IHttpContext::GetUser Method

 

Retrieves the user information container for the current context.

Syntax

virtual IHttpUser* GetUser(  
   VOID  
) const = 0;  

Parameters

This method takes no parameters.

Return Value

A pointer to an IHttpUser interface.

Remarks

The GetUser method returns an IHttpUser interface, which contains several methods for retrieving security-related information for the current request. For example, you can use the IHttpUser::GetUserName and IHttpUser::GetPassword methods to retrieve the user credentials for an authenticated user.

Note

The HTTP context object owns the lifetime of the IHttpUser interface that is returned by the GetUser method. Therefore, you do not free this pointer when you write HTTP modules.

Example

The following code example demonstrates how to use the GetUser method to create an HTTP module that retrieves an IHttpUser interface. The example then uses the IHttpUser::GetUserName method to retrieve the current user name. If the Web site is using anonymous authentication, the user name will be blank, and the HTTP module will return a message that the Web site is using anonymous authentication. Otherwise, the HTTP module will return the current user name to a Web client.

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

// Create the module class.
class MyHttpModule : public CHttpModule
{
public:

    REQUEST_NOTIFICATION_STATUS
    OnSendResponse(
        IN IHttpContext * pHttpContext,
        IN ISendResponseProvider * pProvider
    )
    {
        UNREFERENCED_PARAMETER( pProvider );

        // Clear the existing response.
        pHttpContext->GetResponse()->Clear();

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

        // Create pointers for the user name buffers.
        PCWSTR pwszUserName;
        char*  pszUserName;

        // Retrieve the IHttpUser interface.
        IHttpUser * pHttpUser = pHttpContext->GetUser();

        // Test for an error.
        if (pHttpUser != NULL)
        {
            // Retrieve the user name.
            pwszUserName = pHttpUser->GetUserName();
            // Test for an error.
            if (pwszUserName!=NULL)
            {
                // Test for anonymous user.
                if (0==wcslen(pwszUserName))
                {
                    // Return the anonymous user information to the web client.
                    WriteResponseMessage(pHttpContext,
                        "User name: ","ANONYMOUS");
                }
                else
                {
                    // Allocate space for the user name.
                    pszUserName = (char*) pHttpContext->AllocateRequestMemory( (DWORD) wcslen(pwszUserName)+1 );
                    // Test for an error.
                    if (pszUserName==NULL)
                    {
                        // Set the error status.
                        hr = HRESULT_FROM_WIN32(ERROR_NOT_ENOUGH_MEMORY);
                        pProvider->SetErrorStatus( hr );
                    }
                    else
                    {
                        // Return the user information to the Web client.
                        wcstombs(pszUserName,pwszUserName,wcslen(pwszUserName));
                        WriteResponseMessage(pHttpContext,
                            "User name: ",pszUserName);
                    }
                    // 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 );
    UNREFERENCED_PARAMETER( pGlobalInfo );

    // Set the request notifications and exit.
    return pModuleInfo->SetRequestNotifications(
        new MyHttpModuleFactory,
        RQ_SEND_RESPONSE,
        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 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

IHttpContext Interface
IHttpUser Interface