LicenseAcquirer.SetLicenseResponse Method

Syntax

'Declaration
Protected Sub SetLicenseResponse ( _
    licenseResponse As Stream _
)

protected void SetLicenseResponse(
    Stream licenseResponse
)

Exceptions

Remarks

If the LicenseAcquirer is created on demand (from the media element) and if this method is called with nulla null reference (Nothing in Visual Basic), the MediaElement transitions from the AcquiringLicense state to the error state and raises the MediaFailed event corresponding to that.

If the LicenseAcquirer is created on demand (from the media element) and if you are handling license acquisition on your own by overriding OnAcquireLicense, you are expected to call this method before the MediaElement leaves the AcquiringLicense state.

Examples

The LicenseAcquirer class is used by the MediaElement to handle acquiring licenses for DRM encrypted content from a PlayReady License Server. You can subclass the LicenseAcquirer class and add custom logic like adding your own custom authentication scheme to the license request.

The following example shows how to override the LicenseAcquirer class (named "ManualLicenseAcquirer") and have a MediaElement use it to acquire the license.

<StackPanel x:Name="LayoutRoot" Background="Gray" Orientation="Vertical">
   <MediaElement x:Name="myME" Height="100"/>
</StackPanel>

public partial class Page : UserControl
{

    public Page()
    {
      InitializeComponent();
      this.Loaded += new RoutedEventHandler(Page_Loaded);
    }

    void Page_Loaded(object sender, RoutedEventArgs e)
    {
      // Test a full fledged manual acquirer

      // Set the LicenseAcquirer of the MediaElement to the custom License Acquirer
      // defined in this sample.
      myME.LicenseAcquirer = new ManualLicenseAcquirer(myME.Name);

      // Set the License URI to proper License Server address.
      myME.LicenseAcquirer.LicenseServerUriOverride = new Uri("https://contoso.com/myLicenseServer.asmx", UriKind.Absolute);
      myME.MediaFailed += new EventHandler<ExceptionRoutedEventArgs>(myME_MediaFailed);

      // Set the source of the MediaElement to the URL of the media encrypted with WMDRM.
      myME.Source = new Uri("https://contoso.com/wmdrm_url.wmv", UriKind.Absolute);
    }

    void myME_MediaFailed(object sender, ExceptionRoutedEventArgs e)
    {
      string errorMessage = "";
      if (e.ErrorException.ToString().Contains(" 6001 "))
      {
          errorMessage = "The individualization component software failed to" +
                         " download to the user’s computer. This error would" +
                         " come up when the MediaElement is in the Individualizing" +
                         " MediaElementState. One possible reason for this error is" +
                         " that the Silverlight client cannot connect the Microsoft" +
                         " Individualization Server.";
      }
      else if (e.ErrorException.ToString().Contains(" 6004 "))
      {
          errorMessage = " The installation of Silverlight on the client is" +
                         " out of date and needs to be updated.";  
      }
      else
      {
          errorMessage = "MediaFailed: " + e.ErrorException.Message + ".";
      }
      System.Windows.Browser.HtmlPage.Window.Alert(errorMessage);
    }

    // makes license request explicitly
    public class ManualLicenseAcquirer : LicenseAcquirer
    {
      private string challengeString;
      string _mediaElementName;

    public ManualLicenseAcquirer(string mediaElementName)
    {
      _mediaElementName = mediaElementName;
    }

    // The default implementation of OnAcquireLicense calls into the MediaElement to acquire a
    //  license. It is called when the Media pipeline is building a topology and will be raised
    // before MediaOpened is raised.
    protected override void OnAcquireLicense(System.IO.Stream licenseChallenge, Uri licenseServerUri)
    {
      StreamReader sr = new StreamReader(licenseChallenge);
      challengeString = sr.ReadToEnd();

      // Need to resolve the URI for the License Server -- make sure it is correct
      // and store that correct URI as resolvedLicenseServerUri.
      Uri resolvedLicenseServerUri;
      if (LicenseServerUriOverride == null)
        resolvedLicenseServerUri = licenseServerUri;
      else
        resolvedLicenseServerUri = LicenseServerUriOverride;

      // Make a HttpWebRequest to the License Server.
      HttpWebRequest request = WebRequest.Create(resolvedLicenseServerUri) as HttpWebRequest;
      request.Method = "POST";

      // Set ContentType through property    
      request.ContentType = "application/xml";

      //  ADD REQUIRED HEADERS.
      // The headers below are necessary so that error handling and redirects are handled 
      // properly via the Silverlight client.
      request.Headers["msprdrm_server_redirect_compat"] = "false";
      request.Headers["msprdrm_server_exception_compat"] = "false";

      //  Initiate getting request stream  
      IAsyncResult asyncResult = request.BeginGetRequestStream(new AsyncCallback(RequestStreamCallback), request);
    }

    // This method is called when the asynchronous operation completes.
    void RequestStreamCallback(IAsyncResult ar)
    {
      HttpWebRequest request = ar.AsyncState as HttpWebRequest;

      // populate request stream  
      request.ContentType = "text/xml";
      Stream requestStream = request.EndGetRequestStream(ar);
      StreamWriter streamWriter = new StreamWriter(requestStream, System.Text.Encoding.UTF8);

      streamWriter.Write(challengeString);
      streamWriter.Close();

