Retrieve only matched object from nested array in mongodb - mongodb

Question

In this json , I need a find query which finds all the field where the "status":"Y", if the parent field has "status":"N", ignore the child field , else find the child field where the "status":"Y" along with its parent field
Note: The sub field is in a array
[
{
"type": "Type 1",
"status": "Y",
"code": "1",
"category": [
{
"type": "Cat 1",
"status": "Y",
"code": "1000",
"subcategories": [
{
"type": "Sub 1",
"status": "N",
"code": "1001"
},
{
"type": "Sub 2",
"status": "N",
"code": "1002"
},
{
"type": "Sub 3",
"status": "Y",
"code": "1003"
}
]
},
{
"type": "Cat 2",
"status": "N",
"code": "2000",
"subcategories": [
{
"type": "Sub 4",
"status": "Y",
"code": "2001"
},
{
"type": "Sub 5",
"status": "Y",
"code": "2002"
}
]
}
]
}
]
My Output Should be like this
[
{
"type": "Type 1",
"status": "Y",
"code": "1",
"category": [
{
"type": "Cat 1",
"status": "Y",
"code": "1000",
"subcategories": [
{
"type": "Sub 3",
"status": "Y",
"code": "1003"
}
]
} ]
}
]
Thanks in Advance:)

Answer 1

You can try below aggregation
db.collection.aggregate([
{ "$match": { "status": "Y" }},
{ "$unwind": "$category" },
{ "$match": { "category.status": "Y" } },
{ "$project": { "type": 1, "status": 1, "code": 1,
"category.type": "$category.type",
"category.status": "$category.status",
"category.code": "$category.code",
"category.subcategories": {
"$filter": {
"input": "$category.subcategories",
"as": "subcategory",
"cond": {
"$eq": [
"$$subcategory.status",
"Y"
]
}
}
}
}},
{ "$group": {
"_id": "$_id",
"type": { "$first": "$type" },
"status": { "$first": "$status" },
"code": { "$first": "$code" },
"category": { "$push": "$category" }
}}
]).then((data) => {
res.send(data)
})
Gives you following output (check here)
[
{
"_id": ObjectId("5a934e000102030405000000"),
"category": [
{
"code": "1000",
"status": "Y",
"subcategories": [
{
"code": "1003",
"status": "Y",
"type": "Sub 3"
}
],
"type": "Cat 1"
}
],
"code": "1",
"status": "Y",
"type": "Type 1"
}
]