eight-protocol

NodeJS socket communication lib over a protocol with 8 bytes descriptor

Objective

When you test a simple socket communication, in the more of times everything works fine, but when your project grow up, after publish and test with remote and bad connections, you will get some problems with truncated messages or messages with extra data (part of the next message). It is normal. You will need create a protocol to handle that situation, maybe implement a header or a terminator (bad ideia), maybe you are already frustated with that notice.

The eight protocol is an implementation plug-and-play of a transparent protocol for handle those situations for you, and the most important: it does not change your code too much.

The message transfered is distributed in two sections:

Header

A Key/Value object to identify the message (parameter: transaction, id, token, type, etc...), you can set any object.

Body

Binary Data, you can pass anything here

Quick Start

Server

var protocol = require("eight-protocol");
var server =  new protocol.server(7890);

server.on('server_listening', function(){
	console.log("Server ir up! Now waiting for connections");
});

server.on('client_connected', function(socketClient){
	console.log("NEW CLIENT CONNECTED!");
});

server.on("data", function(socketClient, header, dataBuffer){
	console.log("MESSAGE RECEIVED!",header,dataBuffer.toString());
});

server.on('client_close', function(socketClient){
	console.log("CLIENT DISCONNECTED!");
});

Client

var protocol = require("eight-protocol");
var client = new protocol.client("0.0.0.0", 7890);

client.on("client_connected", function(socket){
	console.log("Connected on the server");
	//Send message
	protocol.send(socket, {transaction : "GREETINGS"}, "Hello World!");
})

API

protocol.send(socket, header, buffer, [callback]); Send a message for the given socket.

• Socket - The nodejs socket from the new connection callback
• Header - Key/Value object, it will be converted internally to a JSON String
• Buffer - Your data, must be a buffer or String
• Callback (optional) - A callback function with and error parameter if it have

Server

new protocol.server(port, [debug]); Instantiate a new server and try to start listen imediatly

• port - must be an integer, it will be the respective TCP port to listen
• debug (optional) - must be a boolean, if true, the lib will print some informations like message size, incoming bytes, outcoming bytes, etc.

Events

Event name	Description
client_connected	callback(clientSocket : Socket) - When a new client connection is established on the server
client_close	callback(clientSocket : Socket, hadError : Boolean)When a client disconnect from the server
client_end	callback(clientSocket : Socket) - When a client connection ends
client_timeout	callback(clientSocket : Socket) - When a client timeout
client_error	callback(clientSocket : Socket, error : Object) - When client socket gives an error
data	callback(clientSocket : Socket, header : Object , dataBuffer : Buffer) - When receive a message from a client
server_error	callback(error : Object) - When the server gives an error
server_listening	callback() - When the server start listening

Client

new protocol.client(address, port, timeout, debug)

Instantiate a new client and try connect imediatly

• Address - Must me and string, should be the remote ip address
• port - must be an integer, it will be the respective TCP port to listen
• timeout (optional) - must be an integer, will set the socket timeout (see more at https://nodejs.org/api/net.html#net_socket_settimeout_timeout_callback)
• debug (optional) - must be a boolean, if true, the lib will print some informations like message size, incoming bytes, outcoming bytes, etc.

Events

Event name	Description
client_connected	callback(clientSocket : Socket) - When connection is established on the server
client_close	callback(clientSocket : Socket, hadError : Boolean) When disconnect from the server
client_end	callback(clientSocket : Socket) - When connection ends
client_timeout	callback(clientSocket : Socket) - When connection timedout
client_error	callback(clientSocket : Socket, error : Object) - When client socket gives an error
data	callback(clientSocket : Socket, header : Object , dataBuffer : Buffer) - When receive a message from a Server