3. Provision CosmosDB on Azure with MongoDB API

Goal

In this tutorial, you will learn how to:

1. Provision an Azure CosmosDB account using the Azure Portal.
2. Configure the account to use the MongoDB API with serverless capacity and Request Units (RU).

Prerequisites

• An active Azure subscription.
• Azure Portal access (https://portal.azure.com).
• Basic understanding of MongoDB concepts.

Step-by-step Guide

1. Log in to Azure Portal

Steps:

1. Open a web browser and navigate to the Azure Portal.
2. Sign in using your Azure account credentials.

2. Create a Resource Group

We’ll create a resource group to organize the resources related to CosmosDB.

Steps:

1. In the Azure Portal, search for “Resource groups” in the search bar.
2. Click “Create” and fill in the following:
   • Subscription: Choose your subscription.
   • Resource Group Name: NewsletterRG
   • Region: Choose a region (e.g., North Europe).
3. Click Review + Create and then Create.

3. Provision CosmosDB with MongoDB API

We’ll now create a CosmosDB account configured to use the MongoDB API.

Steps:

1. In the Azure Portal, search for Azure Cosmos DB and click Create.
2. Select Azure Cosmos DB for MongoDB and click Create.
3. Select ARequest unit (RU) database account and click Create.
4. Configure the CosmosDB account:
   • Subscription: Select your subscription.
   • Resource Group: Choose NewsletterRG.
   • Account Name: cosmosdb<date><time> (must be globally unique).
   • Location: North Europe.
   • Capacity Mode: Select Serverless.
5. Click Review + create and then Create

💡 Information
The MongoDB API on CosmosDB allows you to use MongoDB tools and drivers.

4. Connect to the Database

Now we’ll connect to the CosmosDB using the MongoDB connection string.

Steps:

1. In your CosmosDB account, go to Connection String under Settings.
2. Copy the Primary connection string.

💡 Information
The connection string contains credentials, so keep it secure.

3. Login to your VM and set the connection string as an environment variable

sudo nano /etc/Newsletter/.env

ASPNETCORE_ENVIRONMENT=Production
ASPNETCORE_URLS="http://*:5000"
MongoDbSettings__ConnectionString=mongodb://cosmosdb1111...
DatabaseToUse=MongoDb

💡 Note Note how the json hierarchy in appsettings.json is replaced by dubble underscore (__).

...
},
  "MongoDbSettings": {
    "ConnectionString": "SET PROD CONNECTION STRING",
    ...
  },
...

4. Restart the service running the dotnet app

sudo systemctl restart Newsletter.service

6. Insert and Query Data

Now browse to the app and add some Subscribers. Make sure it look alright in the app.

💡 Verification

1. Navigate to your CosmosDB account.
2. In the left-hand menu, select Data Explorer.
3. You should see the posts from the app

💡 Information
Collections are equivalent to tables in relational databases. Documents are stored in collections, and they are formatted as JSON.

You now have a CosmosDB with MongoDB API running on Azure! 🚀