IHttpServer::GetWorkerProcessSettings Method

 

Retrieves an IWpfSettings interface.

Syntax

virtual HRESULT GetWorkerProcessSettings(  
   IWpfSettings** ppWorkerProcessSettings  
) = 0;  

Parameters

ppWorkerProcessSettings
A dereferenced pointer to an IWpfSettings interface.

Return Value

An HRESULT. Possible values include, but are not limited to, those in the following table.

Value Description
S_OK Indicates that the operation was successful.

Remarks

The GetWorkerProcessSettings method allows developers to retrieve configuration information about the worker process framework through an IWpfSettings interface.

Note

The server controls the lifetime and reference counting for IWpfSettings.

IWpfSettings exposes several methods that you can use to retrieve specific information about the worker process framework. For example, the IWpfSettings::GetDwordProperty method enables you to retrieve the IDLE_TIMEOUT or PERIODIC_RESTART_TIME settings.

Example

The following code example illustrates how to use the GetWorkerProcessSettings method to create an HTTP module that retrieves the version of the common language runtime (CLR) on the server. The module then returns that information to a Web client.

#define _WINSOCKAPI_
#include <windows.h>
#include <sal.h>
#include <httpserv.h>
#include <wpframework.h>

// Create a pointer for the global server interface.
IHttpServer * g_pGlobalInfo = NULL;

// Create the module class.
class MyHttpModule : public CHttpModule
{
public:
    REQUEST_NOTIFICATION_STATUS
    OnBeginRequest(
        IN IHttpContext * pHttpContext,
        IN IHttpEventProvider * pProvider
    )
    {
        UNREFERENCED_PARAMETER( pProvider );

        // Create an HRESULT to receive return values from methods.
        HRESULT hr;

        // Create a pointer to an IWpfSettings class.
        IWpfSettings * pWpfSettings;

        // Retrieve the IWpfSettings class.
        hr = g_pGlobalInfo->GetWorkerProcessSettings(&pWpfSettings);

        // Test for an error.
        if (SUCCEEDED(hr))
        {
            PWSTR pwszSetting = NULL;
            DWORD cchSetting  = 1024;
            PSTR  pszSetting  = NULL;

            // Allocate space for the strings.
            pwszSetting = (PWSTR) pHttpContext->AllocateRequestMemory( cchSetting + 1 );
            pszSetting  = (PSTR)  pHttpContext->AllocateRequestMemory( cchSetting + 1 );

            // Test for an error.
            if ((NULL == pwszSetting) || (NULL == pszSetting))
            {
                // Set the error status.
                hr = HRESULT_FROM_WIN32(ERROR_NOT_ENOUGH_MEMORY);
                pProvider->SetErrorStatus( hr );
                // End additional processing.
                return RQ_NOTIFICATION_FINISH_REQUEST;
            }

            // Retrieve the CLR version.
            hr = pWpfSettings->GetStringProperty(CLR_VERSION,pwszSetting,&cchSetting);

            // Test for an error.
            if (SUCCEEDED(hr))
            {
                // Convert the WCHAR string to a CHAR string.
                wcstombs(pszSetting,pwszSetting,cchSetting);
                
                // Clear the existing response.
                pHttpContext->GetResponse()->Clear();
                // Set the MIME type to plain text.
                pHttpContext->GetResponse()->SetHeader(
                    HttpHeaderContentType,"text/plain",
                    (USHORT)strlen("text/plain"),TRUE);
                
                // Return the CLR version to the client.
                WriteResponseMessage(pHttpContext,
                    "CLR Version: ",pszSetting);
                
                // End additional processing.
                return RQ_NOTIFICATION_FINISH_REQUEST;
            }
        }

        // Return processing to the pipeline.
        return RQ_NOTIFICATION_CONTINUE;
    }

private:

    // Create a utility method that inserts a name/value pair into the response.
    HRESULT WriteResponseMessage(
        IHttpContext * pHttpContext,
        PCSTR pszName,
        PCSTR pszValue
    )
    {
        // Create an HRESULT to receive return values from methods.
        HRESULT hr;
        
