I have the following code. The array prices does not seem to be pushed to the prices
array despite successfully retrieving the ustock.unitprice
.
getLatestMarketPrices: function(username, callback) {
var prices = [];
db.find('portfolio', {user: username}, function(err, stocks) {
for(var i = 0; i < stocks.length; i++) {
module.exports.getQuote(stocks[i].stock, function(err, ustock) {
console.log(ustock.unitprice); // Retrieves 1.092
prices.push(ustock.unitprice); // Should push to prices array?
});
}
console.log(prices); // Prices is still [] despite earlier push.
callback(null, prices);
});
},
Is this a scoping issue? I'm not really sure why prices
is not pushed to.
Thanks very much.
If you know jquery, you could try deferred object
getLatestMarketPrices: function(username, callback) {
var prices = [];
var defer = $.Deferred();
//Attach a handler to be called when the deferred object is resolved
defer.done(function(){
console.log(prices);
callback(null, prices);
});
db.find('portfolio', {user: username}, function(err, stocks) {
for(var i = 0; i < stocks.length; i++) {
module.exports.getQuote(stocks[i].stock, function(err, ustock) {
console.log(ustock.unitprice); // Retrieves 1.092
prices.push(ustock.unitprice); // Should push to prices array?
//resolve when we retrieve all
if (prices.length == stocks.length){
defer.resolve();
}
});
}
});
},
Update: or don't need deferred object at all:
getLatestMarketPrices: function(username, callback) {
var prices = [];
db.find('portfolio', {user: username}, function(err, stocks) {
for(var i = 0; i < stocks.length; i++) {
module.exports.getQuote(stocks[i].stock, function(err, ustock) {
console.log(ustock.unitprice); // Retrieves 1.092
prices.push(ustock.unitprice); // Should push to prices array?
//callback only when we receive all
if (prices.length == stocks.length){
console.log(prices);
callback(null, prices);
}
});
}
});
},
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