Martin Peters FreakyBytes

Code is clean if it can be understood easily – by everyone on the team. Clean code can be read and enhanced by a developer other than its original author. With understandability comes readability, changeability, extensibility and maintainability.

General rules

Follow standard conventions.
Keep it simple stupid. Simpler is always better. Reduce complexity as much as possible.
Boy scout rule. Leave the campground cleaner than you found it.
Always find root cause. Always look for the root cause of a problem.

Design rules

1944 Simple Sabotage Field Manual, by Strategic Services

https://www.cia.gov/news-information/featured-story-archive/2012-featured-story-archive/CleanedUOSSSimpleSabotage_sm.pdf

Title: Simple Sabotage Field Manual Author: Strategic Services Office of Strategic Services

	blueprint:
	name: Low battery level detection & notification for all battery sensors
	description: Regularly test all sensors with 'battery' device-class for crossing
	a certain battery level threshold and if so execute an action.
	domain: automation
	input:
	threshold:
	name: Battery warning level threshold
	description: Battery sensors below threshold are assumed to be low-battery (as
	well as binary battery sensors with value 'on').

	const sessionId = Cypress.env('sessionId');
	const appFrame = window.parent.document.querySelectorAll('iframe')[0];

	Cypress.on('window:load', () => {
	appFrame.contentWindow.eval(`
	const request = new XMLHttpRequest();
	request.open('GET', 'https://cdn.jsdelivr.net/npm/[email protected]/dist/rrweb.min.js', false);
	request.send('');
	const script = document.createElement('script');
	script.type = 'text/javascript';

	# Haproxy configuration for SSL request passthrough to different backend based on SNI read from Handshaking stage
	# The Loadbalance will not decode the encrpted data but transparently transfer to the backend server in Private subnet.
	# With such configuration, you can install multiply services with its own SSL certificate in backend in different EC2 instance, but only explosure to public internet with one Loadbalance IP. There is no need to install SSL certificate in Loadbalancer level.

	# Ref:
	# How to support wildcard sni: https://stackoverflow.com/questions/24839318/haproxy-reverse-proxy-sni-wildcard
	# https://www.haproxy.com/blog/enhanced-ssl-load-balancing-with-server-name-indication-sni-tls-extension/
	# https://stuff-things.net/2016/11/30/haproxy-sni/

	#!/usr/bin/env python
	import argparse
	import base64
	import json
	import os


	def main():
	parser = argparse.ArgumentParser(
	description="Dump all certificates out of Traefik's acme.json file")

	#!/usr/bin/env python
	import argparse
	import base64
	import json
	import os
	import shlex
	import subprocess
	import sys


	get_latest_release() {
	curl --silent "https://api.github.com/repos/$1/releases/latest" \| # Get latest release from GitHub api
	grep '"tag_name":' \| # Get tag line
	sed -E 's/."([^"]+)"./\1/' # Pluck JSON value
	}

	# Usage
	# $ get_latest_release "creationix/nvm"
	# v0.31.4

	- What do Etcd, Consul, and Zookeeper do?
	- Service Registration:
	- Host, port number, and sometimes authentication credentials, protocols, versions
	numbers, and/or environment details.
	- Service Discovery:
	- Ability for client application to query the central registry to learn of service location.
	- Consistent and durable general-purpose K/V store across distributed system.
	- Some solutions support this better than others.
	- Based on Paxos or some derivative (i.e. Raft) algorithm to quickly converge to a consistent state.
	- Centralized locking can be based on this K/V store.