Jose C Fernandez Joseworks

When should you use DateTime and when should you use Time?

It's a common misconception that [William Shakespeare][1] and [Miguel de Cervantes][2] died on the same day in history - so much so that UNESCO named April 23 as [World Book Day because of this fact][3]. However because England hadn't yet adopted [Gregorian Calendar Reform][4] (and wouldn't until [1752][5]) their deaths are actually 10 days apart. Since Ruby's Time class implements a [proleptic Gregorian calendar][6] and has no concept of calendar reform then there's no way to express this. This is where DateTime steps in:

>> shakespeare = DateTime.iso8601('1616-04-23', Date::ENGLAND)
=> Tue, 23 Apr 1616 00:00:00 +0000
>> cervantes = DateTime.iso8601('1616-04-23', Date::ITALY)
=> Sat, 23 Apr 1616 00:00:00 +0000

Building custom ruby-alpine

Check the alpine version of the previous image.

alpine3.9 master$ docker run -it ruby:2.5.4-alpine sh
/ # cat /etc/alpine-release 
3.9.2
/ # ruby -v
ruby 2.5.4p155 (2019-03-13 revision 67245) [x86_64-linux-musl]

Sending emails with ActionMailer and Sidekiq

Send email asynchroniously using Sidekiq.

ActionMailer

Create your mailer us usual:

	# place this in lib/fakeout.rb

	require 'ffaker'

	module Fakeout
	class Builder

	FAKEABLE = %w(User Product)

	attr_accessor :report

	class MoveAttachmentsToNewLocation < ActiveRecord::Migration
	def initialize(name = self.class.name, version = nil)
	access_key = Rails.application.secrets.g3_access_key_id
	secret_key = Rails.application.secrets.g3_secret_access_key
	storage = Fog::Storage::Google.new google_storage_access_key_id: access_key,
	google_storage_secret_access_key: secret_key

	@bucket_name = Rails.application.secrets.g3_bucket
	@bucket = storage.directories.get(@bucket_name)
	super(name, version)

	# Ruby Array's "-" (minus) method removes elements from the receiver which exist in the parameter Array

	[5, 6, 1] - [2, 3, 5]

	# => [6, 1]

	# this #subtract method will subtract the value of the parameter Array from the value of the receiver Array, defined by the actual index.
	# type mismatch, Nil, and different Array length are not handled

	class Array

	class Child extends React.Component {
	render () {
	return (<div>I'm the child</div>);
	}
	}

	class ShowHide extends React.Component {
	constructor () {
	super ();
	this.state = {

	# app/models/user.rb
	class User < ActiveRecord::Base
	validates :zip_code, presence: true, zip_code: true
	end

	%w(john paul ringo george).map { \|p\| p.capitalize }
	# => ["John", "Paul", "Ringo", "George"]