Using forEach to push new values into an object and returning async

Question

I'm trying to add new values into an array of objects and then returning the entire object, with the new values, to the client.

I've already tried using async/await and promises, though possibly doing that wrong. I did also read that forEach isn't async await so I tried using map too but that didn't work for me.

 // results
    const userPromise = new Promise((resolve, reject) => {
        results.forEach((pyUser) => {
            console.log(pyUser);
            // For each user attempt to look up associated data
            User.findOne({ _id: pyUser.id }, (err, user) => {
                if (user){
                    pyUser.address= 'Test address';
                }
            });
        });
        resolve();
    }).then(
        console.log(results)
    // Send results
    res.send(results)
    ).catch(
        console.log('Ooooops...')
    )

I'm hoping that results that are being sent back will include the new address property.

That doesn't look like it would solve the issue but instead a nicer way of writing it? — Stephanie Parker, Sep 24 '19 at 09:35
Yes - see the linked question at the top to see how to solve the issue — CertainPerformance, Sep 24 '19 at 09:35
Thanks - I'm not really understanding how that relates and it doesn't answer my question regarding forEach not being aware of async either. I'm trying to push onto an object too, not an array. Sorry - im still fairly new and pretty thick. Also that antipattern link you gave me doesn't look like it handles errors in that way of writing it? — Stephanie Parker, Sep 24 '19 at 10:02
`Promise.all(results.map(pyUser => User.findOne(...` and use `.findOne`'s Promise rather than callback - then you can call `.then` on the `Promise.all` call — CertainPerformance, Sep 24 '19 at 10:40
Thank you that worked for me - eternally grateful. Because I used the findOne promise I need to write a .catch() but it's actually ok if that doesnt return a user. Is it acceptable to use an empty catch ie: .catch() — Stephanie Parker, Sep 24 '19 at 11:14
It's kinda weird - usually, when there's an error, you want to *handle* it somehow, like display an error message, rather than ignore it — CertainPerformance, Sep 24 '19 at 11:37

Using forEach to push new values into an object and returning async

0 Answers0