Websocket Server

A minimal Websockets Server in Python with no external dependencies.

• Works with Python2 and Python3
• Clean simple API
• Multiple clients
• No dependencies

Notice that this implementation does not support the more advanced features like SSL etc. The project is focused mainly on making it easy to run a websocket server for prototyping, testing or for making a GUI for your application.

Usage

You can get a feel of how to use the websocket server by running

python server.py

Then just open client.html in your browser and you should be able to send and receive messages.

Using in your project

You can use the project in three ways.

1. Copy/paste the websocket_server.py file in your project and use it directly
2. pip install git+https://github.com/Pithikos/python-websocket-server (latest code)
3. pip install websocket-server (might not be up-to-date)

For coding details have a look at the server.py example and the API.

API

The API is simply methods and properties of the WebsocketServer class.

WebsocketServer

The WebsocketServer can be initialized with the below parameters.

port - The port clients will need to connect to.

host - By default the 127.0.0.1 is used which allows connections only from the current machine. If you wish to allow all network machines to connect, you need to pass 0.0.0.0 as hostname.

loglevel - logging level to print. By default WARNING is used. You can use logging.DEBUG or logging.INFO for more verbose output.

Properties

Property	Description
clients	A list of client

Methods

Method	Description	Takes	Gives
set_fn_new_client()	Sets a callback function that will be called for every new client connecting to us	function	None
set_fn_client_left()	Sets a callback function that will be called for every client disconnecting from us	function	None
set_fn_message_received()	Sets a callback function that will be called when a client sends a message	function	None
send_message()	Sends a message to a specific client. The message is a simple string.	client, message	None
send_message_to_all()	Sends a message to all connected clients. The message is a simple string.	message	None

Callback functions

Set by	Description	Parameters
set_fn_new_client()	Called for every new client connecting to us	client, server
set_fn_client_left()	Called for every client disconnecting from us	client, server
set_fn_message_received()	Called when a client sends a message	client, server, message

The client passed to the callback is the client that left, sent the message, etc. The server might not have any use to use. However it is passed in case you want to send messages to clients.

Example:

import logging
from websocket_server import WebsocketServer

def new_client(client, server):
	server.send_message_to_all("Hey all, a new client has joined us")

server = WebsocketServer(13254, host='127.0.0.1', loglevel=logging.INFO)
server.set_fn_new_client(new_client)
server.run_forever()

Client

Client is just a dictionary passed along methods.

{
	'id'      : client_id,
	'handler' : client_handler,
	'address' : (addr, port)
}