API routes with Promise.all

[Nick-Mazuk]

Whenever I use Promise.all inside an API route, I get the following error.

API resolved without sending a response for /api/route, this may result in stalled requests.

I suspect NextJS assumes that since it's reached the end of the function and hasn't found a res.send() that the request is stalled?

Here's a barebones file that demonstrates this behavior:

// api/route
const promise = () => {
    return new Promise((resolve, reject) => {
        resolve()
    })
}

export default (req, res) => {
    Promise.all([promise]).then(() => {
        res.statusCode = 200
        res.json({ message: 'Success!' })
    }).catch((e) => {
        res.statusCode = 200
        res.json({ message: 'Success!' })
    })
}

[timneutkens]

You need to await the promise.

[Nick-Mazuk]

That works, thanks!