return value inside db function on res render

Question

i want make a helper and will be used in my view (pug), so i send a function as data to the view file, but the problem is, my helper / passed function wont return a value or == undefined in my view, pug, thanks

    app.get('/admin/pengguna', function(req,res){
    db.all("SELECT * FROM main_posts WHERE wdyw='2'", function(err, rows) {
        //var r = db.all("SELECT * FROM main_posts WHERE wdyw='1' AND ")
        if (!err) {
            res.render('admin/pengguna', {
                path: req.path,
                pengguna : rows,
                useringroup: function(w) {
                    db.all("SELECT * FROM main_posts WHERE wdyw='1' AND identity= $w", { $w: w }, function(err, result){
                        return result.lenght;
                    })
                }
            })
        }
    })
})

do you understand why the `db.all` after `return w` wont execute? — Jaromanda X, Jun 07 '17 at 02:57
the result is that the inner `db.all` won't run - is this what you expect? However, I don't think that's the issue you are talking about, it seems like you don't understand asynchronous code — Jaromanda X, Jun 07 '17 at 04:04
wont return sir, i check that with console.log, and its showing a total row, but when i return it, the result is undefined — Kunto Handoko, Jun 07 '17 at 05:33

score 0 · Answer 1 · answered Jun 07 '17 at 08:39

Wait for the db to return the data and then render the view. Your view can not make a call directly to db. This is why we use MVC (Model View Controller). You need to fetch all the data in your controller and then pass it to view.

You will need to use something like this,

app.get('/admin/pengguna', function(req,res){
    db.all("SELECT * FROM main_posts WHERE wdyw='2'", function(err, rows) {
        //var r = db.all("SELECT * FROM main_posts WHERE wdyw='1' AND ")
        if (!err) {
            db.all("SELECT * FROM main_posts WHERE wdyw='1' AND identity= $w", { $w: w }, function(err, result){
                res.render('admin/pengguna', {
                    path: req.path,
                    pengguna : rows,
                    useringroup: result.length
                })
            })

        }
    })
})

Also you will need to adjust your code for w. Before you were getting it from the function you passed to the view. You'll need to get its value by any other method or modify the query.

return value inside db function on res render

1 Answers1