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I have an async function songAlreadyInQueue that will return true if an ID is found in a database, false otherwise. I want to use the function like such:

if(!songAlreadyInQueue(ref, id)){
  // do stuff
}

But I know that since it's an async function, I have to wait for the result to e back before I truly know if it's true or false. What I have above is always false so I tried this:

songAlreadyInQueue(ref, id).then((wasFound) => {
                                console.log("wasfound = " + wasFound)
                                if(!wasFound){
                                    //do stuff
                                }
                            })

But that doesn't work either. What is the proper way to wait for this async function to finish? This is what my async function looks like (simplified):

async function songAlreadyInQueue(requestQueueRef, requestID) {
    var querye = requestQueueRef.where("id", "==", requestID)
        .get()
        .then((snap) => {
            snap.docs.forEach(doc => {
                if (doc.exists) {
                    console.log("**************FOUND REQUEST IN QUEUE ALREADY!")
                    return true
                }
            })
            return false
        })
    return querye // not sure if correct. Is this "returning a promise"?
}

I have an async function songAlreadyInQueue that will return true if an ID is found in a database, false otherwise. I want to use the function like such:

if(!songAlreadyInQueue(ref, id)){
  // do stuff
}

But I know that since it's an async function, I have to wait for the result to e back before I truly know if it's true or false. What I have above is always false so I tried this:

songAlreadyInQueue(ref, id).then((wasFound) => {
                                console.log("wasfound = " + wasFound)
                                if(!wasFound){
                                    //do stuff
                                }
                            })

But that doesn't work either. What is the proper way to wait for this async function to finish? This is what my async function looks like (simplified):

async function songAlreadyInQueue(requestQueueRef, requestID) {
    var querye = requestQueueRef.where("id", "==", requestID)
        .get()
        .then((snap) => {
            snap.docs.forEach(doc => {
                if (doc.exists) {
                    console.log("**************FOUND REQUEST IN QUEUE ALREADY!")
                    return true
                }
            })
            return false
        })
    return querye // not sure if correct. Is this "returning a promise"?
}

• javascript
• asynchronous
• async-await

Share Improve this question Follow asked Jun 13, 2019 at 2:04 Isaac PerezIsaac Perez 59044 gold badges1717 silver badges3333 bronze badges 5

• 2 The way you tried that "doesn't work" is basically the right way to do it. What exactly doesn't work about that way? – Joseph Sible-Reinstate Monica Commented Jun 13, 2019 at 2:09
• "Is this "returning a promise"?" yes – Phil Commented Jun 13, 2019 at 2:12
• @JosephSible wasFound is always false – Isaac Perez Commented Jun 13, 2019 at 2:13
• That's because the return value of the forEach callback is not considered – Phil Commented Jun 13, 2019 at 2:16
• @Phil ooooh so I was returning true for the forEach callback instead of returning true for songAlreadyInQueue? – Isaac Perez Commented Jun 13, 2019 at 2:21

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1 Answer 1

Sorted by: Reset to default 6

With an async function you should use await instead of then() so you're not creating another anonymous function. You are returning from an anonymous function rather than the async function. try this.

async function songAlreadyInQueue(requestQueueRef, requestID) {
  var snap = await requestQueueRef.where("id", "==", requestID).get()
  var found = false;
  snap.docs.forEach(doc => {
    if (doc.exists) {
      console.log("**************FOUND REQUEST IN QUEUE ALREADY!")
      found = true
    }
  })
  return found
}

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