This section describes how to edit the DSN configuration and then authenticate and connect to Azure Cosmos DB APIs.

DSN Configuration

You can use the Microsoft ODBC Data Source Administrator to edit the DSN configuration. Note that the installation process creates a both a user DSN and a system DSN, as described in Installing the Connector.

Note: The connector stores connection information in the Windows registry. To ensure that the connector can write to the registry, either run Power BI as an administrator or use a User DSN for your connection instead of a System DSN.

User DSN

Complete the following steps to edit the DSN configuration:

1. Select Start > Search, and enter ODBC Data Sources in the Search box.
2. Choose the version of the ODBC Administrator that corresponds to the bitness of your Power BI Desktop installation (32-bit or 64-bit).
3. Select the system data source and click Configure.
4. Edit the information on the Connection tab and click OK.

System DSN

Configure the system DSN the same way as the user DSN, except you will need to switch to the System DSN tab before performing Step 3.

If you're using Power BI's On-Premises Data Gateway with Standard mode, you must use the system DSN.

You must also specify a valid location for OAuthSettingsLocation (a path where OAuth credentials are locally stored to avoid repeated OAuth prompts).

This is because the Standard mode runs on service mode and can only access permitted locations, such as C:\Windows\ServiceProfiles\PBIEgwService\AppData\Local\Microsoft\On-premises data gateway.

Before You Connect

Role Assignment

Ensure that the Azure identity has the correct role assignment. The identity is the account that you log in to the browser during AzureAD authentication or the Application itself for AzureServicePrincipal authentication. Please visit the link below for more details:

Configure role-based access control for your Azure Cosmos DB account with Azure AD

You can either assign one of the built-in role definitions:

• CosmosDB Built-in Data Reader
• CosmosDB Built-in Data Contributor

or create your own custom role definitions. You must also set the scope of the role assignment, where "/" means that the identity has access to all the databases.

Connecting to Azure Cosmos DB

Account Key

Log in to the Azure Portal, select Azure Cosmos DB, and select your account.

Set the following to authenticate:

• AccountEndpoint: The Cosmos DB account URL. Set this to the URI value found in the Settings > Keys blade of the Cosmos DB account.
• AccountKey: A master key token or a resource token for connecting to Azure Cosmos DB. Set this to the PRIMARY KEY value found in the Settings > Keys blade of the Cosmos DB account.
• TokenType: (optional). Set this to "master" (the default value) if you are using a Master Token, which is a full permissions token generated during account creation. Otherwise, set this property to "resource" if you are using a Resource Token, which is a custom permissions token generated when a database user is set up.

Azure AD

Azure AD is Microsoft’s multi-tenant, cloud-based directory and identity management service. It is user-based authentication that requires that you set AuthScheme to AzureAD.

Desktop Applications

CData provides an embedded OAuth application that simplifies authentication at the desktop.

Before you connect, set the following variables:

• InitiateOAuth: GETANDREFRESH. Used to automatically get and refresh the OAuthAccessToken. CData provides an embedded OAuth application that simplifies authentication at the desktop; that is, in situations where the user is using a local server not connected to the internet.

  You can also authenticate from the desktop via a custom OAuth application, which you configure and register at the Azure Cosmos DB console. For further information, see Creating a Custom OAuth Application.

• Custom Azure AD applications only:
  • OAuthClientId: The client Id assigned when you registered your custom OAuth application.
  • OAuthClientSecret: The client secret assigned when you registered your custom OAuth application.
  • CallbackURL: The redirect URI defined when you registered your custom OAuth application.

When you connect, the connector opens the Azure Cosmos DB's OAuth endpoint in your default browser. Log in and grant permissions to the application.

When the access token expires, the connector refreshes it automatically.

Headless Machines

If you need to log in to a resource that resides on a headless machine, you must authenticate on another device that has an internet browser. You can do this in either of the following ways:

• Obtain the OAuthVerifier value as described in Obtain and Exchange a Verifier Code, below.
• Install the connector on another machine and transfer the OAuth authentication values after you authenticate through the usual browser-based flow.

After you execute either of these options, configure the driver to automatically refresh the access token on the headless machine.

Obtaining and Exchanging a Verifier Code

To obtain a verifier code, you must authenticate at the OAuth authorization URL from a machine with an internet browser, and obtain the OAuthVerifier connection property.

1. Choose one of these options:
   • If you are using the Embedded OAuth Application, click Azure Cosmos DB OAuth endpoint to open the endpoint in your browser.
   • If you are using a custom OAuth application, set the following properties to create the Authorization URL:
     • InitiateOAuth: OFF.
     • OAuthClientId: The client Id assigned when you registered your application.
     • OAuthClientSecret: The client secret assigned when you registered your application.
     After the Authorization URL is established, call the GetOAuthAuthorizationURL stored procedure with the appropriate CallbackURL. Open the URL returned by the stored procedure in a browser.

2. Log in and grant permissions to the connector. You are redirected to the callback URL, which contains the verifier code.
3. Save the value of the verifier code. Later you will set this in the OAuthVerifier connection property.

Next, exchange the OAuth verifier code for OAuth refresh and access tokens.

To obtain the OAuth authentication values, set these properties:

• InitiateOAuth: REFRESH.
• OAuthVerifier: The verifier code.
• OAuthSettingsLocation: The location of the file where the driver saves the OAuth token values that persist across connections.
• Custom applications only:
  • OAuthClientId: (custom applications only) Set this to the client Id in your custom OAuth application settings.
  • OAuthClientSecret: (custom applications only) Set this to the client secret in the custom OAuth application settings.

After the OAuth settings file is generated, re-set the following properties to connect:

• InitiateOAuth: REFRESH.
• OAuthSettingsLocation: The location containing the encrypted OAuth authentication values. Make sure this location grants read and write permissions to the connector to enable the automatic refreshing of the access token.
• Custom applications only:
  • OAuthClientId: The client Id assigned when you registered your application.
  • OAuthClientSecret: The client secret assigned when you registered your application.

Transferring OAuth Settings

Prior to connecting on a headless machine, you must create and install a connection with the driver on a device that supports an internet browser. Set the connection properties as described in "Desktop Applications" above.

After completing the instructions in "Desktop Applications", the resulting authentication values are encrypted and written to the location specified by OAuthSettingsLocation. The default filename is OAuthSettings.txt.

Once you have successfully tested the connection, copy the OAuth settings file to your headless machine.

On the headless machine, set the following connection properties to connect to data:

• InitiateOAuth: REFRESH.
• OAuthSettingsLocation: The location of your OAuth settings file. Make sure this location gives read and write permissions to the connector to enable the automatic refreshing of the access token.
• Custom applications only:
  • OAuthClientId: The client Id assigned when you registered your application.
  • OAuthClientSecret: The client secret assigned when you registered your application.

Azure Service Principal

Azure Service Principal is role-based application-based authentication. This means that authentication is done per application, rather than per user. All tasks taken on by the application are executed without a default user context, but based on the assigned roles. The application access to the resources is controlled through the assigned roles' permissions.

For information about how to set up Azure Service Principal authentication, see Creating a Custom OAuth Application.