Carlo van Wyk thecarlo

WebSockets - An Introduction

WebSockets is a modern HTML5 standard which makes communication between client and server a lot more simpler than ever. We are all familiar with the technology of sockets. Sockets have been fundamental to network communication for a long time but usually the communication over the browser has been restricted. The general restrictions

The server used to have a permanent listener while the client (aka browser) was not designated any fixed listener for a more long term connection. Hence, every communication was restricted to the client demanding and the server responding.
This meant that unless the client requested for a particular resource, the server was unable to push such a resource to the client.
This was detrimental since the client is then forced to check with the server at regular intervals. This meant a lot of libraries focused on optimizing asynchronous calls and identifying the response of asynchronous calls. Notably t

Git

Learning Resources

Git from the Bottom Up
Using Git (GitLab Docs)
Using Git Effectively
A beginner's guide to Git version control (HN)

Add Git Branch Name to Terminal Prompt (Linux/Mac)

Open ~/.bash_profile in your favorite editor and add the following content to the bottom.

# Git branch in prompt.

parse_git_branch() {

	var request = require('request');
	var unzip = require('unzip');
	var csv2 = require('csv2');

	request.get('http://s3.amazonaws.com/alexa-static/top-1m.csv.zip')
	.pipe(unzip.Parse())
	.on('entry', function (entry) {
	entry.pipe(csv2()).on('data', console.log);
	})
	;

	/*
	This brute force algorithm was originally written (by me) back in 1998, and has been collecting dust
	since then. However, for the purpose of testing Gist on GitHub I decided to rewrite the algorithm
	from VB6 to C#, make some improvements and release this fast, compact, non-recursive, brute force
	algorithm under the MIT license: http://opensource.org/licenses/MIT

	Notes:
	- Do a run with testLetters = "0123456789" and testLength = 3, to see what happens
	- Remember to keep the callback testCalback as fast as possible
	- Tweet some love to @fredrikdev :)

	#
	# Name: nginx-tls.conf
	# Auth: Gavin Lloyd <[email protected]>
	# Desc: Nginx SSL/TLS configuration for "A+" Qualys SSL Labs rating
	#
	# Enables HTTP/2, PFS, HSTS and OCSP stapling. Configuration options not related
	# to SSL/TLS are not included here.
	#
	# Additional tips:
	#

	# Ask for the user password
	# Script only works if sudo caches the password for a few minutes
	sudo true

	# Install kernel extra's to enable docker aufs support
	# sudo apt-get -y install linux-image-extra-$(uname -r)

	# Add Docker PPA and install latest version
	# sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys 36A1D7869245C8950F966E92D8576A8BA88D21E9
	# sudo sh -c "echo deb https://get.docker.io/ubuntu docker main > /etc/apt/sources.list.d/docker.list"

	###############################################################################
	# Helpful Docker commands and code snippets
	###############################################################################

	### CONTAINERS ###
	docker stop $(docker ps -a -q) #stop ALL containers
	docker rm -f $(docker ps -a -q) # remove ALL containers
	docker rm -f $(sudo docker ps --before="container_id_here" -q) # can also filter

	# exec into container

	var amqp = require('amqplib/callback_api');

	// if the connection is closed or fails to be established at all, we will reconnect
	var amqpConn = null;
	function start() {
	amqp.connect(process.env.CLOUDAMQP_URL + "?heartbeat=60", function(err, conn) {
	if (err) {
	console.error("[AMQP]", err.message);
	return setTimeout(start, 1000);
	}