I'm trying to create function that can parse JSON from a url. Here's what I have so far:

function get_json(url) {
    http.get(url, function(res) {
        var body = '';
        res.on('data', function(chunk) {
            body += chunk;
        });

        res.on('end', function() {
            var response = JSON.parse(body);
                return response;
        });
    });
}

var mydata = get_json(...)

When I call this function I get errors. How can I return parsed JSON from this function?

Your return response; won't be of any use. You can pass a function as an argument to get_json, and have it receive the result. Then in place of return response;, invoke the function. So if the parameter is named callback, you'd do callback(response);.

// ----receive function----v
function get_json(url, callback) {
    http.get(url, function(res) {
        var body = '';
        res.on('data', function(chunk) {
            body += chunk;
        });

        res.on('end', function() {
            var response = JSON.parse(body);
// call function ----v
            callback(response);
        });
    });
}

         // -----------the url---v         ------------the callback---v
var mydata = get_json("http://webapp.armadealo.com/home.json", function (resp) {
    console.log(resp);
});

Passing functions around as callbacks is essential to understand when using NodeJS.

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