然后所有的结构都无法按预期工作

Question

I am pretty new on Node stuff so I do apologise in advance if it is quite basic.

I am trying to trigger a function once, three asynchronous functions have already finished. This is my approach:

First file: ./promise.js var reqHandler = require('./asyncTesting'); var Promise = require('bluebird');

var listOfMed = ["med1","med2","med3"];

function postMethod() {
    console.log("Post done");
}

reqHandler.reqHandler(listOfMed)
    .then(function() {
    console.log("Post done");
});

The second file:

./asyncTesting.js
var Promise = require('bluebird');

function function2() {
    // all the stuff you want to happen after that pause
    console.log("Requesting json for med2");
}

function callFunction(method){
    if (method =="med2"){
        setTimeout(function2, 3000);
    }else{
        console.log("Requesting json for "+method);
    }       
}

function reqHandler(listOfMed) {
 return Promise.all(listOfMed.map(callFunction)); 
}

exports.reqHandler = reqHandler;

The expected output would be:

Requesting json for med1
Requesting json for med3
Requesting json for med2
Post done

However, what I really got on console is:

Requesting json for med1
Requesting json for med3
Post done
Requesting json for med2

Thanks in advance

Answer 1

function callFunction(method){
    return new Promise(function(resolve,reject){
        if (method =="med2"){
            setTimeout(function(){function2();resolve()}, 3000);
        }else{
            console.log("Requesting json for "+method);resolve();
        }
    });   
}

Promise.all means when all promises given finished,it will return. Your code has three promise,though there is a delayed part,but function will finished directly.