package main

import (
    "context"
    "fmt"
    "time"

    "go.mongodb.org/mongo-driver/bson"
    "go.mongodb.org/mongo-driver/mongo"
    "go.mongodb.org/mongo-driver/mongo/options"
)

func main() {
    client, err := mongo.NewClient(options.Client().ApplyURI("mongodb://root:XXX@metis:53929/?connect=direct"))
    if err != nil {
        panic(err)
    }
    ctx, cancel := context.WithTimeout(context.Background(), 20*time.Second)
    defer cancel()
    err = client.Connect(ctx)
    if err != nil {
        panic(err)
    }

    admin := client.Database("admin")
    res := admin.RunCommand(context.Background(), bson.D{{"listDatabases", 1}})
    if res.Err() != nil {
        panic(res.Err())
    }
    var doc bson.D
    if err := res.Decode(&doc); err != nil {
        panic(err)
    }
    json, err := bson.MarshalExtJSON(doc, false, false)
    if err != nil {
        panic(err)
    }
    fmt.Println(string(json))
}