Julik Tarkhanov julik

💭

🎺

It's just the beginning

julik / database_context.rb

Created April 22, 2025 09:37

	# This class encapsulates a unit of work done for a particular tenant, connected to that tenant's database.
	# ActiveRecord makes it _very_ hard to do in a simple manner and clever stuff is required, but it is knowable.
	#
	# What this class provides is a "misuse" of the database "roles" of ActiveRecord to have a role per tenant.
	# If all the tenants are predefined, it can be done roughly so:
	#
	# ActiveRecord::Base.legacy_connection_handling = false if ActiveRecord::Base.respond_to?(:legacy_connection_handling)
	# $databases.each_pair do \|n, db_path\|
	# config_hash = {
	# "adapter" => 'sqlite3',

julik / styled_templates.rb

Last active April 22, 2025 09:29

styled_templates.rb

	# <%= style_for_this_template do %>
	# width: 128px;
	# .caption {
	# font-size: 12px;
	# text-align: center;
	# }
	# <% end %>
	# <div class="<%= css_class_for_this_template %>">
	# <div class="title">Hello!</div>
	# </div>

julik / sqlite-multi-test.rb

Created April 21, 2025 12:19

	require 'bundler/inline'
	require "logger"

	gemfile do
	source 'https://rubygems.org'
	gem "activerecord", "~> 6", require: "active_record"
	gem "sqlite3", "~> 1.1" # This has to be of a version activerecord supports, so can't be 2.x
	end

	16.times do \|n\|

julik / musherator.rb

Created March 11, 2025 12:39

julik / replicate.html

Created February 22, 2025 19:50

	<!DOCTYPE html>
	<html>
	<head>
	<style>
	.outlinerounded {
	width: 1px; height: 1px; overflow: hidden; border: 1px solid gray;
	}
	</style>
	</head>
	<body>

julik / rae.rb

Created February 13, 2025 01:04

AES encryption with random access to plaintext (playground)

	require "openssl"
	require "stringio"

	class PassthruScheme
	READ_OR_WRITE_CHUNK_SIZE = 1 << 16

	def streaming_encrypt(from_plaintext_io, into_ciphertext_io)
	while (chunk = from_plaintext_io.read(READ_OR_WRITE_CHUNK_SIZE))
	into_ciphertext_io.write(chunk)
	end

julik / substreams.rb

Created February 7, 2025 16:32

AES-CFB with substream-based blocks

	# frozen_string_literal: true

	require "test_helper"

	class BlockwiseEncryptionTest < ActiveSupport::TestCase
	class NonRandomAccessible
	def initialize(encryption_key)
	@algo = "aes-256-cfb"
	@iv_and_key_length = 16 + 32
	@key_derivation_salt = "my desire"

julik / deploy.sh

Created April 30, 2024 08:31

	#!/usr/bin/env bash

	set -e

	# This script will build a Docker image from the current state of the working tree.
	# It will tag it with the short Git sha, and then push it to Quay.io under our company
	# account. Afterwards the image can be picked up from other hosts to deploy.

	export DEPLOY_HOST=<someapp>.<my-domain>
	export REV=`git log -1 --pretty=%h`

julik / streaming_controller.rb

Created February 24, 2024 01:47

	class StreamingController < ApplicationController
	class Writer
	def initialize(&blk)
	@blk = blk
	end

	def write(stuff)
	@blk.call(stuff)
	stuff.bytesize
	end

julik / pecobox.rb

Created February 9, 2024 14:59

A circuit breaker using Pecorino leaky buckets

	# frozen_string_literal: true

	# Pecobox is a Circuitbox-like class which uses Pecorino for
	# measurement error rates. It is less resilient than Circuitbox
	# because your error stats are stored in the database, but guess what:
	# if your database is down your product is already down, so there is
	# nothing to circuit-protect. And having a shared data store for
	# the circuits allows us to track across machines and processes, so
	# we do not have to have every worker hammer at an already failing
	# resource right after start