node-server

A generic server with client and room management. The server is usable for UDP, TCP, HTTP/S, or WS/S.

Example

Create a TCP server on localhost:777 and handle client events. Note that the Server class already manages clients in a ClientManager and has some default connection and message handlers built in.

let tcpServer = new TcpServer({port:777});
tcpServer.on('connect', function(client){
   client.on('message', function(message){
       console.log(message);
   });
   client.on('disconnect', function(){
       console.log(`Client ${client.id} disconnected`);
   });
});
tcpServer.start();

Description

node-server provides classes for a WebSocket, TCP, UDP, or HTTP server. Each server type extends from a base server that has an abstract communication layer. A server handles incoming connections with a server listener. A server listener is an object that emits connection events it receives on some port using some protocol. node-server comes with a server, server listener, client object, client manager, room object, and room manager. You can begin adding routing and logic to the server immediately.

Classes

ServerListener

ServerListener is an EventEmitter that listens for connections on a socket using some protocol. When new connections are detected, ServerListener creates the appropriate Client object and emits the connect event with a client object. node-server provides these implemented classes:

• TcpServerListener
• UdpServerListener
• WebSocketServerListener
• HttpServerListener

Server

Server is an EventEmitter that creates some type of ServerListener depending on the desired protocol. When a ServerListener emits the connect event with a client, Server adds that client to its ClientManager and attaches some default handlers to listen for data and other events. Server also has a RoomManager which can be used to group clients into a Room.

Client

Client is an EventEmitter that wraps a socket. It is created by a ServerListener when a connection is detected. It always emits the following events, regardless of what kind of protocol it is

• message
• disconnect
• reconnect
• error
• maxError
• ping
• pong

Note that there is no connect event because you cannot have a Client before a connection; only Server/ServerListener emits connect events. The message event always emits some kind of Message object, which could be the default Message or one you create yourself that extends Message. A Message is the data from the client wrapped in an object - this could be JSON, XML, or any kind of data. Message has built-in JSON processing functions, but can be extended to do anything desirable.

ClientManager

ClientManager manages Clients. It can limit the amount of clients, keeps track of client counts, and can add a client to a blacklist.

Room

Room is a small extension of a ClientManager. A room adds ownership, password security, and privitization (making it inivisible). Rooms are particularly useful for reducing overhead. If you have some clients that want to communicate between each other - such as a chat room or a game - placing them in a Room means they do not have to talk directly to the Server, and the Server does not have to figure out what Room they are in.

RoomManager

RoomManager manages a listing of Room objects.

Message

Message is an object used to send data to clients and to receive data from clients. Message is generic enough that it can be extended to support any messaging protocol. Its default implementation serializes an object of data to a JSON string to send to a client, and deserializes a string of data to a JSON object when receiving data from a client. If your messaging protocol is not JSON (say, XML) you would need to write a class such as XmlMessage and override the serialize and deserialize functions. Then, you can pass your XmlMessage constructor to your Server instance, and all messages would now be serialized and deserialized to and from XML.

Message also has an optional buffer that should be used for TCP and UDP servers. Clients that communicate on these protocols should always send some "end character" to indicate that they have completed sending a message, such as \n or <EOF> or anything else. This is unlike Web Socket and HTTP protocols.

Messages have the following properties

• cmd: the command to run
• data: the data to use with the cmd
• msg: a textual message, usually for error messages
• status: 0 for error, 1 for ok