Jason Chalom TRex22

tmux shortcuts & cheatsheet

start new:

tmux

start new with session name:

tmux new -s myname

Firing up LaTex on macOS 🔥

As I'm writing this small tutorial, I assume you've read my previous one about setting up macOS, so if for any tool I'll use without explanation, look to that other article.

MacTex

The full version IS NOT MANDATORY, as in the tutorial that follows I installed the smaller version of MacTeX and proceded installing every needed dependency. Installing the complete package is about ~3.5GB of download and ~5GB on disk, the smaller one is just about 80MBs.

Click here to download the complete version or here to download the smaller version.

Gnuplot

Arch Linux ARM 64 on Raspberry Pi 3 B+ With Full Disk Encryption And SSH Unlock: 2018 Edition

There are multiple ways to get a full disk encrypted arch linux system on raspberry. In this tutorial, we will install a 64-bit arch linux armv8 system, using dropbear as ssh server for remote pre-boot unlocking of the root filesystem. However, it will still be possible to unlock and use the pi as usual, with a keyboard and monitor. We will also create an unencrypted partition in the installation process, usable as a rescue system.

Differences to the 32-bit arch linux arm version:

probably better performance
can run 64-bit software
comes without the proprietary video-driver blobs

https://gist.github.com/zhengjia/428105

https://devhints.io/capybara

https://robwise.github.io/blog/testing-react-select-with-capybara.html

JedWatson/react-select#832

https://www.ombulabs.com/blog/rails/react/how-to-test-a-react-app-using-capybara-webkit.html

Kill a process by ip connection

kill -9 $(lsof -i tcp:80 -t)

Reset OpenSSH-Server config (debian dpkg based)

sudo rm /etc/ssh/ssh_host_*
sudo dpkg-reconfigure openssh-server

	module StringParser
	extend self

	def numeric?(str)
	!!(str =~ /\A[+-]?\d+(\.[\d]+)?\z/)
	end

	def integer?(str)
	!!(str =~ /\A[+-]?\d+\z/)
	end

	TIME_CHUNK_INTERVAL = 10.hours

	# [[start,end], [start,end]...]
	def fetch_time_chunks(start_time, end_time, time_interval = nil)
	interval = time_interval \|\| TIME_CHUNK_INTERVAL

	time_delta = end_time - start_time
	number_of_chunks = (time_delta / interval).to_i

	return [[start_time, end_time]] if number_of_chunks == 0

	module StringSanitizer
	extend self

	##
	# This is used for different kinds of cleanup of a string
	# Use cases:
	# 1. When creating reports in different formats with varying support for unicode.
	# 2. For Data inputs to remove whitespace and strange characters which are not "language"
	# 3. External services which may not be able to handle different character sets
	# 4. Comparisons - when comapring two strings which have whitespace and weird unicode

	module ArrayKeyValueCleaner
	extend self

	# This makes use of a recursive proc to recurse into a deeply
	# nested set of arrays
	#
	# At the deepest array it will check if the next set of children
	# are not arrays and make sure they are valid key value pairs
	def call(value)
	return value unless value.is_a?(Array)