How to use two MongoDB collections in my Express router?

Question

router.get('/home', ensureAuthenticated, (req, res) => res.render('home', {user_mv: req.user, post_mv: req.post1}));

//Create topic page
router.get('/create-topic', ensureAuthenticated, (req, res) => res.render('create-topic', {user_mv: req.user}));


//Post handle
router.post('/create-topic', (req, res) => {
    const {user_id, title, category, vista, description} = req.body;
    let error2= [];
    if(!title || !category || !vista || !description) {
        error2.push({msg: 'Please check all fields.'});
    };

    if(error2.length > 0){
        res.render('create-topic', {  
            error2,
            title,
            category,
            vista,
            description
        });
    }else {
        //Validation passed
        Post.findOne({title: title})
        .then(post1 => {
            if(post1){
                //User exists
                error2.push({msg: 'Title is already used.'});
                res.render('create-topic', {
                    error2,
                    title,
                    category,
                    vista,
                    description
                });
            } else {
                const newPost = new Post({
                    user_id,
                    title,
                    category,
                    vista,
                    description
                });
                newPost.save()
                    .then(post1 => {
                        res.redirect('/home');
                    })
                    .catch(err => console.log(err));
                };
            });
    };        
});



module.exports = router;

<div class="posts__content">
    <a href="#">
       <h3><%= post_mv.title %></h3>
    </a>
</div>

When logging into my website a user can create a post that inserts into MongoDB with the user's id included. I'm trying to display the title of the 1 post I have in my collection but I get an error that says 'cannot read 'title'property of undefined. Can anyone tell me what I am doing wrong?

Answer 1

It looks like you are not passing the post to your ejs. So there is no post_mv object, and so it undefined and has no properties.

res.redirect('/home',{post_mv:post1});

I may be wrong, but post1should be the new post object with the title you want as a property returned after saving.