Using Express.js's res.send() with async.each - express

Question

async1.each(arr, function(arrayMember) {
orders.where('name', arrayMember).fetch({withRelated: ['allOrders']}).
then(function(dd2, callback) {
dd2 = dd2.toJSON();
var sendMemberOrder = {};
sendMemberOrder.name = dd2.name;
sendMemberOrder.lastOrder = dd2.allOrders.length;
res.send(sendMemberOrder);
});
}, function(err) {
if (err) {
console.log("err");
}
});
I'm trying to use Express's res.send() feature but given that I'm using async.each, I'm getting
headers already sent
error.
How can I pass the result of each iteration as an array when a request is being made?

Answer 1

Since you already use promises here, I would like to doscourage you from using async.js here. Your code is broken anyway as it does not call callback at all, and the callback parameter is declared on the wrong function. Instead you could try this:
app.get(your_route, function(req, res, next) {
// obtain arr
Promise.all(arr.map(function(arrayMember) {
return orders.where('name', arrayMember)
.fetch({withRelated: ['allOrders']})
.then(function(dd2) {
dd2 = dd2.toJSON();
return {
name: dd2.name,
lastOrder: dd2.allOrders.length
};
});
})).then(function(resultData) {
res.send(resultData);
}).catch(function(err) {
console.log(err);
next(err);
});
});