Поиск через JSON для ключа

//return an array of values that match on a certain key
function getValues(obj, key) {
    var objects = [];
    for (var i in obj) {
        if (!obj.hasOwnProperty(i)) continue;
        if (typeof obj[i] == 'object') {
            objects = objects.concat(getValues(obj[i], key));
        } else if (i == key) {
            objects.push(obj[i]);
        }
    }
    return objects;
}
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