Merge pull request #118669 from longb1/patch-1

Update authentication.md

Author: Jak-MS

articles/ai-services/authentication.md

@@ -216,11 +216,12 @@ Now that you have a custom subdomain associated with your resource, you're going
    New-AzADServicePrincipal -ApplicationId <APPLICATION_ID>
    ```
 
-   >[!NOTE]
+   > [!NOTE]
    > If you register an application in the Azure portal, this step is completed for you.
 
 3. The last step is to [assign the "Cognitive Services User" role](/powershell/module/az.Resources/New-azRoleAssignment) to the service principal (scoped to the resource). By assigning a role, you're granting service principal access to this resource. You can grant the same service principal access to multiple resources in your subscription.
-   >[!NOTE]
+
+   > [!NOTE]
    > The ObjectId of the service principal is used, not the ObjectId for the application.
    > The ACCOUNT_ID will be the Azure resource Id of the Azure AI services account you created. You can find Azure resource Id from "properties" of the resource in Azure portal.
 
@@ -239,32 +240,31 @@ In this sample, a password is used to authenticate the service principal. The to
    ```
 
 2. Get a token:
-   > [!NOTE]
-   > If you're using Azure Cloud Shell, the `SecureClientSecret` class isn't available. 
-
-   #### [PowerShell](#tab/powershell)
    ```powershell-interactive
-   $authContext = New-Object "Microsoft.IdentityModel.Clients.ActiveDirectory.AuthenticationContext" -ArgumentList "https://login.windows.net/<TENANT_ID>"
-   $secureSecretObject = New-Object "Microsoft.IdentityModel.Clients.ActiveDirectory.SecureClientSecret" -ArgumentList $SecureStringPassword   
-   $clientCredential = New-Object "Microsoft.IdentityModel.Clients.ActiveDirectory.ClientCredential" -ArgumentList $app.ApplicationId, $secureSecretObject
-   $token=$authContext.AcquireTokenAsync("https://cognitiveservices.azure.com/", $clientCredential).Result
-   $token
-   ```
+   $tenantId = $context.Tenant.Id
+   $clientId = $app.ApplicationId
+   $clientSecret = "<YOUR_PASSWORD>"
+   $resourceUrl = "https://cognitiveservices.azure.com/"
    
-   #### [Azure Cloud Shell](#tab/azure-cloud-shell)
-   ```Azure Cloud Shell
-   $authContext = New-Object "Microsoft.IdentityModel.Clients.ActiveDirectory.AuthenticationContext" -ArgumentList "https://login.windows.net/<TENANT_ID>"
-   $clientCredential = New-Object "Microsoft.IdentityModel.Clients.ActiveDirectory.ClientCredential" -ArgumentList $app.ApplicationId, <YOUR_PASSWORD>
-   $token=$authContext.AcquireTokenAsync("https://cognitiveservices.azure.com/", $clientCredential).Result
-   $token
-   ``` 
-
-   ---
+   $tokenEndpoint = "https://login.microsoftonline.com/$tenantId/oauth2/token"
+   $body = @{
+       grant_type    = "client_credentials"
+       client_id     = $clientId
+       client_secret = $clientSecret
+       resource      = $resourceUrl
+   }
+   
+   $responseToken = Invoke-RestMethod -Uri $tokenEndpoint -Method Post -Body $body
+   $accessToken = $responseToken.access_token
+   ```
 
+   > [!NOTE]
+   > Anytime you use passwords in a script, the most secure option is to use the PowerShell Secrets Management module and integrate with a solution such as Azure KeyVault.
+  
 3. Call the Computer Vision API:
    ```powershell-interactive
    $url = $account.Endpoint+"vision/v1.0/models"
-   $result = Invoke-RestMethod -Uri $url  -Method Get -Headers @{"Authorization"=$token.CreateAuthorizationHeader()} -Verbose
+   $result = Invoke-RestMethod -Uri $url  -Method Get -Headers @{"Authorization"="Bearer $accessToken"} -Verbose
    $result | ConvertTo-Json
    ```