Access Token Authentication for Power BI Embedded securely.
1. Authentication via AAD: The route to user authentication for Power BI Embedded is using Azure Active Directory. You can do this by registering the app through Azure Portal, i.e., Azure Active Directory. A service principal would then be created that views the Power BI service.
Use OAuth2 to authenticate the application and get an access token. Thus, it would be securely issued and tied to a user's Azure AD identity.
2. Generate and Store Access Token Securely:
Most often, this is done either through a master user account or service principal, authenticating and obtaining the access token. It is always best to go for his service principal to automate processes since it allows much more granular control of permissions.
Service Principal Flow: The first source of authentication is the service principal. After that, you will generate the embedded token using the Power BI REST API. Make sure that the service principal only has the permissions necessary to access the Power BI workspaces or reports it needs to reach.
Once it is generated, you should keep the token on a secure site (for example, in Azure Key Vault) to avoid exposing it to front-end code. Do not ever store these credentials on the client-side app for unauthorized access.
Embedding Token Generation (via Power BI REST API):
Utilize the Power BI REST API to generate an embed token. The GenerateTokenInGroup API allows the creation of tokens for reports, dashboards, and tiles. In order to create the embed token, you'll require the workspace (group) ID and the report ID.
To generate a secure token, you will use a back-end service such as ASP.NET, Node.js, or Python to interact with the Power BI REST API. This prevents exposing credentials and tokens to the client.
4. Implement Token Expiration and Refresh:
The tokens generated for Power BI Embedded usually have a short lifespan, often up to one hour. Implement logic to handle token expiry.
Store the token expiration time and automatically refresh it before it expires to ensure that the user experience is never interrupted. Refresh tokens can be obtained by making new ones through the same authentication mechanism via Power BI REST API.
5. Use Azure Managed Identity for Better Security (Optional):
Adopt Managed Identity in Azure for better security and easy management. Managed Identity grants access to Azure resources such as Power BI without creating the need for the management of credentials. This reduces the likelihood of credential theft.
This is useful mainly when you host your embedded Power BI solution within an Azure environment (e.g., Azure App Services, Azure Functions, Azure Virtual Machines, etc.).
Secure Access to Power BI Resources:
Configure role-based access control in Azure AD for access restriction to Power BI workspaces and reports. Assign appropriate roles like Viewer or Contributor for service principal or user, which helps to make sure that they will have the required permissions.
While the above enforces the use of MFA and trusted IPs, Azure AD, through its Conditional Access policies, will add yet another layer of security.
7. Token Management:
Track and log token usage to find terminations regarding unauthorized attempts, and use Azure Monitor and Azure Security Center to provide insights into token usage activities to ensure compliance.
Rotate your passwords quite often to reduce leak or even breach possibilities and damage assignment while refreshing service principal passwords using client secret expiration methods.
All of the best practices allow secure generation and storage of Power BI Embedded access tokens and management. In addition, it is scalable and maintains very high levels of security.
