For loop with promises

Question

I'm running a for loop which calls a function that does a GET request

for (var i = 0; i < uids.length; i++) {

makeRequest(uids[i]);

}

function makeRequest(hostname) {

  request({
    url: url,
    json: true
    }, function(error, response, body) {
    if (!error && response.statusCode === 200) {
    //display the data etc
    }
    }

}

Is it possible for the for loop to ONLY iterate after each request is made and completed. eg once the GET request is complete and returns a result?

I thought about implementing some timeouts, however I am not sure that that is the best solution for this.

Answer 1

Make it recursive until you have items left:

var itemsLeft = uids.length;

function makeRequest(hostname) {
   request({
      url: url,
      json: true
   }, function(error, response, body) {
     if (!error && response.statusCode === 200) {
        if( itemsLeft !== 0 ) { 
           makeRequest( hostname );
           itemsLeft -= 1;
        } 
     }
   })
}

Answer 2

Can suggest to take a look into something like https://github.com/FuturesJS/forEachAsync . Check their example to understand how to use the library.