SockIt · Full Tutorial

On either clients or servers, we can register callbacks to be invoked when any data is received on the connection. Assuming we already have a TCP (or UDP) server myServer listening on some port, we can log all data received with:

	myServer.addEventListener('data', function(event) {
                var data = event.read();
		console.log("Received: " + data);
	});

Likewise, functions that handle 'data' functions should receive an event object, with which we can read the data received, reply to any data received, or get information about the remote endpoint. For instance, to have myServer also reply to every message received with an acknowledgement, we simply change the previous code to the following:

	myServer.addEventListener('data', function(event) {
                var message = event.read();
		console.log("Received: " + message);
		event.send("Got your message!");
		
	});

On either clients or servers, we can register a callback to be invoked when an error occurs in an object. For instance, suppose we have some client, myErrorProneClient, and would like to log any errors on that object to the browser console. We can do so with the following:

	myErrorProneClient.addEventListener('error', function(message) {
		console.log("Error: " + message);
		// Error handle
	});

When an error occurs, an event is fired which contains the error message as a parameter, so that it can be used for debugging as shown above.

Since all I/O is performed asynchronously, calling shutdown on a server or client may not immediately complete, but will be executed once any data waiting to be sent has been sent. Suppose we want to be notified when some server, say myOldServer, has completely shutdown and closed its socket. We can do this by registering a callback on a 'close' event, which provides no parameters, as shown below:

	myOldServer.addEventListener('close', function() {
		console.log("My old server finally shutdown!");
		// Cleanup
	});

	server.addEventListener('resolve', function() {
		console.log("Remote endpoint successfully resolved!");
		// Do stuff
	});

	server.addEventListener('open', function() {
		console.log("Server is now listening!");
		// Do stuff
	});

For TCP clients and servers we can register a callback to occur whenever the client or server has disconnect from the remote host:

	myTcpClientOrServer.addEventListener('disconnect', function(message) {
		console.log("My TCP object has been disconnected! Error message: " + message);
		// Error handle
	});

Thus, when a TCP client or server has disconnected from some remote host, an event is fired which contains the error message as a parameter, so that it can be used for debugging as shown above.

For TCP clients or servers we can register a callback to occur whenever the client or server has connected to a remote host:

	myTcpClientOrServer.addEventListener('connect', function() {
		console.log("My TCP client or server has been connected!");
		// Do stuff
	});

When a TCP client or server has connected to some remote host, an event is fired which contain no parameters.