For noon, she worked with an asynchronous module, but could not get it to work properly when nesting several levels. A bit long message due to code, but please, with me, all code should work fine.
So this works fine:
var async = require ('async')
var myarr = ["Outer - A", "Outer - B"];
var myarr2 = ["Inner - A", "Inner - B"];
var innerComplete = true;
async.eachSeries (myarr, function (item, outerCallback) {
console.log ('Processing item' + item);
async.series ([
function (callback) {
takeTime (2000, item, callback)
},
function (callback) {
takeTime (1000, item, callback)
},
function (callback) {
outerCallback ();
}
], function (err) {
console.log ("--- OUTER SEQUENCE ---")
})
}, function (err) {
console.log ("--- OUTER LOOP ---")
});
function takeTime (ms, msg, callback) {
console.log ("Starting" + ms + "ms task from" + msg);
setTimeout (function () {
console.log ("Finished" + ms + "ms task from" + msg);
callback ();
}, ms);
}
And he displays everything beautifully in sequence as follows:
Processing item Outer - A
Starting 2000 ms task from Outer - A
Finished 2000 ms task from Outer - A
Starting 1000 ms task from Outer - A
Finished 1000 ms task from Outer - A
Processing item Outer - B
Starting 2000 ms task from Outer - B
Finished 2000 ms task from Outer - B
Starting 1000 ms task from Outer - B
Finished 1000 ms task from Outer - B
--- OUTER LOOP ---
But when I try to nest the following everySeries loop as follows:
var async = require ('async')
var myarr = ["Outer - A", "Outer - B"];
var myarr2 = ["Inner - A", "Inner - B"];
var innerComplete = true;
async.eachSeries (myarr, function (item, outerCallback) {
console.log ('Processing item' + item);
async.series ([
function (callback) {
takeTime (2000, item, callback)
},
function (callback) {
takeTime (1000, item, callback)
},
function (callback) {
async.eachSeries (myarr2, function (item2, outerCallback2) {
console.log ('Processing item' + item2);
async.series ([
function (callback2) {
takeTime (2000, item2, callback2)
},
function (callback2) {
takeTime (1000, item2, callback2)
}
], function (err) {
console.log ('--- INNER SEQUENCE ---')
})
}, function (err) {
console.log ("--- INNER LOOP ---")
});
outerCallback ();
}
], function (err) {
console.log ("--- OUTER SEQUENCE ---")
})
}, function (err) {
console.log ("--- OUTER LOOP ---")
});
function takeTime (ms, msg, callback) {
console.log ("Starting" + ms + "ms task from" + msg);
setTimeout (function () {
console.log ("Finished" + ms + "ms task from" + msg);
callback ();
}, ms);
}
It loses execution order when you enter the second eachSeries loop as follows:
Processing item Outer - A
Starting 2000 ms task from Outer - A
Finished 2000 ms task from Outer - A
Starting 1000 ms task from Outer - A
Finished 1000 ms task from Outer - A
Processing item Inner - A
Starting 2000 ms task from Inner - A
Processing item Outer - B
Starting 2000 ms task from Outer - B
Finished 2000 ms task from Inner - A
Starting 1000 ms task from Inner - A
Finished 2000 ms task from Outer - B
Starting 1000 ms task from Outer - B
Finished 1000 ms task from Inner - A
--- INNER SEQUENCE ---
Finished 1000 ms task from Outer - B
Processing item Inner - A
Starting 2000 ms task from Inner - A
--- OUTER LOOP ---
Finished 2000 ms task from Inner - A
Starting 1000 ms task from Inner - A
Finished 1000 ms task from Inner - A
--- INNER SEQUENCE ---
I also tried a waterfall, mapSeries, etc., but mixed up the execution sequence with the same or another way. Am I doing something wrong or doesn’t support such an asynchronous module?