CGlobalModule Class

Article
03/09/2018

Defines the base class for global-level HTTP modules.

Syntax

class CGlobalModule

Methods

The following table lists the methods exposed by the CGlobalModule class.

Name	Description
OnGlobalApplicationPreload	deddc775-1ab0-492c-bda0-b32be5d4f4cc
OnGlobalApplicationResolveModules	Represents the method that will handle a `GlobalApplicationResolveModules` event, which occurs when IIS resolves the registered modules.
OnGlobalApplicationStart	Represents the method that will handle a `GlobalApplicationStart` event, which occurs when IIS starts an application.
OnGlobalApplicationStop	Represents the method that will handle a `GlobalApplicationStop` event, which occurs when IIS shuts down an application.
OnGlobalCacheCleanup	Represents the method that will handle a `GlobalCacheCleanup` event.
OnGlobalCacheOperation	Represents the method that will handle a `GlobalCacheOperation` event, which occurs when IIS performs a cache-related operation.
OnGlobalConfigurationChange	Represents the method that will handle a `GlobalConfigurationChange` event, which occurs when a change is made to a configuration file.
OnGlobalCustomNotification	Represents the method that will handle a `GlobalCustomNotification` event, which occurs when a module raises a user-defined notification.
OnGlobalFileChange	Represents the method that will handle a `GlobalFileChange` event, which occurs when a file within a Web site is changed.
OnGlobalHealthCheck	Represents the method that will handle a `GlobalHealthCheck` event, which occurs when a health-related operation is executed.
OnGlobalPreBeginRequest	Represents the method that will handle a `GlobalPreBeginRequest` event, which occurs before a request enters the pipeline.
OnGlobalRSCAQuery	Represents the method that will handle a `GlobalRSCAQuery` event, which occurs when a Run-Time Status and Control query is executed.
OnGlobalStopListening	Represents the method that will handle a `GlobalStopListening` event, which occurs when IIS stops accepting new requests.
OnGlobalThreadCleanup	Represents the method that will handle a `GlobalThreadCleanup` event, which occurs when IIS returns a thread to the thread pool.
OnGlobalTraceEvent	Represents the method that will handle a `GlobalTraceEvent` event, which occurs when a trace event is raised.
Terminate	Represents the method that IIS calls when a global module has completed processing.

Derived Classes

This class contains no derived classes.

Remarks

The CGlobalModule class is the base class for global-level HTTP modules. Global-level HTTP modules must contain a class that inherits from CGlobalModule. CGlobalModule defines the methods that IIS 7 calls to handle global-level notifications when global-level events occur. An HTTP module can register for specific events by defining a list of notifications in a module's exported RegisterModule function. When a global-level module has finished processing, the module should use the CGlobalModule::Terminate method to remove CGlobalModule instances from memory.

Example

The following code example demonstrates how to create a simple "Hello World" global-level HTTP module. The module defines an exported RegisterModule function that creates an instance of a class that is derived from CGlobalModule. If the class cannot be created, the function exits with an error code; otherwise, the function calls the IHttpModuleRegistrationInfo::SetRequestNotifications method to register for the GL_PRE_BEGIN_REQUEST notification.

When a GL_PRE_BEGIN_REQUEST notification occurs, IIS calls the module's CGlobalModule::OnGlobalPreBeginRequest method to process the notification. The method calls a private method to write an event to the application log of the Event Viewer, and then it returns GL_NOTIFICATION_CONTINUE to notify IIS to continue processing other notifications. When processing is complete, IIS calls the module's CGlobalModule::Terminate method to remove the class from memory.

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

// Create the module's global class.
class MyGlobalModule : public CGlobalModule
{
public:

    // Process a GL_APPLICATION_START notification.
    GLOBAL_NOTIFICATION_STATUS
    OnGlobalPreBeginRequest(
        IN IPreBeginRequestProvider * pProvider
    )
    {
        UNREFERENCED_PARAMETER( pProvider );
        WriteEventViewerLog( "Hello World!" );
        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" );
    }

    ~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;

    // Define a method that writes to the Event Viewer.
    BOOL WriteEventViewerLog(LPCSTR szNotification)
    {
        // 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, 1, 0, &szNotification, 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_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 Global-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

Share via