Docs Menu

Quick Start

On this page

  • Set up Your Project
  • Initialize with Go Mod
  • Add MongoDB as a Dependency
  • Create a MongoDB Cluster
  • Set up a Free Tier Cluster in Atlas
  • Query Your MongoDB Cluster from Your Application
  • Next steps

This guide shows you how to create an application that uses the Go driver to connect to a MongoDB Atlas cluster. If you prefer to connect to MongoDB using a different driver or programming language, see our list of official MongoDB drivers.

The Go driver lets you connect to and communicate with MongoDB clusters from a Go application.

MongoDB Atlas is a fully-managed cloud database service that hosts your data on MongoDB clusters. In this guide, we show you how to get started with your own free (no credit card required) cluster.

Follow the steps below to connect your Go application with a MongoDB Atlas cluster.

Create a new directory and initialize your project with go mod.

mkdir go-quickstart
cd go-quickstart
go mod init go-quickstart

Use go get to add the Go driver as a dependency.

go get go.mongodb.org/mongo-driver/mongo

After setting up your Go project dependencies, create a MongoDB cluster where you can store and manage your data. Complete the Get Started with Atlas guide to set up a new Atlas account, free tier MongoDB cluster, load datasets, and interact with the data.

After completing the steps in the Atlas guide, you should have a new MongoDB cluster deployed in Atlas, a new database user, and sample datasets loaded into your cluster.

In this step, you create and run an application that uses the Go driver to connect to your MongoDB cluster and run a query on the sample data.

You pass instructions to the driver on where and how to connect to your MongoDB cluster in a string called the connection string. This string includes information on the hostname or IP address and port of your cluster, authentication mechanism, user credentials when applicable, and other connection options.

To retrieve your connection string for the cluster and user you created in the previous step, log into your Atlas account and navigate to the Clusters section and click the Connect button for the cluster that you want to connect to as shown below.

Atlas Connection GUI cluster selection screen

Proceed to the Connect Your Application step and select the Go driver. Then, click the Copy button to copy the connection string to your clipboard as shown below.

Atlas Connection GUI connection string screen

Save your Atlas connection string in a safe location that you can access for the next step.

Next, create a file to contain your application called main.go in the base directory of your project. Use the following sample code to run a query on your sample dataset in MongoDB Atlas.

Set the value of the uri variable with your MongoDB Atlas connection string, or create an environmental variable with the name MONGODB_URI with your Atlas connection string.

export MONGODB_URI='<your atlas connection string>'
Note

Make sure to replace the "<password>" section of the connection string with the password you created for your user that has atlasAdmin permissions.

package main
import (
"context"
"encoding/json"
"fmt"
"log"
"os"
"github.com/joho/godotenv"
"go.mongodb.org/mongo-driver/bson"
"go.mongodb.org/mongo-driver/mongo"
"go.mongodb.org/mongo-driver/mongo/options"
)
func main() {
if err := godotenv.Load(); err != nil {
log.Println("No .env file found")
}
uri := os.Getenv("MONGODB_URI")
if uri == "" {
log.Fatal("You must set your 'MONGODB_URI' environmental variable. See\n\t https://docs.mongodb.com/drivers/go/current/usage-examples/#environment-variable")
}
client, err := mongo.Connect(context.TODO(), options.Client().ApplyURI(uri))
if err != nil {
panic(err)
}
defer func() {
if err := client.Disconnect(context.TODO()); err != nil {
panic(err)
}
}()
coll := client.Database("sample_mflix").Collection("movies")
title := "Back to the Future"
var result bson.M
err = coll.FindOne(context.TODO(), bson.D{{"title", title}}).Decode(&result)
if err == mongo.ErrNoDocuments {
fmt.Printf("No document was found with the title %s\n", title)
return
}
if err != nil {
panic(err)
}
jsonData, err := json.MarshalIndent(result, "", " ")
if err != nil {
panic(err)
}
fmt.Printf("%s\n", jsonData)
}

Run the sample code with the following command from your command line:

go run main.go

When you run main.go, it should output the details of the movie from the sample dataset which looks something like the following:

{
"_id": "573a1398f29313caabce9682",
...
"title": "Back to the Future",
...
}

If you receive no output or an error, check whether you properly set up your environment variable and whether you loaded the sample dataset in your MongoDB Atlas cluster.

Tip

If your output is empty, ensure you have loaded the sample datasets into your cluster.

After completing this step, you should have a working application that uses the Go driver to connect to your MongoDB cluster, run a query on the sample data, and print out the result.

Learn how to read and modify data using the Go driver in our Fundamentals CRUD guide or how to perform common operations from our Usage Examples.

Give Feedback
© 2021 MongoDB, Inc.

About

  • Careers
  • Legal Notices
  • Privacy Notices
  • Security Information
  • Trust Center
© 2021 MongoDB, Inc.