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node.jsexpresspassport.jspassport-local

Undefined message variable NodeJS


I have been following this tutorial for my node app to implement authentication: https://scotch.io/tutorials/easy-node-authentication-setup-and-local

The issue I am having is I'm getting this error when running the app: (my code is exacltly how it should be according to the above website).

enter image description here

I tried searching for an answer but the best I could get is adding this function to my server code:

app.use(function(req, res, next){
    res.locals.message = req.flash();
    next();
});

This loads the application without any errors however, the message does not seem to be displayed in my front-end. Not exactly sure why but Im getting this problem with this project only, I can implement messages without any issues in my other projects.

I've added my github link below but heres bits of my code:

routes.js

app.post('/signup', passport.authenticate('local-signup', {
    successRedirect : '/dashboard',
    failureRedirect : '/#contact',
    failureFlash : true
}));

passport.js

if (user) {
    return done(null, false, req.flash('signupMessage', 'Email already in use!'));
}

index.ejs

<% if (message.length > 0) { %>
    <div class="alert alert-danger"><%= message %></div>
<% } %>

Github project: https://github.coventry.ac.uk/salmanfazal01/304CEM-Back-End


Solution

  • From the error i think you didn't pass the variable message correctly to the ejs view.

    So you have 2 solutions

    1- In your routes.js file you need to pass message while rendering index view, this is how the example you are following is done.

    So Change

    //GET homepage
    app.get('/', function(req, res) {
        res.render('index');
    }); 
    

    To

    //GET homepage
    app.get('/', function(req, res) {
        res.render('index' , {message: <your data> });
    }); 
    


    2- using res.locals and res.flash which is the solution you found, but you are not actually passing any values in req.flash()

    So replace this code

    app.use(function(req, res, next){
        res.locals.message = req.flash();
        next();
    });
    

    with

    app.use(function(req, res, next){
        req.flash("info" , "first message"); //here you add message under type info
        req.flash("info" , "second message"); // here you add another message under type info
    
        next();
    });
    

    and in your route.js

        app.get('/', function(req, res) {
            res.render('index' , {message : req.flash("info")}); //set message from req.flash type info
        });
    
        //or
    
       app.get('/', function(req, res) {
            res.locals.message = req.flash("info"); //set locals.message from req.flash type info 
            res.render('index');
        });