Thanh Huynh hkthanh89

Self Signed SSL Certificate for AWS ALB

Generate private key

$> openssl genrsa 2048 > my-private-key.pem

Generate certificate using private key, you will be prompted to fill some fields. Fill required fields randomly, except for Common Name fill it with *.amazonaws.com or your valid domain name

Interview Questions

Node.js

Q1: What do you mean by Asynchronous API? ☆☆

Answer: All APIs of Node.js library are aynchronous that is non-blocking. It essentially means a Node.js based server never waits for a API to return data. Server moves to next API after calling it and a notification mechanism of Events of Node.js helps server to get response from the previous API call.

Source: tutorialspoint.com

FWIW: I didn't produce the content presented here (the outline from Edmond Lau's book). I've just copy-pasted it from somewhere over the Internet, but I cannot remember what exactly the original source is. I was also not able to find the author's name, so I cannot give him/her the proper credits.

Effective Engineer - Notes

By Edmond Lau
Highly Recommended 👍
http://www.theeffectiveengineer.com/

What's an Effective Engineer?

This guide assumes that you recently run brew upgrade postgresql and discovered to your dismay that you accidentally bumped from one major version to another: say 9.3.x to 9.4.x. Yes, that is a major version bump in PG land.

First let's check something.

brew info postgresql

The top of what gets printed as a result is the most important:

DigitalOcean Ubuntu 14.04 x64 + Rails 4 + Nginx + Unicorn + PostgreSQL + Capistrano 3

Create a Droplet

SSH into Root

$ ssh root@123.123.123.123

Change Root Password

	# encoding: utf-8

	##
	# Backup Generated: my_database_backup
	# Once configured, you can run the backup with the following command:
	#
	# $ backup perform -t my_database_backup [-c <path_to_configuration_file>]
	#
	# For more information about Backup's components, see the documentation at:
	# http://backup.github.io/backup

	Structure data:
	- iOS:
	{
	alert: "Message show in notification",
	badge: 1,
	sound: "siren.aiff",
	expiry: Time.now + 60*60,
	content_available: true,
	custom: {
	event_type: "doctor_on_way",

	# encoding: utf-8

	##
	# Backup Generated: my_database_backup
	# Once configured, you can run the backup with the following command:
	#
	# $ backup perform -t my_database_backup [-c <path_to_configuration_file>]
	#
	# For more information about Backup's components, see the documentation at:
	# http://backup.github.io/backup

	class Banner < ActiveRecord::Base
	attr_accessor :image_width, :image_height
	mount_uploader :image, ImageUploader

	validate :check_dimensions, :on => :create
	def check_dimensions
	if !image_cache.nil? && (image.width < 300 \|\| image.height < 300)
	errors.add :image, "Dimension too small."
	end
	end

	:80 {
	root /serve
	}