Build Cosmos DB-Connected Apps in Mendix

Mendix is a high-productivity app platform that allows you to build and maintain both mobile and web applications at-scale. When paired with CData Connect AI, Mendix provides instant, cloud-to-cloud access to Cosmos DB data for applications. This article demonstrates how to connect to a CData Connect AI data source from within Mendix.

CData Connect AI provides a pure cloud-to-cloud interface for Cosmos DB, allowing you to import data from live Cosmos DB data in Mendix — without replicating the data to a natively supported database. As you build web and mobile applications from within Mendix, CData Connect AI pushes all supported SQL operations (filters, JOINs, etc.) directly to Cosmos DB, leveraging server-side processing to return the requested Cosmos DB data quickly.

Configure Cosmos DB Connectivity for Mendix

To work with Cosmos DB data from Mendix, we need to connect to Cosmos DB from Connect AI, provide user access to the connection, and create a Workspace for the Cosmos DB data.

Connect to Cosmos DB from Connect AI

CData Connect AI uses a straightforward, point-and-click interface to connect to data sources.

1. Log into Connect AI, click Sources, and then click Add Connection
👁 Adding a Connection

2. Select "Cosmos DB" from the Add Connection panel
👁 Selecting a data source

3. Enter the necessary authentication properties to connect to Cosmos DB.

   To obtain the connection string needed to connect to a Cosmos DB account using the SQL API, log in to the Azure Portal, select Azure Cosmos DB, and select your account. In the Settings section, click Connection String and set the following values:

   • AccountEndpoint: The Cosmos DB account URL from the Keys blade of the Cosmos DB account
   • AccountKey: In the Azure portal, navigate to the Cosmos DB service and select your Azure Cosmos DB account. From the resource menu, go to the Keys page. Find the PRIMARY KEY value and set AccountKey to this value.
   👁 Configuring a connection (Salesforce is shown)
   
4. Click Save & Test
5. Navigate to the Permissions tab in the Add Cosmos DB Connection page and update the User-based permissions. 👁 Updating permissions
   

Add a Personal Access Token

When connecting to Connect AI through the REST API, the OData API, or the Virtual SQL Server, a Personal Access Token (PAT) is used to authenticate the connection to Connect AI. It is best practice to create a separate PAT for each service to maintain granularity of access.

1. Click on the Gear icon () at the top right of the Connect AI app to open the settings page.
2. On the Settings page, go to the Access Tokens section and click Create PAT.
3. Give the PAT a name and click Create. 👁 Creating a new PAT
   
4. The personal access token is only visible at creation, so be sure to copy it and store it securely for future use.

Configure Cosmos DB Endpoints for Mendix

After connecting to Cosmos DB, create a workspace for your desired table(s).

1. Navigate to the Workspaces page and click Add to create a new Workspace (or select an existing workspace). 👁 The Workspaces page.
   👁 Adding a new Workspace.
   
2. Click Add to add new assets to the Workspace.
3. Select the Cosmos DB connection (e.g. CosmosDB1) and click Next. 👁 Selecting an Asset (Salesforce is shown).
   
4. Select the table(s) you wish to work with and click Confirm. 👁 Selecting Tables (Salesforce is shown).
   
5. Make note of the OData Service URL for your workspace, e.g. https://cloud.cdata.com/api/odata/{workspace_name}

With the connection, PAT, and Workspace configured, you are ready to connect to Cosmos DB data from Mendix.

Build a Cosmos DB-Connected App

Downloading the OData Metadata File

When creating a connection in Mendix, the connection flow requires a Data Source Contract File. Follow these steps to download the OData metadata file for CData Connect AI using curl, a command line tool:

1. Open a command-line window for your operating system. On Windows, open the start menu, type cmd, and press the Enter key to open a command prompt. On macOS and Linux, open a Terminal window.
2. To check if curl is installed on your system, type curl -help and press the enter key. If it is not installed, install it from the curl website.
3. Issue the following curl command, replacing USER with your CData Connect AI username and PAT with the PAT you generated above:

   curl -u USER:PAT https://cloud.cdata.com/api/odata/{workspace_name}/$metadata -o metadata.xml

4. Locate the metadata.xml file that the curl command created and move it to an accessible location.

Connecting to CData Connect AI in Mendix

Follow these steps to establish a connection from Mendix to CData Connect AI:

1. Login to Mendix and open the Data Hub page.
👁 Mendix landing page

2. In the Register a Data Source section, select OData.
👁 Registering an OData data source

3. Upload the metadata.xml file from the steps above and click Next.
👁 Uploading metadata file

4. Enter your desired values for Data Source Name and Data Source Version. In the Data Source Relative Path field, enter /api/odata/{workspace_name} and click Next.
👁 Creating the data source

5. On the Application information page, click Register a new application.
👁 Register new app

6. Enter a name in Application Name and select a technical owner (by default, this is the user who is currently logged in).
👁 Filling in fields for the app

7. Click Next. In the Environment Name field, enter a desired name (for example, CData Connect AI). In the Environment Location field, enter https://cloud.cdata.com and select the appropriate Environment Type (e.g. Production), depending on what is needed.
👁 Creating the environment

8. Click Done! to create your connection.
👁 Finalizing the connection

You can now use your connection in Mendix Studio Pro to easily create applications with access to live Cosmos DB data.

Get CData Connect AI

To get live data access to hundreds of SaaS, Big Data, and NoSQL sources directly from your cloud applications, try CData Connect AI today!