Azure Cosmos DB: Build a MongoDB API console app with Java and the Azure portal

Azure Cosmos DB is Microsoft’s globally distributed multi-model database service. You can quickly create and query document, key/value, and graph databases, all of which benefit from the global distribution and horizontal scale capabilities at the core of Azure Cosmos DB.

This quick start demonstrates how to create an Azure Cosmos DB account, document database, and collection using the Azure portal. You'll then build and deploy a console app built on the MongoDB Java driver.

Prerequisites

Before you can run this sample, you must have the following prerequisites:

  • JDK 1.7+ (Run apt-get install default-jdk if you don't have JDK)
  • Maven (Run apt-get install maven if you don't have Maven)

If you don't have an Azure subscription, create a free account before you begin.

Alternatively, you can Try Azure Cosmos DB for free without an Azure subscription, free of charge and commitments. Or you can use the Azure Cosmos DB Emulator for this tutorial with a connection string of

mongodb://localhost:C2y6yDjf5/R+ob0N8A7Cgv30VRDJIWEHLM+4QDU5DE2nQ9nDuVTqobD4b8mGGyPMbIZnqyMsEcaGQy67XIw/Jw==@localhost:10255/admin?ssl=true

Create a database account

  1. In a new window, sign in to the Azure portal.
  2. In the left menu, click New, click Databases, and then under Azure Cosmos DB, click Create.

    Screen shot of the Azure portal, highlighting More Services, and Azure Cosmos DB

  3. In the New account blade, specify the desired configuration for the Azure Cosmos DB account.

    With Azure Cosmos DB, you can choose one of four programming models: Gremlin (graph), MongoDB, SQL (DocumentDB), and Table (key-value).

    In this quick start we'll be programming against the MongoDB API so you'll choose MongoDB as you fill out the form. But if you have graph data for a social media app, document data from a catalog app, or key/value (table) data, realize that Azure Cosmos DB can provide a highly available, globally-distributed database service platform for all your mission-critical applications.

    Fill out the New account blade using the information in the table as a guide.

    Screen shot of the New Azure Cosmos DB blade

    Setting Suggested value Description
    ID Unique value A unique name you choose to identify the Azure Cosmos DB account. documents.azure.com is appended to the ID you provide to create your URI, so use a unique but identifiable ID. The ID may contain only lowercase letters, numbers, and the '-' character, and must be between 3 and 50 characters.
    API MongoDB The API determines the type of account to create. Azure Cosmos DB provides five APIs to suits the needs of your application: SQL (document database), Gremlin (graph database), MongoDB (document database), Azure Table, and Cassandra, each which currently require a separate account.

    Select MongoDB because in this quickstart you are creating a document database that is queryable using MongoDB.

    Learn more about the MongoDB API
    Subscription Your subscription The Azure subscription that you want to use for the Azure Cosmos DB account.
    Resource Group The same value as ID The new resource group name for your account. For simplicity, you can use the same name as your ID.
    Location The region closest to your users The geographic location in which to host your Azure Cosmos DB account. Choose the location closest to your users to give them the fastest access to the data.
  4. Click Create to create the account.

  5. On the toolbar, click Notifications to monitor the deployment process.

    Deployment started notification

  6. When the deployment is complete, open the new account from the All Resources tile.

    Azure Cosmos DB account on the All Resources tile

Add a collection

Name your new database, db, and your new collection, coll.

You can now use the Data Explorer tool in the Azure portal to create a database and collection.

  1. Click Data Explorer > New Collection.

    The Add Collection area is displayed on the far right, you may need to scroll right to see it.

    The Azure portal Data Explorer, Add Collection blade

  2. In the Add collection page, enter the settings for the new collection.

    Setting Suggested value Description
    Database id Tasks Enter Tasks as the name for the new database. Database names must contain from 1 through 255 characters, and they cannot contain /, \, #, ?, or a trailing space.
    Collection id Items Enter Items as the name for your new collection. Collection ids have the same character requirements as database names.
    Storage capacity Fixed (10 GB) Change the value to Fixed (10 GB). This value is the storage capacity of the database.
    Throughput 400 RU Change the throughput to 400 request units per second (RU/s). If you want to reduce latency, you can scale up the throughput later.
    Partition key /category A partition key that distributes data evenly to each partition. Selecting the correct partition key is important in creating a performant collection. To learn more, see Designing for partitioning.

    Click OK.

    Data Explorer displays the new database and collection.

    The Azure portal Data Explorer, showing the new database and collection

Clone the sample application

Now let's clone a MongoDB API app from github, set the connection string, and run it. You'll see how easy it is to work with data programmatically.

  1. Open a git terminal window, such as git bash, and cd to a working directory.

  2. Run the following command to clone the sample repository.

    git clone https://github.com/Azure-Samples/azure-cosmos-db-mongodb-java-getting-started.git
    
  3. Then open the solution file in Visual Studio.

Review the code

Let's make a quick review of what's happening in the app. Open the Program.cs file and you'll find that these lines of code create the Azure Cosmos DB resources.

  • The DocumentClient is initialized.

    MongoClientURI uri = new MongoClientURI("FILLME");`
    
    MongoClient mongoClient = new MongoClient(uri);            
    
  • A new database and collection are created.

    MongoDatabase database = mongoClient.getDatabase("db");
    
    MongoCollection<Document> collection = database.getCollection("coll");
    
  • Some documents are inserted using MongoCollection.insertOne

    Document document = new Document("fruit", "apple")
    collection.insertOne(document);
    
  • Some queries are performed using MongoCollection.find

    Document queryResult = collection.find(Filters.eq("fruit", "apple")).first();
    System.out.println(queryResult.toJson());       
    

Update your connection string

Now go back to the Azure portal to get your connection string information and copy it into the app.

  1. From the Account, select Quick Start, select Java, then copy the connection string to your clipboard

  2. Open the Program.java file, replace the argument to the MongoClientURI constructor with the connection string. You've now updated your app with all the info it needs to communicate with Azure Cosmos DB.

Run the console app

  1. Run mvn package in a terminal to install required npm modules

  2. Run mvn exec:java -D exec.mainClass=GetStarted.Program in a terminal to start your Java application.

You can now use Robomongo / Studio 3T to query, modify, and work with this new data.

Review SLAs in the Azure portal

The throughput, storage, availability, latency, and consistency of the resources in your account are monitored in the Azure portal. Let's take a quick look at these metrics.

  1. Click Metrics in the navigation menu.

    Metrics in the Azure portal

  2. Click through each of the tabs so you're aware of the metrics Azure Cosmos DB provides.

    Each chart that's associated with the Azure Cosmos DB Service Level Agreements (SLAs) provides a line that shows if any of the SLAs have been violated. Azure Cosmos DB makes monitoring your SLAs transparent with this suite of metrics.

    Azure Cosmos DB metrics suite

Clean up resources

If you're not going to continue to use this app, delete all resources created by this quickstart in the Azure portal with the following steps:

  1. From the left-hand menu in the Azure portal, click Resource groups and then click the name of the resource you created.
  2. On your resource group page, click Delete, type the name of the resource to delete in the text box, and then click Delete.

Next steps

In this quickstart, you've learned how to create an Azure Cosmos DB account, create a collection using the Data Explorer, and run a console app. You can now import additional data to your Cosmos DB account.