IScriptMapInfo::GetAllowedVerbs Method

Retrieves the list of allowed verbs for a script map.

Syntax

virtual PCSTR GetAllowedVerbs(  
   VOID  
) const = 0;  

Parameters

This method takes no parameters.

Return Value

A pointer to a string that contains the list of allowed verbs.

Remarks

Developers can use the GetAllowedVerbs method to retrieve the list of allowed HTTP verbs for a page handler. For example, if you request a static HTML page that is hosted by an IIS 7 Web site, the static file handler may be configured to allow all HTTP verbs. However, if you if you request a dynamic ASP page that is hosted by the same IIS 7 Web site, the ASP page handler may be configured to allow only the GET and POST verbs.

Note

Web administrators can configure the list of allowed verbs by using IIS Manager.

Example

The following code example demonstrates how to create an HTTP module that retrieves a pointer to an IHttpContext::IScriptMapInfo interface. The example then uses the GetAllowedVerbs method to retrieve the list of verbs that are allowed for the script map. The module returns the list of allowed verbs to a Web client and then exits.

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

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

        // Retrieve the IScriptMapInfo interface.
        IScriptMapInfo * pScriptMapInfo = pHttpContext->GetScriptMap();

        // Test for an error.
        if (NULL != pScriptMapInfo)
        {
            // Buffer to store the allowed verbs.
            PCSTR pszAllowedVerbs;
            // Retrieve the allowed verbs.
            pszAllowedVerbs = pScriptMapInfo->GetAllowedVerbs();
            // Test for an error.
            if (pszAllowedVerbs != NULL)
            {
                // 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 list of allowed verbs to the client.
                WriteResponseMessage(pHttpContext,
                    "Allowed Verbs: ", pszAllowedVerbs);
                // 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,
        0,
        RQ_MAP_REQUEST_HANDLER
    );
}

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

See Also

IScriptMapInfo Interface