aCandidMind

SOLID Principles with ruby examples

SRP - Single responsibility principle

A class should have only a single responsibility.

Every class should have a single responsibility, and that responsibility should be entirely encapsulated. All its services should be narrowly aligned with that responsibility, this embrace the high cohesion.

OCP - Open/closed principle

Software entities should be open for extension, but closed for modification.

#Start a machine use any method you like here, I'm doing it from the command line 40 cores, 120GB RAM, SSD with 8,500 IOPS (SAN) - Amazon linux (Centos)

ec2-run-instances ami-a10897d6 -t m4.10xlarge -g jlp -k john_page_demos -b "/dev/xvdb=:725:true:io1:8500"

#Log on

ssh -L 27017:localhost:27017 -i <your public key>.pem ec2-user@<your ip address>

#Set up disk

DB OpenData

DB OpenData Portal:

http://data.deutschebahn.com/

DB OpenData on GitHub:

https://github.com/dbopendata/

Server Price Breakdown: DigitalOcean, Amazon AWS LightSail, Vultr, Linode, OVH, Hetzner, Scaleway/Online.net:

Permalink: git.io/vps

$5/mo

Provider	Type	RAM	Cores	Storage	Transfer	Network	Price

Use nginx as Non-Transparent SSL Proxy

Introduction

Many mobile apps have back-end API servers. They usually rely on the API replies to determine whether certain information is supposed to be shown. If the API responses could be manipulated on the fly, we may easily fool an unmodified app to expose some private data.

This manual guides you to set up nginx as non-transparent SSL proxy, which just subsitutes strings in the server responses (i.e. man-in-the-middle attack ourself). For both server-side (their API servers) and client-side (your device), the whole process is almost transparent.

	#!/usr/bin/env ruby

	# Only tags >= min_tag will be removed.
	min_tag = '0.0.0'
	tags = `git tag`.split(/\s+/).select do \|t\|
	Gem::Version.new(t) >= Gem::Version.new(min_tag)
	end

	`git tag -d #{tags.join ' '}`
	`git push origin #{tags.map { \|t\| ':' + t }.join ' '}`

	import {Observable} from 'rx';
	import {DOM} from 'rx-dom';

	import {toArray, getNodesFromSelector} from './utils';

	let interactions_ = {
	'click': Observable.fromEvent(document.body, 'click')
	}

	let mutations_ = DOM

	#!/usr/bin/env bash

	# Script to (selectively) save/load multiple Docker images to/from a directory.
	# Run ./save-load-docker-images.sh for help.

	set -e

	directory=$PWD
	filter=""
	compress=0

	require 'webrick'
	require 'fileutils'

	BIND_ADDRESS = "127.0.0.1"
	PORT = 8080

	BACKUP_DIR = 'bak'

	if ARGV.length != 0
	root = ARGV.first.gsub('\\', '/')

	#!/bin/bash
	/usr/sbin/usermod -aG docker <user>