Async parallel requests are running sequentially

Question

I am running a server using Node.js and need to request data from another server that I am running (localhost:3001). I need to make many requests (~200) to the

Answer 1

Sounds like you're just trying to download a bunch of URLs in parallel. This will do that:

var request = require('request');
var async = require('async');

var urls = ['http://microsoft.com', 'http://yahoo.com', 'http://google.com', 'http://amazon.com'];

var loaders = urls.map( function(url) {
  return function(callback) {
        request(url, callback);
  }
});

async.parallel(loaders, function(err, results) {
        if (err) throw(err); // ... handle appropriately
        // results will be an array of the results, in 
        // the same order as 'urls', even thought the operation
        // was done in parallel
        console.log(results.length); // == urls.length
});

or even simpler, using async.map:

var request = require('request');
var async = require('async');

var urls = ['http://microsoft.com', 'http://yahoo.com', 'http://google.com', 'http://amazon.com'];

async.map(urls, request, function(err, results) {
        if (err) throw(err);          // handle error 
        console.log(results.length);  // == urls.length
});