Javascript 计算mongodb中对象的总值

这是我查找总值的查询。我使用$project

{
        "id" : "12345"
        "energy" : "electricity",
        "type" : "lighting",
        "value" : 24324
    }, 
    {
        "id" : "12345"
        "energy" : "electricity",
        "type" : "equipment",
        "value" : 24324
    }, 
    {
        "energy" : "electricity",
        "type" : "fans",
        "value" : 24324
    }, 
    {
        "id" : "12345"
        "energy" : "electricity",
        "type" : "distribution",
        "value" : 24324
    }, 
    {
        "id" : "12345"
        "energy" : "electricity",
        "type" : "chiller",
        "value" : 24324
    }, 
    {
       "id" : "12345"
        "energy" : "electricity",
        "type" : "other",
        "value" : 24324
    }

---

我试图找到总价值。请任何人帮忙找出总价值。还可以使用Id-wise查找值。

db.products.aggregate（[{$group:{{{{u Id:'$type'，total:{$sum:'$value'}}}}}]）谢谢@Joel Garcia Nuño，但是我如何找到Id:“12345”尝试在{u Id:'中过滤的总数，它将等于12345 Id，但其中一个没有，您可能需要检查它是否为null，不要做任何事情

  db.invoices.aggregate([
    {
    $project: {
        total: {$sum : "$value"}
    }
}])