Universal Messaging C++: Peer to Peer Stream-based Server Services

Universal Messaging Peer to Peer Stream-based Services communicate via input and output streams on both the Stream-based Client and the Stream-based Server Service.

Anything written to the output stream of the Stream-based Service Client is received via the input stream of the Stream-based Server Service and vice versa.

Firstly, in the same way that Publish/Subscribe and Message Queues use an RNAME, the P2P API also requires one to connect to the Realm. The code snippet below shows how this is achieved:

std::string[] RNAME=({"nsp://127.0.0.1:9000"});
nSessionAttributes *nsa = new nSessionAttributes(RNAME);
nServiceFactory *factory = new nServiceFactory( nsa );

The nServiceFactory object establishes a connection with the Universal Messaging Realm, and is the factory object from which we can construct our Stream-based Server Service:

nServerService *Server = factory->createStreamService( "example", "Example Stream-based Service" );
while ( true ) {
nEventService *serv = (nEventService) server->accept();
Stream *inputstream = serv->getInputStream();
Stream *outputstream = serv->getOutputStream();
// your logic goes here....
// e.g. query a database, make a connection, send an email, etc.
printf("Got connection %s",(serv->getServiceInfo())->getName());
}

The code snippet above shows how to create an Stream-based Server Service and wait for Client connections. Developers are free to decide how the Server Service should respond once a Client connects to the Server Service.

When a connection is made to the Stream-based Server Service, the Service has an Input Stream (which can be read from), and an Output Stream (which can be written to).

The Server Service's Input Stream represents data coming from the client. The following code snippet shows how to obtain this Input Stream:

Stream *iStream = serv->getInputStream();

The Server Service's Output Stream represents data going to the client. The following code snippet shows how to obtain this Output Stream:

Stream *oStream = serv->getOutputStream();

The code example "P2P Shell" shows how to implement a Stream-based Server Service and Client:

For more information on Universal Messaging Peer to Peer Services please see the API documentation.