You should still use async
but you need async.waterfall
for that. Here is what you need to consider:
A main method to call your async
function:
var getInformation = function(){
async.waterfall([
//Array of your functions in order, we will be back here later
], function (err) {
if(err){
console.log(err);
}else{
console.log('Everything OK!');
}
);
}
Then you need your functions to be async
friendly, that means you should use callbacks and give your data from one function to another. Something like this:
function findUser(callback){
//Do something
if('Everything OK'){
callback(err, yourData); //err should be null if everything is OK and yourData should be the data that you wanna use in your next function. e.g. schoolId
}else{
callback(err); //Something was wrong, "err" should have something different to null
}
}
function findSchool(callback, schoolId){ //Note that we receive the parameter schoolId here but not in the first function
//Do something
if('Everything OK'){
callback(err, yourData); //err should be null if everything is OK and yourData should be the data that you wanna use in your next function. e.g. schoolName
}else{
callback(err); //Something was wrong, "err" should have something different to null
}
}
function findStudents(callback, schoolName){
//Do something
if('Everything OK'){
callback(err); //err should be null if everything is OK if this is the last function maybe we don't need to send back more data from here
}else{
callback(err); //Something was wrong, "err" should have something different to null
}
}
Then you should call your functions in your main method:
var getInformation = function(){
async.waterfall([
findUser,
findSchool,
findStudents
//Note that there is no need to tell the functions the parameters they are sending or receiving here
], function (err) {
if(err){
console.log(err);
}else{
console.log('Everything OK!');
}
);
}
And that's it, you have 3 functions that should be executed one after the other and no callback hell is needed.
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