Provide a simple interface for objects handling network requests on a server thread. More...

#include <serverclient.h>

Public Member Functions
virtual IServerClient *	NewInstance (SOCKET iSocket, uint32_t iHost, uint16_t iPort)=0
	Requests a clone of the current server client object to handle an incoming connection on the given socket.
virtual bool	ProcessMessage (const std::vector< unsigned char > &vecbMessage)=0
	Called when a new message has been received from the client and should be processed by the server.
virtual void	Destroy ()=0
	Indicates that the server client object should delete itself.

Detailed Description

Provide a simple interface for objects handling network requests on a server thread.

When a CServer detects an incoming connection, it creates a new thread and passes control of that thread to an IServerClient to communicate with the incoming client. By implementing IServerClient, a Sleipnir user can quickly and easily create multithreaded network servers.

Sleipnir servers always assume that TCP/IP messages are passed preceded by a four-byte unsigned integer indicating the size of the message. For example, to send the string, "Hello, world!" to a CServer object, a client should send the integer 13 to the server, followed by the 13 bytes of the message (assuming ASCII encoding, of course). It is not necessary for Sleipnir servers to respond to their clients in the same manner - this is left up to the implementation of ProcessMessage - but it is good practice and can greatly simplify TCP/IP communication.

For example, to create an echo server client, one might implement:

 class CEchoServerClient : public IServerClient {
 public:
   SOCKET  m_iSocket;
 
   CEchoServerClient( SOCKET iSocket ) : m_iSocket(iSocket) { }
 
   IServerClient* NewInstance( SOCKET iSocket, uint32_t iHost, uint16_t iPort ) {
     return new CEchoServerClient( iSocket ); }
 
   void Destroy( ) {
     delete this; }
 
   bool ProcessMessage( const vector<unsigned char>& vecbMessage ) {
     size_t    i;
     uint32_t  iSize;
 
     iSize = vecbMessage.size( );
     send( m_iSocket, &iSize, sizeof(iSize), 0 );
     for( i = 0; i < vecbMessage.size( ); ++i )
       if( vecbMessage[ i ] == EOF )
         return false;
       else
         send( m_iSocket, &vecbMessage[ i ], 1, 0 );
 
     return true; }
 }

See CServer for an example server setup using this client object.

Remarks:: CServer will call IServerClient::NewInstance for each new incoming request, creating a new client object to handle that thread. When the connection is closed by IServerClient::ProcessMessage returning false, the server will call IServerClient::Destroy to clean up that object. The original server client object (ESC in the example above) is only used to create additional new instances.

Definition at line 84 of file serverclient.h.

Member Function Documentation

virtual void Sleipnir::IServerClient::Destroy ( ) [pure virtual]

Indicates that the server client object should delete itself.

Remarks:: Provided so that delete doesn't need to be called directly on an opaque interface.

virtual IServerClient* Sleipnir::IServerClient::NewInstance	(	SOCKET	iSocket,
		uint32_t	iHost,
		uint16_t	iPort
	)		`[pure virtual]`

Requests a clone of the current server client object to handle an incoming connection on the given socket.

Parameters:

iSocket	Socket to be used for communication with the incoming request.
iHost	Host byte-ordered encoding of the incoming client's IP address.
iPort	Host byte-ordered encoding of the incoming client's IP port.

Returns:: A clone of the current object configured to handle the given incoming connection request.

CServer calls NewInstance whenever an incoming connection request is detected. The returned new server client object should be configured to store iSocket and, optionally, the host and port information so as to communicate with the new client during ProcessMessage.

Remarks:: iHost and iPort are ntoh decoded versions of sin_addr.s_addr and sin_port, respectively.

virtual bool Sleipnir::IServerClient::ProcessMessage ( const std::vector< unsigned char > & vecbMessage ) [pure virtual]

Called when a new message has been received from the client and should be processed by the server.

Parameters:

vecbMessage Contents of the message sent by the clients (without the preceding byte size indicator).

Returns:: True if the message was handled and the server should continue the connection, false to close the connection.

Remarks:: Sleipnir puts no constraints on the contents of messages passed to and from network servers - the bytes in vecbMessage can be ASCII text or any other arbitrary data.

The documentation for this class was generated from the following file:

src/serverclient.h

Public Member Functions

Detailed Description

Member Function Documentation