Question

Sorry if this question is simple but I have been using node.js for only a few days.

Basically i receive a json with some entries. I loop on these entries and launch a http request for each of them. Something like this:

for (var i in entries) {
    // Lots of stuff

    http.get(options, function(res) {
        // Parse reponse and detect if it was successfully
    });
}

How can i detect when all requests were done? I need this in order to call response.end().

Also i will need to inform if each entry had success or not. Should i use a global variable to save the result of each entry?

Answer 1

You can e.g. use caolans “async” library:

async.map(entries, function(entry, cb) {
  http.get(options, function(res) {
    // call cb here, first argument is the error or null, second one is the result
  })
}, function(err, res) {
  // this gets called when all requests are complete
  // res is an array with the results
}