Configuring Caching

  • Articolo

Enabling content caching on publishing points allows cache proxy servers to store content locally, reducing the bandwidth and resource usage on the main server. Content caching requires a cache proxy plug-in. Windows Media Services does not include a cache proxy plug-in, but you can make your own. For more information, see Creating Cache Proxy Plug-ins. You can use the AllowContentCaching property on the IWMSOnDemandPublishingPoint interface to enable caching. This is illustrated by the following examples.

Visual Basic .NET Example

Imports Microsoft.WindowsMediaServices.Interop
Imports System.Runtime.InteropServices

' Declare variables.
Dim Server As WMSServer
Dim ODPubPoint As IWMSOnDemandPublishingPoint

Try
    ' Create the WMSServer object.
    Server = New WMSServer()

    ' Retrieve the first publishing point.
    ODPubPoint = Server.PublishingPoints.Item(0)

    ' Set this publishing point to allow cache proxy
    ' servers to cache content.
    ODPubPoint.AllowContentCaching = True

Catch errCom As COMException
    ' TODO: Handle COM exceptions.
Catch err As Exception
    ' TODO: Exception handler goes here.
Finally
    ' TODO: Clean-up code goes here.
End Try

C# Example

using Microsoft.WindowsMediaServices.Interop;
using System.Runtime.InteropServices;

// Declare variables.
WMSServer Server;
IWMSOnDemandPublishingPoint ODPubPoint;

try 
{
    // Create the WMSServer object.
    Server = new WMSServerClass();

    // Retrieve the first publishing point.
    ODPubPoint = (IWMSOnDemandPublishingPoint)Server.PublishingPoints[0];

     // Set this publishing point to allow cache proxy
     // servers to cache content.
     ODPubPoint.AllowContentCaching = true;
}
catch (COMException comExc)
{
    // TODO: Handle COM exceptions.
}
catch (Exception exc)
{
    // TODO: Exception handler goes here.
}
finally
{
    // TODO: Clean-up code goes here.
}

C++ Example

#include <windows.h>
#include <atlbase.h>    // Includes CComVariant.
#include "wmsserver.h"

// Declare variables and interfaces.
IWMSServer                  *pServer;
IWMSPublishingPoints        *pPubPoints;
IWMSPublishingPoint         *pPubPoint;
IWMSOnDemandPublishingPoint *pODPubPoint;

HRESULT         hr;
CComVariant     varIndex;
long            lCount;

// Initialize the COM library and retrieve a pointer
// to an IWMSServer interface.
hr = CoInitialize(NULL);
hr = CoCreateInstance(CLSID_WMSServer,
                      NULL,
                      CLSCTX_ALL,
                      IID_IWMSServer,
                      (void **)&pServer);
if (FAILED(hr)) goto EXIT;

// Retrieve a pointer to the IWMSPublishingPoints interface.
hr = pServer->get_PublishingPoints(&pPubPoints);
if (FAILED(hr)) goto EXIT;

// Retrieve the total count of publishing points.
hr = pPubPoints->get_Count(&lCount);
if (FAILED(hr)) goto EXIT;

// Retrieve a pointer to the first publishing point.
varIndex = 0;
hr = pPubPoints->get_Item(varIndex, &pPubPoint);
if (FAILED(hr)) goto EXIT;

// Query a pointer to an IWMSOnDemandPublishingPoint interface.
hr = pPubPoint->QueryInterface(IID_IWMSOnDemandPublishingPoint,
                              (void **)&pODPubPoint);
if (FAILED(hr)) goto EXIT;

// Set this publishing point to allow cache proxy
// servers to cache its contents.
hr = pODPubPoint->put_AllowContentCaching(VARIANT_TRUE);
if (FAILED(hr)) goto EXIT;

EXIT:
    // TODO: Release temporary COM objects and uninitialize COM.

See Also (General)

See Also (Visual Basic .NET)

See Also (C#)

See Also (C++)