How to slow down the code?

Question

Another problem... I have 2 functions :

function(data, callback){              //F1
            var URL = 'url';
            request(URL, function(err, response, body) {
                if(response.statusCode == 200){
                    var json = JSON.parse(body);
                    var chid = [];
                        for(var i = 0; i < json['champions'].length;i++){
                        chid.push(json['champions'][i].id);
                    }
                    data.rotation = chid;
                    free = chid;
                    callback(null, data);
            }

        });
    },
    function(data, callback) {        //f2
        for (var r=0; r<10; r++){
            var URL = 'url';
            request(URL,function(err, response, body) {
                if(response.statusCode == 200){
                    var json = JSON.parse(body);

                    x.push(json.name);
                    data.rot = x;
                }   
            })
        }
        callback(null, data);
    },

With F1 everything is ok. If I call console.log(free) or console.log(data.rotation) I got the array I want.

Function 2 is a bit problematic. Data is not avaible outside the for-loop. If I call console.log(data.rot) or console.log(x) outside the loop, it says it's undefined, so I can't get it with handlebars. I have no idea if it's all about the callback(null, data) position or about the for-loop. I can't handle it alone.

How to get access to data outside of the for-loop? Probably callback is being called faster than all requests are done. How to slow it down and make it working?

See [this answer](http://stackoverflow.com/questions/14220321/how-do-i-return-the-response-from-an-asynchronous-call/14220323#14220323) — peteb, Jul 11 '16 at 20:28

score 1 · Answer 1 · answered Jul 11 '16 at 20:30

1

To add some clarity to what Pointy said in comments, when the for loop executes the request, the inner function is called when the data returns. The for loop will complete, and then fire the callback, whether the data from the async request has returned or not, so the data will very likely not make it back before the callback gets called. In other words, it's a race condition that will almost always lose.

answered Jul 11 '16 at 20:30

nixkuroi

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So how to change the code to make it working? I'm not really good at this and it took me a few hours to build this up (and the function 2 is not working as i wanted) – BaSic Jul 11 '16 at 20:32
Does request have a parameter that can make it synchronous? – nixkuroi Jul 11 '16 at 20:38

score 0 · Accepted Answer · answered Jul 12 '16 at 08:29

X was defined above. This code is working well.

function(data, callback) {        //f2
for (var r=0, dataRx=0; r<10; r++){
    var URL = 'url';
    request(URL,function(err, response, body) {
        if(response.statusCode == 200){
            var json = JSON.parse(body);

            x.push(json.name);
            data.rot = x;
        }
        dataRx++;
        if(dataRx === 10) callback(null, data);
    })
}

},

How to slow down the code?

2 Answers2