Mongo occurance count by column - node.js

Question

I have a usecase to find the count of different statues like active, in-active, in-progress, etc,
the documents look like this -
{
"id": "1"
"status": "active"
},
{
"id": "2"
"status": "active"
},
{
"id": "3"
"status": "in-active"
},
{
"id": "4"
"status": "in-progress"
}
I needed output like -
{
"active": 2,
"in-active": 1,
"in-progress": 1
}
I am referring this answer but, not able to get the expected output -
Mongo count occurrences of each value for a set of documents
My code is as follows -
const mongoClient = require('mongodb').MongoClient;
const test = async () => {
const mongoUri = "mongodb://localhost:27017/";
const dbClientConnection = await mongoClient.connect(mongoUri, {
useNewUrlParser: true,
useUnifiedTopology: true
});
const db = await dbClientConnection.db("database name here");
const collection = await db.collection("collection name here");
let result = await collection.aggregate([
{
$group: {
_id: "$status",
sum: { $sum: 1 }
}
},
{
$group: {
_id: null,
status: {
$push: { k: "$_id", v: "$sum" }
}
}
},
{
$replaceRoot: {
newRoot: { $arrayToObject: "$status" }
}
}
])
console.log("result => ", result);
return result;
}
test();

Answer 1

The first stage is correct
$group by null and construct the array of key and value format
$arrayToObject convert above converted key-value pair array to an object
$replaceRoot to replace above object to root
let result = await collection.aggregate([
{
$group: {
_id: "$status",
sum: { $sum: 1 }
}
},
{
$group: {
_id: null,
status: {
$push: { k: "$_id", v: "$sum" }
}
}
},
{
$replaceRoot: {
newRoot: { $arrayToObject: "$status" }
}
}
])
Playground