数据来自另一个调用后，在Node.js服务器中解决Promise？

Question

I have a few promises in my node server that after they all resolve the server renders to the client. I am using Promise.all([ ... that has all the data from the few promises I have.

I now however need some data from another call before one of my promises resolves. But it seems Promise.all is still resolving before I have what I need.

const myPromise = new Promise((resolve) => {
    needDataFromThisCall(someInfo)
    .then((data) => {
        return resolve(sortData(data))
    })
    .catch((error) => {
        //error handle
    })
})
.then((resolvedData) => {
    return resolvedData;
})

This does not seem to work because the final .then the resolvedData is undefined and seems to get resolved before I get into my sortData function. Does the return resolve(sortData... not end up giving its return value to the final .then ?

How should this really be done so myPromise can resolve after I have that data needed to send to sortData ?

Answer 1

Below code works fine. Assuming sortData is synchronous function, you need to resolve myPromise to get the result.

 let someInfo = [2,3,1]; let needDataFromThisCall = info => new Promise(res => setTimeout(()=>res(info), 500) ); let sortData = data => data.sort(); const myPromise = new Promise((resolve) => { needDataFromThisCall(someInfo) .then((data) => { return resolve(sortData(data)) }) .catch((error) => { //error handle }) }) .then((resolvedData) => { return resolvedData; }) myPromise.then(data => console.log('final data', data))