Node Exports Function Returning Undefined - json

Question

I have a an exports function I'm calling that should return a json array of draft results. In the route below in app.js, when I console.log draft_results, I get undefined
app.get('/draft-results', function(req, res) {
var draft_results = fantasy.getDraftResults(req, res);
console.log(util.inspect(draft_results, false, null));
//looks in views folder by default
res.render('draft-results', {
draft_results: draft_results
});
});
In my other file, this is the function that should be returning the json array. If i console.log draft, the data is there.
exports.getDraftResults = function(req, res, cb) {
oauth.get(
"http://fantasysports.yahooapis.com/fantasy/v2/league/" + conf.LEAGUE_ID + "/draftresults?format=json",
req.user.accessToken,
req.user.tokenSecret,
function(e, data, resp) {
if (e) console.error(e);
data = JSON.parse(data);
var draft = data.fantasy_content.league[1].draft_results;
res.json(draft);
}
);
};
I feel like I am returning the data incorrectly, and I can't seem to find any other good examples out there. Could someone please assist?

Answer 1

getDraftResults() is asynchronous. That means the results it generates occur sometime later. Thus, it cannot return its results directly from the function like you are trying to use.
It is unclear what you want to be doing here. Inside of getDraftResults() you are creating a JSON response back to the web request that started all this. That, in itself would be fine and will work as you have it (except the error handling is missing).
But, in your app.get() handler, you have completely different code that seems to thing that getDraftResults() is going to return a value (it has no return value at all) and then you will later use that return value.
So, if you just want getDraftResults to make a JSON response to the original web request, it's already doing that and you can remove the rest of what you have in the app.get() handler. If that's not really what you want to do and you want to use the response from getDraftResults() inside of the app.get() handler, then you will have to change the design of both functions and likely pass a callback to getDraftResults() so the callback can supply the asynchronous response and you can then continue the rest of the app.get() functionality in that callback.
If you're trying to do the latter, then here's a scaffolding (I don't know exactly what you're trying to accomplish so I can't be too detailed here):
app.get('/draft-results', function(req, res) {
fantasy.getDraftResults(req, function(err, draft_results) {
if (err) {
// send some sort of error response here
console.error(err);
return;
}
console.log(util.inspect(draft_results, false, null));
//looks in views folder by default
res.render('draft-results', {
draft_results: draft_results
});
});
});
exports.getDraftResults = function(req, cb) {
oauth.get(
"http://fantasysports.yahooapis.com/fantasy/v2/league/" + conf.LEAGUE_ID + "/draftresults?format=json",
req.user.accessToken,
req.user.tokenSecret,
function(e, data, resp) {
if (e) {
console.error(e);
cb(e);
return;
}
data = JSON.parse(data);
var draft = data.fantasy_content.league[1].draft_results;
// send results back to caller
cb(null, draft);
}
);
};