Set up the Task Tracker Tutorial Backend¶

Overview¶

Before we can implement any client SDK functionality for the Task Tracker, we need to create a backend Realm app to serve SDK requests like authentication and Realm Sync. To make this easier and faster, we've already prepared a backend Realm app configuration for you, complete with functions, triggers, a schema, and the Realm Sync configuration you'll need to connect with one of our front-end tutorial apps.

To use our pre-made backend, you'll have to:

1. Create an Atlas account, if you don't already have one. (3 minutes)
2. Create a free Atlas cluster running MongoDB 4.4 or higher. (5 minutes)
3. Install the Realm CLI. (5 minutes)
4. Add a programmatic API key to your Atlas project and use it to log into the Realm CLI. (5 minutes)
5. Use the Realm CLI to create a new Task Tracker backend Realm app with our pre-made Task Tracker backend. (5 minutes)

Once we've finished these steps, we can start writing code to implement a frontend using Swift, Kotlin, or JavaScript.

A. Create an Atlas Account¶

Time estimate: 3 minutes

To begin, you'll need a MongoDB Atlas account. If you've already got an existing MongoDB Atlas Account, you can proceed to the next step. If you don't have an Atlas account, follow the steps below to create one:

1. Navigate to the MongoDB Atlas login page.

1. Click Login.
2. Either enter a new set of user credentials or click the Sign Up with Google button.
3. Click Sign Up to create your account.

4. Follow the prompts to create an organization and project in your Atlas account. You can use the default suggested names or enter your own.

   

When you finish creating your organization and project, you should end up on a screen that prompts you to create an Atlas cluster:

B. Create a Free Atlas Cluster¶

Time estimate: 5 minutes

Next, you'll need an MongoDB Atlas cluster running MongoDB 4.4 or higher. If you've already created a free cluster in your Atlas project running a version of MongoDB lower than 4.4, you can create a new project in Atlas and then create a new cluster running MongoDB 4.4 or higher in that project using the instructions below. If you haven't created any clusters yet, follow the instructions below to create your first free cluster:

1. Log into your MongoDB Atlas account at cloud.mongodb.com.

2. Once you're logged into your account, Atlas should prompt you to create your first cluster. In the Shared Clusters category, click Create a Cluster. Alternatively, you can click Build a Cluster from the project view in your Atlas account.

   
3. Under Cloud Provider & Region, select AWS and N. Virginia (us-east-1).
4. Under Additional Settings, select MongoDB 4.4 (or a higher version) from the Select a Version dropdown.
5. Under Cluster Name, enter the name Cluster0 for your new cluster.
6. Click the Create Cluster button at the bottom of the page.

After creating your cluster, Atlas should launch the project view for your Atlas account. In this view, you'll see Atlas's progress as it initializes your new cluster:

C. Install the Realm CLI¶

Time estimate: 5 minutes

Now that you've created a cluster to use as the data source for your Realm app, we need some way to create the app itself. In most cases you'd use the Realm UI, which you can access through the Atlas UI. However, for the purposes of this tutorial, we're going to use the Realm Command Line Interface, also known as realm-cli.

We're using the Realm CLI because realm-cli allows you to manage your Realm apps programmatically using JSON configuration files instead of the Realm UI. This lets you get started with a pre-prepared app configuration faster. Follow the instructions below to install the Realm CLI in your development environment using either a package manager or the realm-cli binary:

Realm CLI is available on npm. To install it on your system, ensure that you have Node.js installed and then run the following command in your shell:

npm install -g mongodb-realm-cli

realm-cli --version

D. Add an API Key to Your Atlas Project & Log into the Realm CLI¶

Time estimate: 5 minutes

Now that you've got realm-cli installed to your development environment, you'll need a way to authenticate using realm-cli. For security reasons, realm-cli only allows login using a programmatic API key, so we'll begin by creating a programmatic API Key that you can use to administrate your new Atlas project:

1. Click Access Manager at the top of the Atlas UI. Select the Project Access option from the dropdown.
2. Navigate to the API Keys tab.
3. Click the Create API Key button.

4. In the Description text box, enter "API Key for the MongoDB Realm CLI".

   

5. In the Project Permissions dropdown, select "Project Owner" and deselect "Project Read Only".

   
6. Click Next.
7. Copy your Public API Key and save it somewhere.
8. Copy your Private API Key and save it somewhere; after leaving this page, you will no longer be able to view it via the Realm UI.
9. Click the Add Access List Entry button.
10. Click Use Current IP Address.
11. Click Save.
12. When you have safely recorded your private API key, click Done to navigate back to the Project Access Manager page.