        // Create a data chunk.
        HTTP_DATA_CHUNK dataChunk;
        // Set the chunk to a chunk in memory.
        dataChunk.DataChunkType = HttpDataChunkFromMemory;
        // Buffer for bytes written of data chunk.
        DWORD cbSent;

        // Set the chunk to the first buffer.
        dataChunk.FromMemory.pBuffer =
            (PVOID) pszName;
        // Set the chunk size to the first buffer size.
        dataChunk.FromMemory.BufferLength =
            (USHORT) strlen(pszName);
        // Insert the data chunk into the response.
        hr = pHttpContext->GetResponse()->WriteEntityChunks(
            &dataChunk,1,FALSE,TRUE,&cbSent);
        // Test for an error.
        if (FAILED(hr))
        {
            // Return the error status.
            return hr;
        }

        // Set the chunk to the second buffer.
        dataChunk.FromMemory.pBuffer =
            (PVOID) pszValue;
        // Set the chunk size to the second buffer size.
        dataChunk.FromMemory.BufferLength =
            (USHORT) strlen(pszValue);
        // Insert the data chunk into the response.
        hr = pHttpContext->GetResponse()->WriteEntityChunks(
            &dataChunk,1,FALSE,TRUE,&cbSent);
        // Test for an error.
        if (FAILED(hr))
        {
            // Return the error status.
            return hr;
        }

        // Return a success status.
        return S_OK;
    }
};

// Create the module's class factory.
class MyHttpModuleFactory : public IHttpModuleFactory
{
public:
    HRESULT
    GetHttpModule(
        OUT CHttpModule ** ppModule, 
        IN IModuleAllocator * pAllocator
    )
    {
        UNREFERENCED_PARAMETER( pAllocator );

        // Create a new instance.
        MyHttpModule * pModule = new MyHttpModule;

        // Test for an error.
        if (!pModule)
        {
            // Return an error if the factory cannot create the instance.
            return HRESULT_FROM_WIN32( ERROR_NOT_ENOUGH_MEMORY );
        }
        else
        {
            // Return a pointer to the module.
            *ppModule = pModule;
            pModule = NULL;
            // Return a success status.
            return S_OK;
        }            
    }

    void Terminate()
    {
        // Remove the class from memory.
        delete this;
    }
};

// Create the module's exported registration function.
HRESULT
__stdcall
RegisterModule(
    DWORD dwServerVersion,
    IHttpModuleRegistrationInfo * pModuleInfo,
    IHttpServer * pGlobalInfo
)
{
    UNREFERENCED_PARAMETER( dwServerVersion );

    // Store the pointer for the global server interface.
    g_pGlobalInfo = pGlobalInfo;

    // Set the request notifications and exit.
    return pModuleInfo->SetRequestNotifications(
        new MyHttpModuleFactory,
        RQ_BEGIN_REQUEST,
        0
    );
}

Your module must export the RegisterModule function. You can export this function by creating a module definition (.def) file for your project, or you can compile the module by using the /EXPORT:RegisterModule switch. For more information, see Walkthrough: Creating a Request-Level HTTP Module By Using Native Code.

You can optionally compile the code by using the __stdcall (/Gz) calling convention instead of explicitly declaring the calling convention for each function.

Requirements

Type Description
Client - IIS 7.0 on Windows Vista
- IIS 7.5 on Windows 7
- IIS 8.0 on Windows 8
- IIS 10.0 on Windows 10
Server - IIS 7.0 on Windows Server 2008
- IIS 7.5 on Windows Server 2008 R2
- IIS 8.0 on Windows Server 2012
- IIS 8.5 on Windows Server 2012 R2
- IIS 10.0 on Windows Server 2016 Technical Preview
Product - IIS 7.0, IIS 7.5, IIS 8.0, IIS 8.5, IIS 10.0
- IIS Express 7.5, IIS Express 8.0, IIS Express 10.0
Header Httpserv.h

See Also

IHttpServer Interface
IWpfSettings Interface