Get specific data from a JSON object (Steam Api) - json

Question

So I am practising some nodejs and this time I am playing around with steam api and json objects. But I am having some problems.
So, from the Steam api,
http://steamcommunity.com/profiles/<steamid>/inventory/json/730/2
I got the json from this code,
var request = require('request');
var url = "http://steamcommunity.com/profiles/<steamid>/inventory/json/730/2"
request({
url: url,
json: true
}, function (error, response, body) {
if (!error && response.statusCode === 200) {
var json = JSON.parse(body);
console.log(body)
}
});
And the json looks lite this, json-link
From the json I want to take out the classid and instanceid from each of the items, but there comes the problem. I don't know how. I know I need to parse it but nothing more unfortunately.
Would be very helpful if someone could explain how, or link a guide/tutorial so I can learn.
Thanks!
EDIT:
var request = require('request');
var _ = require('lodash');
var url = "http://steamcommunity.com/profiles/76561198007691048/inventory/json/730/2";
request({
url: url,
json: true
}, function jsonParse(error, response, data) {
console.log(data.rgDescriptions);
var item = getItems(data.rgDescriptions);
console.log(item);
}
);
function getItems(data){
var item = data;
if(!item){
return "error";
}
return _(item).keys().map(function(id){
return _.pick([id], "name");}).value();
Console give me this; [ {}, {}, {}, {}, {}, {}, {}, {},
{},.... ]
JSON look like this;
'1293508920_0':
{ appid: '730',
classid: '1293508920',
instanceid: '0',
icon_url: '-9a81dlWLwJ2UUGcVs_nsVtzdOEdtWwKGZZLQHTxDZ7I56KU0Zwwo4NUX4oFJZEHLbXU5A1PIYQNqhpOSV-fRPasw8rsUFJ5KBFZv668FF4u1qubIW4Su4mzxYHbzqGtZ-KGlz8EuJcg3rnE9NiijVe3_UY-Zzr2JJjVLFEEeiQRtg',
icon_drag_url: '',
name: 'Shadow Case',
market_hash_name: 'Shadow Case',
market_name: 'Shadow Case',
name_color: 'D2D2D2',
background_color: '',
type: 'Base Grade Container',
tradable: 1,
marketable: 1,
commodity: 1,
market_tradable_restriction: '7',
},
'1644880589_236997301':
{ appid: '730',
classid: '1644880589',
instanceid: '236997301',
icon_url: '-9a81dlWLwJ2UUGcVs_nsVtzdOEdtWwKGZZLQHTxDZ7I56KU0Zwwo4NUX4oFJZEHLbXU5A1PIYQNqhpOSV-fRPasw8rsUFJ4MAlVo6n3e1Y27OPafjBN09izq42ChfbzNvXTlGkD6p0lj7_FpNjx0VDj_UBoZ272cNfBdg48MAyB-VS3xum61Me_ot2XnqkB5QYc',
icon_drag_url: '',
name: 'MLG Columbus 2016 Mirage Souvenir Package',
market_hash_name: 'MLG Columbus 2016 Mirage Souvenir Package',
market_name: 'MLG Columbus 2016 Mirage Souvenir Package',
name_color: 'D2D2D2',
background_color: '',
type: 'Base Grade Container',
tradable: 1,
marketable: 1,
commodity: 0,
market_tradable_restriction: '7',
},

Answer 1

To work with complex objects or collections you can use lodash library.
So, you have json with the following format:
{
"success":true,
"rgInventory": {
"5719625206": {"id":"5719625206","classid":"1651313004","instanceid":"188530139","amount":"1","pos":1},
"5719034454": {"id":"5719034454","classid":"1649582636","instanceid":"188530139","amount":"1","pos":2},
"5718628709": {"id":"5718628709","classid":"1649582636","instanceid":"188530139","amount":"1","pos":3},
...
}
}
To extract array of required items, first of all install lodash library in your project: npm i -S, after that add this code into your file:
var _ = require('lodash');
function extractItems(data) {
var rgInventory = _.get(data, 'rgInventory');
if (!rgInventory) {
return [];
}
return _(rgInventory)
.keys()
.map(function(id) {
return _.pick(rgInventory[id], ['classid', 'instanceid']);
})
.value();
}