      // Make async call for response  
      request.BeginGetResponse(new AsyncCallback(ResponseCallback), request);
    }

    private void ResponseCallback(IAsyncResult ar)
    {
      HttpWebRequest request = ar.AsyncState as HttpWebRequest;
      WebResponse response = request.EndGetResponse(ar);
      SetLicenseResponse(response.GetResponseStream());
    }
  }
}

Public Class Page
    Inherits UserControl
    
    Public Sub New()
        MyBase.New
        InitializeComponent
        AddHandler Loaded, AddressOf Me.Page_Loaded
    End Sub
    
    Private Sub Page_Loaded(ByVal sender As Object, ByVal e As RoutedEventArgs)
        ' Test a full fledged manual acquirer
        ' Set the LicenseAcquirer of the MediaElement to the custom License Acquirer
        ' defined in this sample.
        myME.LicenseAcquirer = New ManualLicenseAcquirer(myME.Name)
        ' Set the License URI to proper License Server address.
        myME.LicenseAcquirer.LicenseServerUriOverride = New Uri("https://contoso.com/myLicenseServer.asmx", UriKind.Absolute)
        AddHandler myME.MediaFailed, AddressOf Me.myME_MediaFailed
        ' Set the source of the MediaElement to the URL of the media encrypted with WMDRM.
        myME.Source = New Uri("http:, contoso.com/wmdrm_url.wmv", UriKind.Absolute);)
    End Sub
    
    Private Sub myME_MediaFailed(ByVal sender As Object, ByVal e As ExceptionRoutedEventArgs)
        Dim errorMessage As String = ""
        If e.ErrorException.ToString.Contains(" 6001 ") Then
            errorMessage = "The individualization component software failed to" & _
                           " download to the user's computer. This error would" & _
                           " come up when the MediaElement is in the Individualizing" & _
                           " MediaElementState. One possible reason for this error is" & _
                           " that the Silverlight client cannot connect the Microsoft" & _
                           " Individualization Server."
        ElseIf e.ErrorException.ToString.Contains(" 6004 ") Then
            errorMessage = "The installation of Silverlight on the client is" & _
                           " out of date and needs to be updated."
        Else
            errorMessage = "MediaFailed: " & _
                        +  e.ErrorException.Message + "."
        End If
        System.Windows.Browser.HtmlPage.Window.Alert(errorMessage)
    End Sub
    
    ' makes license request explicitly
    Public Class ManualLicenseAcquirer
        Inherits LicenseAcquirer
        
        Private challengeString As String
        
        Private _mediaElementName As String
        
        Public Sub New(ByVal mediaElementName As String)
            MyBase.New
            _mediaElementName = mediaElementName
        End Sub
        
        ' The default implementation of OnAcquireLicense calls into the MediaElement to acquire a
        '  license. It is called when the Media pipeline is building a topology and will be raised
        ' before MediaOpened is raised.
        Protected Overrides Sub OnAcquireLicense(ByVal licenseChallenge As System.IO.Stream, ByVal licenseServerUri As Uri)
            Dim sr As StreamReader = New StreamReader(licenseChallenge)
            challengeString = sr.ReadToEnd
            ' Need to resolve the URI for the License Server -- make sure it is correct
            ' and store that correct URI as resolvedLicenseServerUri.
            Dim resolvedLicenseServerUri As Uri
            If (LicenseServerUriOverride Is Nothing) Then
                resolvedLicenseServerUri = licenseServerUri
            Else
                resolvedLicenseServerUri = LicenseServerUriOverride
            End If
            ' Make a HttpWebRequest to the License Server.
            Dim request As HttpWebRequest = CType(WebRequest.Create(resolvedLicenseServerUri),HttpWebRequest)
            request.Method = "POST"
            ' Set ContentType through property    
            request.ContentType = "application/xml"
            '  ADD REQUIRED HEADERS.
            ' The headers below are necessary so that error handling and redirects are handled 
            ' properly via the Silverlight client.
            request.Headers("msprdrm_server_redirect_compat") = "false"
            request.Headers("msprdrm_server_exception_compat") = "false"
            '  Initiate getting request stream  
            Dim asyncResult As IAsyncResult = request.BeginGetRequestStream(New AsyncCallback(RequestStreamCallback), request)
        End Sub
        
        ' This method is called when the asynchronous operation completes.
        Private Sub RequestStreamCallback(ByVal ar As IAsyncResult)
            Dim request As HttpWebRequest = CType(ar.AsyncState,HttpWebRequest)
            ' populate request stream  
            request.ContentType = "text/xml"
            Dim requestStream As Stream = request.EndGetRequestStream(ar)
            Dim streamWriter As StreamWriter = New StreamWriter(requestStream, System.Text.Encoding.UTF8)
            streamWriter.Write(challengeString)
            streamWriter.Close
            ' Make async call for response  
            request.BeginGetResponse(New AsyncCallback(ResponseCallback), request)
        End Sub
        
        Private Sub ResponseCallback(ByVal ar As IAsyncResult)
            Dim request As HttpWebRequest = CType(ar.AsyncState,HttpWebRequest)
            Dim response As WebResponse = request.EndGetResponse(ar)
            SetLicenseResponse(response.GetResponseStream)
        End Sub
    End Class
End Class

Version Information

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.

See Also

Reference

Other Resources