如何在Kotlin/JS中编写MongoDB聚合

import org.litote.kmongo.*
import com.mongodb.ConnectionString

fun main() {
    val connectionString = ConnectionString("mongodb://localhost:27017")
    val client = KMongo.createClient(connectionString)
    val database = client.getDatabase("mydb")
}

import org.bson.Document

fun main() {
    // ...

    val collection = database.getCollection("mycollection")

    val pipeline = listOf(
        Document("\$match", Document("status", "active")),
        Document("\$group", Document("_id", "\$category", "count", Document("\$sum", 1))),
        Document("\$sort", Document("count", -1))
    )

    val result = collection.aggregate(pipeline)

    for (document in result) {
        println(document)
    }
}