Understanding the protected content workflow

The following steps describe the workflow for pre-loading the voucher for a protected media file using a DRMContentData object.

1. Get the binary metadata for the packaged content. If using the Adobe Access Java Reference Packager, this metadata file is automatically generated with a .metadata extension. You could, for example, download this metadata using the URLLoader class.

2. Create a DRMContentData object, passing the metadata to the constructor function:

   var drmData:DRMContentData = new DRMContentData( metadata );

3. The rest of the steps are identical to the workflow described in Understanding the protected content workflow.

The following steps describe the workflow for pre-loading the voucher for a DRM-protected media file using preloadEmbeddedMetadata():

1. Download and store the media file. (DRM metadata can only be pre-loaded from locally stored files.)

2. Create the NetConnection and NetStream objects, supplying implementations for the onDRMContentData() and onPlayStatus() callback functions of the NetStream client object.

3. Create a NetStreamPlayOptions object and set the stream property to the URL of the local media file.

4. Call the NetStream preloadEmbeddedMetadata(), passing in the NetStreamPlayOptions object identifying the media file to parse.

5. If the media file contains DRM metadata, then the onDRMContentData() callback function is invoked. The metadata is passed to this function as a DRMContentData object.

6. Use the DRMContentData object to obtain the voucher using the DRMManager loadVoucher() method.

   If the value of the authenticationMethod property of the DRMContentData object is flash.net.drm.AuthenticationMethod.USERNAME_AND_PASSWORD, authenticate the user on the media rights server before loading the voucher. The serverURL and domain properties of the DRMContentData object can be passed to the DRMManager authenticate() method, along with the user’s credentials.

7. The onPlayStatus() callback function is invoked when file parsing is complete. If the onDRMContentData() function has not been called, the file does not contain the metadata required to obtain a voucher. This missing call also possibly means that Adobe Access does not protect this file.

The following code example for AIR illustrates how to preload a voucher for a local media file:

package 
{ 
import flash.display.Sprite; 
import flash.events.DRMAuthenticationCompleteEvent; 
import flash.events.DRMAuthenticationErrorEvent; 
import flash.events.DRMErrorEvent;   
import flash.ev ents.DRMStatusEvent; 
import flash.events.NetStatusEvent; 
import flash.net.NetConnection; 
import flash.net.NetStream; 
import flash.net.NetStreamPlayOptions; 
import flash.net.drm.AuthenticationMethod; 
import flash.net.drm.DRMContentData; 
import flash.net.drm.DRMManager; 
import flash.net.drm.LoadVoucherSetting;   
public class DRMPreloader extends Sprite  
{ 
     private var videoURL:String = "app-storage:/video.flv"; 
    private var userName:String = "user"; 
    private var password:String = "password";  
    private var preloadConnection:NetConnection; 
    private var preloadStream:NetStream; 
    private var drmManager:DRMManager = DRMManager.getDRMManager(); 
    private var drmContentData:DRMContentData; 
    public function DRMPreloader():void { 
        drmManager.addEventListener( 
            DRMAuthenticationCompleteEvent.AUTHENTICATION_COMPLETE, 
            onAuthenticationComplete); 
        drmManager.addEventListener(DRMAuthenticationErrorEvent.AUTHENTICATION_ERROR, 
            onAuthenticationError);             
        drmManager.addEventListener(DRMStatusEvent.DRM_STATUS, onDRMStatus); 
        drmManager.addEventListener(DRMErrorEvent.DRM_ERROR, onDRMError); 
        preloadConnection = new NetConnection(); 
        preloadConnection.addEventListener(NetStatusEvent.NET_STATUS, onConnect); 
        preloadConnection.connect(null);            
    } 
 
    private function onConnect( event:NetStatusEvent ):void 
    { 
        preloadMetadata(); 
    } 
    private function preloadMetadata():void 
    { 
        preloadStream = new NetStream( preloadConnection ); 
        preloadStream.client = this; 
        var options:NetStreamPlayOptions = new NetStreamPlayOptions(); 
        options.streamName = videoURL; 
        preloadStream.preloadEmbeddedData( options );                         
    }     
    public function onDRMContentData( drmMetadata:DRMContentData ):void 
    { 
        drmContentData = drmMetadata; 
        if ( drmMetadata.authenticationMethod == AuthenticationMethod.USERNAME_AND_PASSWORD ) 
        { 
            authenticateUser(); 
        } 
        else 
            { 
                getVoucher(); 
            } 
    } 
    private function getVoucher():void 
    { 
        drmManager.loadVoucher( drmContentData, LoadVoucherSetting.ALLOW_SERVER ); 
    } 
 
    private function authenticateUser():void 
    { 
        drmManager.authenticate( drmContentData.serverURL, drmContentData.domain, userName, password ); 
    } 
    private function onAuthenticationError( event:DRMAuthenticationErrorEvent ):void 
    { 
        trace( "Authentication error: " + event.errorID + ", " + event.subErrorID ); 
    } 
 
    private function onAuthenticationComplete( event:DRMAuthenticationCompleteEvent ):void 
    { 
        trace( "Authenticated to: " + event.serverURL + ", domain: " + event.domain ); 
        getVoucher(); 
    } 
    private function onDRMStatus( event:DRMStatusEvent ):void 
    { 
        trace( "DRM Status: " + event.detail); 
        trace("--Voucher allows offline playback = " + event.isAvailableOffline ); 
        trace("--Voucher already cached          = " + event.isLocal ); 
        trace("--Voucher required authentication = " + !event.isAnonymous ); 
    } 
    private function onDRMError( event:DRMErrorEvent ):void 
    { 
        trace( "DRM error event: " + event.errorID + ", " + event.subErrorID + ", " + event.text ); 
    } 
    public function onPlayStatus( info:Object ):void 
    { 
        preloadStream.close(); 
    } 
} 
}