Alexey Kopytko sanmai

using Ansible command line:

ansible-playbook --connection=local 127.0.0.1 playbook.yml

using inventory:

127.0.0.1 ansible_connection=local

Получаем бесплатный SSL сертификат для этого домена:

Настраиваем этот домен в nginx с указанием HSTS заголовка:

add_header Strict-Transport-Security "max-age=10886400; includeSubDomains; preload";

Добавляем его в HSTS preload list.

Waveguide theory

http://www.antenna-theory.com/tutorial/waveguides/waveguide.php

Cutoff frequency

Circular waveguide cutoff frequency equation for TE11 mode

fc = 1.8412 c / 2 pi a = 1.8412 c / pi D

Better SSH Authorized Keys Management

A seemingly common problem that people encounter is how to handle all of your users authorized_keys file.

People struggle over management, ensuring that users only have specific keys in the authorized_keys file or even a method for expiring keys. A centralized key management system could help provide all of this functionality with a little scripting.

One piece of functionality overlooked in OpenSSH is the AuthorizedKeysCommand configuration keyword. This configuration allows you to specify a command that will run during login to retrieve a users public key file from a remote source and perform validation just as if the authorized_keys file was local.

Here is an example directory structure for a set of users with SSH public keys that can be shared out via a web server:

The introduction to Reactive Programming you've been missing

(by @andrestaltz)

This tutorial as a series of videos

If you prefer to watch video tutorials with live-coding, then check out this series I recorded with the same contents as in this article: Egghead.io - Introduction to Reactive Programming.

	#Resource reference: https://docs.omniref.com/github/veracross/active_merchant/HEAD/symbols/ActiveMerchant::Billing::GmoGateway#line=46
	# The API does not return error messages, so I translated these from the
	# example english-like messages in the GMO documentation
	ERROR_CODES = {
	'E01010001' => 'Shop ID not specified',
	'E01010008' => 'Shop ID contains invalid characters or is too long',
	'E01010010' => 'Shop ID is invalid',
	'E01020001' => 'Shop Password not specified',
	'E01020008' => 'Shop Password contains invalid characters or is too long',
	'E01030002' => 'Shop ID and Password are invalid',

	# In order for gpg to find gpg-agent, gpg-agent must be running, and there must be an env
	# variable pointing GPG to the gpg-agent socket. This little script, which must be sourced
	# in your shell's init script (ie, .bash_profile, .zshrc, whatever), will either start
	# gpg-agent or set up the GPG_AGENT_INFO variable if it's already running.

	# Add the following to your shell init to set up gpg-agent automatically for every shell
	if [ -f ~/.gnupg/.gpg-agent-info ] && [ -n "$(pgrep gpg-agent)" ]; then
	source ~/.gnupg/.gpg-agent-info
	export GPG_AGENT_INFO
	else


	In .gitattributes (alongside .gitignore in top repo dir) add:
	*.mo diff=mo2po

	In .git/config add (msgunfmt converts an mo to a po file):
	[diff "mo2po"]
	textconv = msgunfmt

	More info at https://git-scm.com/book/en/v2/Customizing-Git-Git-Attributes#Binary-Files

	# OSX for Hackers (Mavericks/Yosemite)
	#
	# Source: https://gist.github.com/brandonb927/3195465

	#!/bin/sh

	# Some things taken from here
	# https://github.com/mathiasbynens/dotfiles/blob/master/.osx

	# Ask for the administrator password upfront

	# For each database:
	ALTER DATABASE database_name CHARACTER SET = utf8mb4 COLLATE = utf8mb4_unicode_ci;
	# For each table:
	ALTER TABLE table_name CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;
	# For each column:
	ALTER TABLE table_name CHANGE column_name column_name VARCHAR(191) CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;
	# (Don’t blindly copy-paste this! The exact statement depends on the column type, maximum length, and other properties. The above line is just an example for a `VARCHAR` column.)