IGlobalThreadCleanupProvider::GetApplication

Article
05/24/2022

Retrieves an IHttpApplication interface.

Syntax

virtual IHttpApplication* GetApplication(  
   VOID  
) = 0;

Parameters

This method takes no parameters.

Return Value

A pointer to an IHttpApplication interface.

Remarks

Developers can use the GetApplication method to retrieve an IHttpApplication interface, which they can then use to retrieve configuration information for an application.

Example

The following code example demonstrates how to create an HTTP module that performs the following tasks:

Registers for the GL_THREAD_CLEANUP notification.
Creates a CGlobalModule class that contains an OnGlobalThreadCleanup method. This method performs the following tasks:
1. Retrieves an IHttpApplication interface by using the GetApplication method.
2. Retrieves the application identifier of the current context's application by using the IHttpApplication::GetApplicationId method.
3. Writes the application identifier information as an event to the application log of the Event Viewer.
Removes the CGlobalModule class from memory and then exits.

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

// Create the module's global class.
class MyGlobalModule : public CGlobalModule
{
public:
    GLOBAL_NOTIFICATION_STATUS
    OnGlobalThreadCleanup(
        IN IGlobalThreadCleanupProvider * pProvider
    )
    {
        UNREFERENCED_PARAMETER( pProvider );
        
        // Retrieve a pointer to the IHttpApplication class.
        IHttpApplication * pHttpApplication =
            pProvider->GetApplication();

        // Retrieve a pointer to the application configuration path.
        PCWSTR pwszApplicationId = pHttpApplication->GetApplicationId();

        // Test for an error.
        if (m_pHttpContext!=NULL)
        {
            // Allocate space for the user name.
            char * pszBuffer = (char*) m_pHttpContext->AllocateRequestMemory(
                (DWORD) wcslen(pwszApplicationId)+1 );
        
            // Test for an error.
            if (pszBuffer!=NULL)
            {
                // Return the user information to the Web client.
                wcstombs(pszBuffer,pwszApplicationId,wcslen(pwszApplicationId));
                // Create an array of strings.
                LPCSTR szBuffer[3] = {"OnGlobalThreadCleanup",
                    "Application ID:",pszBuffer};
                // Write the strings to the Event Viewer.
                WriteEventViewerLog(szBuffer,3);
            }
        }

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

    GLOBAL_NOTIFICATION_STATUS
    OnGlobalPreBeginRequest(
        IN IPreBeginRequestProvider * pProvider
    )
    {
        UNREFERENCED_PARAMETER( pProvider );
        // Retrieve a pointer to the context.
        m_pHttpContext = pProvider->GetHttpContext();
        // Return processing to the pipeline.
        return GL_NOTIFICATION_CONTINUE;
    }

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

    MyGlobalModule()
    {
        // Open a handle to the Event Viewer.
        m_hEventLog = RegisterEventSource( NULL,"IISADMIN" );
        // Initialize the context pointer to NULL.
        m_pHttpContext = NULL;
    }

    ~MyGlobalModule()
    {
        // Test whether the handle for the Event Viewer is open.
        if (NULL != m_hEventLog)
        {
            // Close the handle to the Event Viewer.
            DeregisterEventSource( m_hEventLog );
            m_hEventLog = NULL;
        }
    }

private:

    // Create a handle for the event viewer.
    HANDLE m_hEventLog;
    // Create a pointer for the module context.
    IHttpContext * m_pHttpContext;

    // Define a method that writes to the Event Viewer.
    BOOL WriteEventViewerLog(LPCSTR * lpStrings, WORD wNumStrings)
    {
        // Test whether the handle for the Event Viewer is open.
        if (NULL != m_hEventLog)
        {
            // Write any strings to the Event Viewer and return.
            return ReportEvent(
                m_hEventLog, EVENTLOG_INFORMATION_TYPE,
                0, 0, NULL, wNumStrings, 0, lpStrings, NULL );
        }
        return FALSE;
    }
};

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

    // Create an instance of the global module class.
    MyGlobalModule * pGlobalModule = new MyGlobalModule;
    // Test for an error.
    if (NULL == pGlobalModule)
    {
        return HRESULT_FROM_WIN32(ERROR_NOT_ENOUGH_MEMORY);
    }
    // Set the global notifications and exit.
    return pModuleInfo->SetGlobalNotifications(
        pGlobalModule, GL_THREAD_CLEANUP | GL_PRE_BEGIN_REQUEST );
}

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
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

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