You could do something like this with ECMA5. This performs, generically, the sort
and reduce
that you have indicated in your question, so you can add more fields to your data without having to change the routine. It also leaves your original data intact.
Javascript
var original = {
'res': [{
'type': 'stream',
'price': '3.99',
'id': '13nee'
}, {
'type': 'stream',
'price': '2.99',
'id': '8ejwj'
}, {
'type': 'buy',
'price': '3.99',
'id': '9akwk'
}]
},
sorted = {};
original.res.slice().sort(function (a, b) {
a = +(a.price);
b = +(b.price);
if (a < b) {
return -1;
}
if (a > b) {
return 1;
}
return 0;
}).reduce(function (acc, element) {
if (!acc[element.type]) {
acc[element.type] = [];
}
acc[element.type].push(Object.keys(element).filter(function (name) {
return name !== 'type';
}).reduce(function (prev, name) {
prev[name] = element[name];
return prev;
}, {}));
return acc;
}, sorted);
console.log(JSON.stringify(sorted));
Output
{
"stream": [{
"price": "2.99",
"id": "8ejwj"
}, {
"price": "3.99",
"id": "13nee"
}],
"buy": [{
"price": "3.99",
"id": "9akwk"
}]
}
On jsFiddle