javascript - Problem with asyncawait while using .forEach - Stack Overflow

I'm making a simple Redis' request which is supposed to return all VALUES (not keys) in my database. The problem is that my function returns tab before the .forEach even starts. Why do I know that? My console.log(tab)'s result is printed before console.log(cards) for each iteration. My interpreter also tells me inside the .forEach function that "Promise returned from forEach argument is ignored". What have I done wrong there? Why isn't async/await working inside .forEach?

router.get("/", async (req, res) => {
    try {
        const keys = await client.keys("*")
        //console.log(result)
        const tab = []
        await keys.forEach(async (key) => {
            const cards = await client.smembers(key)
            console.log(cards)
            tab.push(cards)
        })
        console.log(tab)
        return res.send(tab)
    } catch (err) {
        console.error(err)
    }

});

I'm making a simple Redis' request which is supposed to return all VALUES (not keys) in my database. The problem is that my function returns tab before the .forEach even starts. Why do I know that? My console.log(tab)'s result is printed before console.log(cards) for each iteration. My interpreter also tells me inside the .forEach function that "Promise returned from forEach argument is ignored". What have I done wrong there? Why isn't async/await working inside .forEach?

router.get("/", async (req, res) => {
    try {
        const keys = await client.keys("*")
        //console.log(result)
        const tab = []
        await keys.forEach(async (key) => {
            const cards = await client.smembers(key)
            console.log(cards)
            tab.push(cards)
        })
        console.log(tab)
        return res.send(tab)
    } catch (err) {
        console.error(err)
    }

});

• javascript
• node.js
• redis

Share Improve this question Follow asked Nov 3, 2021 at 17:29 crazyfrogcrazyfrog 24711 gold badge55 silver badges1313 bronze badges 3

• forEach doesn't return a promise which is why you're getting that warning. – Andy Commented Nov 3, 2021 at 17:31
• how about reduce or map? would it work with them? I'd like to avoid using loops – crazyfrog Commented Nov 3, 2021 at 17:37
• You'll still be iterating over an array with map or reduce. Maybe create an array of promises and await Promise.all instead. – Andy Commented Nov 3, 2021 at 20:20

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1 Answer 1

Sorted by: Reset to default 7

forEach is not meant to work with async functions. You can use a for ... of loop instead.

for(const key of keys){
    const cards = await client.smembers(key)
    console.log(cards)
    tab.push(cards)
}