Balamurugan Kandan balamuruganky

Full socket.io client and server example

Last updated: 2021-02-21, tested with socket.io v3.1.1

This is the simplest implementation you will find for a client/server WebSockets architecture using socket.io.

To see a full explanation, read my answer on SO here: https://stackoverflow.com/a/24232050/778272.

If you're looking for examples using frameworks, check these links:

Install all the following. On Window, install Xming. On Ubuntu bash, use sudo apt install to install ssh xauth xorg.

sudo apt install ssh xauth xorg

If you are not interested in the technical details and only want to get Listen to work:

If you are running Debian, RedHat, or another similar Linux distribution, run the following in a terminal:

echo fs.inotify.max_user_watches=524288 | sudo tee -a /etc/sysctl.conf && sudo sysctl -p

https://github.com/djvirgen/virgen-acl
"Simple in-memory ACL for node.js apps. Supports arbitrary roles and resources, including role/resource detection using a simple interface. Additionally supports custom assertions for more complex rules."
Comments: "Simple and elegant, create your own checks. No middleware?"

	import asyncio
	import logging
	# XXX: REMOVE THIS LINE IN PRODUCTION!
	logging.basicConfig(format='%(asctime)s %(lineno)d %(levelname)s:%(message)s', level=logging.DEBUG)
	logger = logging.getLogger(__name__)

	# Connected client records
	clients = dict()

	### KERNEL TUNING ###

	# Increase size of file handles and inode cache
	fs.file-max = 2097152

	# Do less swapping
	vm.swappiness = 10
	vm.dirty_ratio = 60
	vm.dirty_background_ratio = 2

	import asyncio
	import fcntl
	import os
	from functools import partial


	class AsyncPIPE:
	@staticmethod
	def create_pipe():
	read_fd, write_fd = os.pipe()

	# See official docs at https://dash.plotly.com
	# pip install dash pandas

	from dash import Dash, dcc, html, Input, Output
	import plotly.express as px

	import pandas as pd

	df = pd.read_csv('https://raw.githubusercontent.com/plotly/datasets/master/gapminderDataFiveYear.csv')

	//
	// Simple listener.c program for UDP multicast
	//
	// Adapted from:
	// http://ntrg.cs.tcd.ie/undergrad/4ba2/multicast/antony/example.html
	//
	// Changes:
	// * Compiles for Windows as well as Linux
	// * Takes the port and group on the command line
	//

	/*
	Settings (the ones below are examples: choose what is best for your data)
	set lag to 5; # lag 5 for the smoothing functions
	set threshold to 3.5; # 3.5 standard deviations for signal
	set influence to 0.5; # between 0 and 1, where 1 is normal influence, 0.5 is half
	*/

	// ZScore on 16bit WAV samples
	func ZScore(samples []int16, lag int, threshold float64, influence float64) (signals []int16) {
	//lag := 20