MongoDB nested array aggregation correctly - node.js

Question

Ok so i've tired many things to solve this issue, what im facing with is, i have this document
{
"_id": "5ef9c6a9691c33e13c455413",
"tags": [
"chicken wings",
"pizza",
"burgers"
],
"shopName": "Emily",
"isOpen": true,
"address": "919 Fulton St, Brooklyn, NY 11238",
"image": "random-2.jpg",
"category": "Asian",
"stars": [
12,
22,
32,
0,
0
],
"logo": "logo.png",
"phone": "[phone]",
"totalCompletedOrders": 22,
"eta": "60",
"products": [
{
...
"category": "Appeteasers"
},
{
...
"category": "Appeteasers"
},
{
...
"category": "Appeteasers"
},
{
...
"category": "Appeteasers"
},
{
...
"category": "Appeteasers"
},
{
...
"category": "Appeteasers"
},
{
...
"category": "Appeteasers"
},
{
...
"category": "Fino sides"
},
{
...
"category": "Fino sides"
},
{
...
"category": "Fino sides"
},
{
...
"category": "Fino sides"
},
{
...
"category": "Peri-peri chicken"
},
{
...
"category": "Peri-peri chicken"
},
{
...
"category": "Peri-peri chicken"
},
{
...
"category": "Peri-peri chicken"
},
{
...
"category": "Peri-peri chicken"
},
{
...
"category": "Peri-peri chicken"
},
{
...
"category": "Peri-peri chicken"
},
{
...
"category": "Peri-peri chicken"
},
{
...
"category": "Peri-peri chicken"
},
{
...
"category": "Peri-peri chicken"
},
{
...
"category": "Peri-peri chicken"
},
{
...
"category": "Peri-peri chicken"
},
{
...
"category": "Peri-peri chicken"
},
{
...
"category": "Peri-peri chicken"
},
{
...
"category": "Peri-peri chicken"
},
{
...
"category": "Peri-peri chicken"
},
{
...
"category": "Peri-peri chicken"
}
]
}
so my issue is i need to group the products array and make it look into something like this or close to it
{
"_id": "5ef9c6a9691c33e13c455413",
"tags": [
"chicken wings",
"pizza",
"burgers"
],
"shopName": "Emily",
"isOpen": true,
"address": "919 Fulton St, Brooklyn, NY 11238",
"image": "random-2.jpg",
"category": "Asian",
"stars": [
12,
22,
32,
0,
0
],
"logo": "logo.png",
"phone": "[phone]",
"totalCompletedOrders": 22,
"eta": "60",
"products": [{
category: "Appeteasers",
products:[...all Appeteasers chicken here]
},{
category: "Fino sides chicken",
products:[...all Fino sides chicken here]
},{
category: "Peri-peri chicken",
products:[...all Peri-peri chicken here]
}]
}
what i've tired is
Store.aggregate([
{$match:{ _id: id}, },
{ $unwind: "$products" },
{
$group : {
_id: "$products.category",
"products" : {"$addToSet": "$products"},
}
},
]);
and i got so close to the result but i the root fields are not included
[
{
"_id": "Peri-peri chicken",
"products": [...]
},
{
"_id": "Appeteasers",
"products": [...]
},
{
"_id": "Fino sides",
"products": [...]
}
]
would love some help, thank you

Answer 1

To get all other keys in the document you have mention the key in $project, then only they will be accessible. In below code, I have just added three of them to show how it has to be done. You can add rest of them.
Store.aggregate([
{
$match:{ _id: id}
},
{
$project: { products: "$products", shopName: "$shopName", stars: "$stars", tags: "$tags", }
},
{
$unwind: "$products"
},
{
$group : {
_id: "$products.category",
"products" : {"$addToSet": "$products"},
"tags": {"$addToSet": "$tags"},
"stars": {"$addToSet": "$stars"},
"shopName": {"$first": "$shopName"}
}
},
{
$project: {products: "$products", tags: "$tags", shopName: "$shopName", stars: "$stars" }
},
]);