how to connect with mongodb in go using atlas?

I am getting a server selection timeout while connecting to mongodb.Any help is appreciated.

> selection error: server selection timeout, current topology: { Type:
> ReplicaSetNoPrimary, Servers: [{ Addr:
> ac-pjyudwq-shard-00-01.1bnb2bm.mongodb.net:27017, Type: Unknown, Last
> error: dial tcp 3.6.207.111:27017: i/o timeout }, { Addr:
> ac-pjyudwq-shard-00-00.1bnb2bm.mongodb.net:27017, Type: Unknown, Last
> error: dial tcp 3.7.150.83:27017: i/o timeout }, { Addr:
> ac-pjyudwq-shard-00-02.1bnb2bm.mongodb.net:27017, Type: Unknown, Last
> error: dial tcp 3.7.137.42:27017: i/o timeout }, ] } exit status 1

Code that I used for the connection

const MONGOURL = "mongodb+srv://sai:sai@cluster0.1bnb2bm.mongodb.net/?retryWrites=true&w=majority"

var collection *mongo.Collection

func init() {
    fmt.Println("in the init function") var databasename string = "GOAPI"
    var collectionname string = "Movies"
    client, err: = mongo.Connect(context.TODO(), options.Client().ApplyURI(MONGOURL)) if err != nil {
        fmt.Println("unable to get mongo connection ") log.Fatal(err)
    }
    collection = ( * mongo.Collection)(client.Database(databasename).Collection(collectionname)) fmt.Println("sucessfully collection is created ") doc: = Movie {
        Name: "rrr",
        Watched: false,
        Rating: 9,
        Id: "12121"
    }
    result, err: = collection.InsertOne(context.Background(), doc) if err != nil {
        log.Fatal("hey unable to insert one ", err)
    }
    fmt.Println("sucessfully added : ", result.InsertedID)

    // mongo.Connect()`your text`
}

I am hosting my test Atlas cluster on AWS so I wanted to have similar credential management to the AWS process. From the AWS credentials page:

The default provider chain looks for credentials in the following order:

1. Environment variables.
2. Shared credentials file.
3. If your application is running on an Amazon EC2 instance, IAM role for Amazon EC2.

Therefore, I wanted to implement the environment veriable for my simple login to Atlas example. Code below assumes that the following line has been issued at the command line

export MONGO_PW='<your Atlas admin user password>'

Then the following program will verify your connection

package main

import (
    "context"
    "fmt"
    "os"

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

var username = "<username>"
var host1 = "<atlas host>"  // of the form foo.mongodb.net

func main() {

    ctx := context.TODO()

    pw, ok := os.LookupEnv("MONGO_PW")
    if !ok {
        fmt.Println("error: unable to find MONGO_PW in the environment")
        os.Exit(1)
    }
    mongoURI := fmt.Sprintf("mongodb+srv://%s:%s@%s", username, pw, host1)
    fmt.Println("connection string is:", mongoURI)

    // Set client options and connect
    clientOptions := options.Client().ApplyURI(mongoURI)
    client, err := mongo.Connect(ctx, clientOptions)
    if err != nil {
        fmt.Println(err)
        os.Exit(1)
    }

    err = client.Ping(ctx, nil)
    if err != nil {
        fmt.Println(err)
        os.Exit(1)
    }

    fmt.Println("Connected to MongoDB!")
}

From here the rest of the tutorial linked in my original question goes smoothly.