if (typeof (err) === 'string') {
var lang = require(path.join(__dirname, '_public', 'errors', 'lang', process.env.LANG + '.js'));
return res.render(path.join(__dirname, '_public', 'errors', err), {lang});
} else {
log.error(err);
var lang = require(path.join(__dirname, '_public', 'errors', 'lang', process.env.LANG + '.js'));
return res.render(path.join(__dirname, '_public', 'errors', '500'), {lang});
}
});
when I navigate to a wrong url (some url that isn't defined on my server) it goes correctly to the defined error page (404, that is an .hbs). The problem is that this method doesn't seem to work with ajax petition like the next one:
jQuery.ajax({
type: 'POST', //I have the same problem with 'GET'
url: '/componentName/methodName',
data: {
accessToken: localStorage.token
},
}).then(function success(data) {
//TODO
}, function error(err) {
console.log(err);
})
This piece of code is for server side:
app.post("/componentName/methodName", function (req, res, next) {
var token = req.body.accessToken;
var decodedToken = jwt.decode(token);
var user_id = decodedToken.payload.user_id;
model.getTasks(user_id).then(function (modelData) {
res.send(modelData); //This works fine
}, function () {
next('500'); //This broke the page and doesn't show error page
});
});
What could be the problem for not showing the error from ajax? Is my syntax correct?
new: The problem must be on the ajax success, because if I change the 'post' by 'get' in ajax and the app.get route I still having the same problem, but if I call the method directly from URL (not ajax) it works. Any idea?
new2: If I put this code on success:
jQuery('body').html(data);
it shows the error page after a few seconds. I need to do this automatically (and without those fews seconds) when any error is trhowing from the server, because I don't know if it will be ok or if is an error and the lag seconds is a problem too. Probaly anything on the server could be wrong? and it inject the error page inside the older page, so isn't a solution

Answer 1

model.getTasks(user_id).then(function (modelData) {
res.send(modelData); //This works fine
}).catch(function () {
next('500');
})
Use catch block