Sailsjs Nested Callback In Async Waterfall Function Not Returning Correct Value

I'm creating an application with SailsJS. I have a question about using callbacks within an Async waterfall and Async each. I've got two functions inside an async waterfall functi

Solution 1:

When you use async's function you should you should use you callback once you are done with operations you want to perform. for example:

async.waterfall([
    function(cb1){
        model1.find().exec(function(err,rows1){
            if(!err){
                model2.find({}).exec(function(err,rows2){
                    var arr=[rows1,rows2];
                    cb1(null,arr);
                });
            }elsecb1(err);
        })
    },function(arr,cb2){
    /**
     * here in the array....we will find the array of rows1 and rows2 i.e.[rows1,rows2]
     * */
        model3.find().exec(err,rows3){
            if(!err){
                arr.push(rows3);
            //  this arr will now be [rows1,rows2,rows3]
            }
            elsecb2(err);
        }
        cb1(null,arr);
    }],
    function(err,finalArray){
        if(err){
        //  error handling
        }
        else{
        /**
         * in finalArray we have [rows1,rows2] ,rows3 is not there in final array
         * beacause cb2() was callbacked asynchronously with model3.find().exec() in second function
         */
        }
    });

so according to me your code should be like

async.waterfall([
        function(callback){
            // native MongoDB search function that returns an Array of Objects
        },
        function(result, callback){
            async.each(resultAll, function (location){
                Model.find({location:'56d1653a34de610115d48aea'}).populate('location')
                    .exec(function(err, item, cb){
                        console.log (item) // returns the correct value, but the value cant be passed to the outer functioncallback(null, yourData);
                        /**
                         * yourData is the data whatever you want to recieve in final callbacks's second parameter
                         * i.e. callback(null,item) or callback(null,[result,item]) or callback(null,result)
                        */
                    })
            })
        }], function (err, result) {
        // result is 'd'
        res.send (result)
    }
);

Apply this and you can see things you want in your final callback.