Refreshing the Report Token

Hi  PowerBIUserHoop ,

As far as I know, access tokens generally expire in 60 minutes or less, and you'll need an access token policy and an update to it.

Refresh tokens in the Microsoft identity platform - Microsoft identity platform | Microsoft Learn

This is the related document, you can view this content:

oauth - Handling Expired Refresh Tokens in ASP.NET Core - Stack Overflow

Solved: Get data from API with token that expires - Microsoft Fabric Community

Solved: Token expiring in Power BI embedded (error 403) - Microsoft Fabric Community

Best Regards,

Liu Yang

If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.

To automatically refresh the token in an ASP.NET Core application for a Power BI report, you can implement an approach that fetches a new access token before the current one expires. Here are some steps you can follow:

 1. Implement a Token Refresh Method
Set up a method to retrieve a new token from Azure Active Directory (AAD) when the existing token expires. This usually involves setting up a method to request a new token using the client credentials or authorization flow.

csharp

public async Task<string> GetAccessToken()
{
var app = ConfidentialClientApplicationBuilder.Create(clientId)
.WithClientSecret(clientSecret)
.WithAuthority(new Uri(authority))
.Build();

var scopes = new string[] { "https://analysis.windows.net/powerbi/api/.default" };
AuthenticationResult result = await app.AcquireTokenForClient(scopes).ExecuteAsync();
return result.AccessToken;
}

2. Use a Timer or Background Service
Set up a background task or timer in ASP.NET Core to refresh the token at regular intervals. A timer could be set to request a new token just before the old token expires. Alternatively, ASP.NET Core’s `IHostedService` can be used to handle token refresh in the background.

For example:

csharp

public class TokenRefreshService : IHostedService, IDisposable
{
private Timer _timer;
private readonly TokenProvider _tokenProvider; // Your service to get tokens

public TokenRefreshService(TokenProvider tokenProvider)
{
_tokenProvider = tokenProvider;
}

public Task StartAsync(CancellationToken cancellationToken)
{
_timer = new Timer(RefreshToken, null, TimeSpan.Zero, TimeSpan.FromMinutes(50)); // Set before expiration
return Task.CompletedTask;
}

private async void RefreshToken(object state)
{
await _tokenProvider.RefreshToken(); // Method to refresh and store token
}

public Task StopAsync(CancellationToken cancellationToken)
{
_timer?.Change(Timeout.Infinite, 0);
return Task.CompletedTask;
}

public void Dispose()
{
_timer?.Dispose();
}
}

3. Configure Token Refresh in the Frontend (JavaScript/HTML)
In your frontend code, handle token expiration errors by requesting a new token. For instance, if you receive the `ClientError_TokenExpired` error, refresh the token and re-initialize the Power BI embedded report.

javascript

function refreshReport() {
powerbi.get(reportContainer).embedConfig.accessToken = '<new_token>'; // Assign refreshed token
powerbi.get(reportContainer).refresh(); // Reload the report
}

 4. Store the Token Securely and Update It
When you obtain a new token, store it securely (for example, in-memory cache) and ensure all subsequent requests use the latest token. Update your embed configurations or any other services that use this token.

Additional Tips
- Token Lifetime: Check your access token's lifetime and adjust the refresh frequency accordingly. For example, if the token lasts 60 minutes, you might refresh every 50 minutes.
- Use Azure AD Library: Use the Microsoft Authentication Library (MSAL) to manage tokens if possible; it includes built-in token caching and refresh handling.

Let me know if you need more details on any specific part!