13. Use the following command in your terminal to authenticate with the Realm CLI:

    realm-cli login --api-key <public API key> --private-api-key <private API key>

If realm-cli produces output like the following, you have successfully authenticated:

Successfully logged in

E. Use the Realm CLI to Create a New Task Tracker Backend Realm App¶

Time estimate: 5 minutes

Now that you've got an Atlas account, an Atlas cluster running MongoDB 4.4 or higher, and an authenticated realm-cli session, you're ready to fetch the Task Tracker backend configuration. Begin by downloading the realm-tutorial-backend github repository using the git command line tool:

1. Run the following command to download the pre-made Task Tracker backend configuration:

   git clone https://github.com/mongodb-university/realm-tutorial-backend.git

   You should see output like the following:

   Cloning into 'realm-tutorial-backend'...
   remote: Enumerating objects: 39, done.
   remote: Counting objects: 100% (39/39), done.
   remote: Compressing objects: 100% (31/31), done.
   remote: Total 39 (delta 3), reused 39 (delta 3), pack-reused 0
   Receiving objects: 100% (39/39), 7.25 KiB | 1.81 MiB/s, done.
   Resolving deltas: 100% (3/3), done.

   The directory where you ran the above git clone command should now contain another directory called realm-tutorial-backend. We'll use the contents of that directory to create your very own Task Tracker Realm app backend with the Realm CLI.

   Important

   Realm CLI Version Compatibility

   If you're using version 1 of realm-cli then you will need to use a different branch that contains compatible configuration files:

   git checkout -b final-v1 origin/final-v1

2. Navigate into the root directory of the realm-tutorial-backend project:

   cd realm-tutorial-backend

3. Run the push command of realm-cli to create your app.

   realm-cli push

4. realm-cli may take a few seconds to query your Atlas project, but you should soon see the following output:

   Do you wish to create a new app? [y/n]

   Press "y", then press ENTER to confirm your intention to create a new app.

5. realm-cli will prompt you for the following details:

   App name [tasktracker]:
   App Location
   App Deployment Model
   App Environment

   Press ENTER at each prompt to use the default value for your app configuration.

6. Press "y", then press ENTER to confirm the values for the app configuration

You should see the following output if your push command successfully created a new app:

Successfully pushed app up

You can confirm that your app was created successfully by navigating to the Realm tab in the Atlas UI. You should see a Realm app named tasktracker:

F. Verify that the Task Tracker Backend is Properly Configured¶

Time estimate: 5 minutes

Now that you've successfully created your application, it's time to explore the provided configuration. You can access your app by navigating to the Realm tab in the Atlas UI. Click on the card representing the tasktracker app to launch the Realm UI for managing the Task Tracker backend.

Now that we can view the configuration of our app in the Realm UI, we can take a look at all of the configuration uploaded from the JSON in realm-tutorial-backend. If you'd rather jump straight into a client SDK guides, you can find the links in the What's Next? section below.

Schema¶

The Schema section of the Realm UI displays information about the structure of the data stored in our linked Atlas cluster. In this section, you should see a cluster called mongodb-atlas that contains two collections: Task and User. You can navigate to the Schema tab to view the JSON Schema that defines the structure of the data in each collection.

While MongoDB's document model allows us to store data in a wide variety of shapes and sizes, Realm Database and Realm Sync require data to follow a set schema. Data that follows this schema synchronizes between the MongoDB Atlas linked data source and devices connected to your Realm app via a client SDK. This schema should match the models defined in client applications, with minor exceptions.

Tip

See:

To learn more about schemas in MongoDB Realm, see the documentation on Realm Schemas.

Authentication¶

In the Authentication Providers tab of the Authentication section, you'll find information about the different ways that users can log into the Task Tracker app. In the provided Task Tracker configuration, users can only log in via "Email/Password" authentication, which lets users define an email username and a secret password known only to them to access their account in your Realm app.

If you click on the Email/Password entry in the list of authentication providers, you can view the details of Task Tracker's Email/Password authentication configuration. There are a few important fields here:

• User Confirmation Method: we've selected "automatically confirm users" so that users can log in immediately after creating an account. In a production application, you might prefer to "send a confirmation email" so that users can confirm ownership of their email accounts.
• Password Reset Method: we've selected "run a password reset function", but resetFunc doesn't actually implement any logic: it always fails. For a production application, you'd want to implement a function that actually resets the user's password if they forget it.

Tip

See:

To learn more about authentication in MongoDB Realm, see the documentation on Authentication.

What's Next?¶

You just built a functional task tracker application backend with MongoDB Realm. Great job!

Now that you have a working Realm application, you can follow one of our client application tutorials to connect to your Realm app and manage tasks from a mobile or web application.

• iOS (Swift)
• Android (Kotlin)
• React Native (JavaScript)
• Web/GraphQL (JavaScript)
• Node