abhilashak

Deploy Rails Application to AWS EC2

Creating AWS EC2 Instance

- login to 'AWS Management Console' (https://aws.amazon.com/console/)
- from 'Services'(in navbar) choose 'EC2'
- from 'Create Instance' section, click on 'Launch Instance'
- then select 'AMI' (Amazon Machine Image), we will be using 'Ubuntu Server 16.04 LTS (HVM)' as example
- select 'Instance Type' as per your requirement
- then click 'Next:Configure Instance Details' to continue
  change 'Configure Instance Details' or used as default settings

abhilashak

require 'English'

namespace :db do # rubocop:disable Metrics/BlockLength
  task :prevent_disparate_pg_dump_versions => :environment do
    allowed_pg_dump_version = '9.6.10'.freeze

    `pg_dump --version`
    pg_dump_exit_status = $CHILD_STATUS.exitstatus

    locally_installed_version = `pg_dump --version`.chomp[/(\d.*)/,1] rescue nil

abhilashak

'use strict';

const crypto = require('crypto');

const ENCRYPTION_KEY = process.env.ENCRYPTION_KEY; // Must be 256 bits (32 characters)
const IV_LENGTH = 16; // For AES, this is always 16

function encrypt(text) {
 let iv = crypto.randomBytes(IV_LENGTH);
 let cipher = crypto.createCipheriv('aes-256-cbc', Buffer.from(ENCRYPTION_KEY), iv);

abhilashak

# deb cdrom:[Ubuntu 19.10 _Eoan Ermine_ - Release amd64 (20191017)]/ eoan main restricted

# See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to
# newer versions of the distribution.
deb http://id.archive.ubuntu.com/ubuntu/ eoan main restricted
# deb-src http://id.archive.ubuntu.com/ubuntu/ eoan main restricted

## Major bug fix updates produced after the final release of the
## distribution.
deb http://id.archive.ubuntu.com/ubuntu/ eoan-updates main restricted

abhilashak

#deb cdrom:[Ubuntu 18.04 LTS _Bionic Beaver_ - Release amd64 (20180426)]/ bionic main restricted

# See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to
# newer versions of the distribution.
deb http://us.archive.ubuntu.com/ubuntu/ bionic main restricted
# deb-src http://us.archive.ubuntu.com/ubuntu/ bionic main restricted

## Major bug fix updates produced after the final release of the
## distribution.
deb http://us.archive.ubuntu.com/ubuntu/ bionic-updates main restricted

abhilashak

If your master.key has been compromised, you might want to regenerate it.

No key regeneration feature at the moment. We have to do it manually.

1. Copy content of original credentials rails credentials:show somewhere temporarily.
2. Remove config/master.key and config/credentials.yml.enc
3. Run EDITOR=vim rails credentials:edit in the terminal: This command will create a new master.key and credentials.yml.enc if they do not exist.
4. Paste the original credentials you copied (step 1) in the new credentials file (and save + quit vim)
5. Add and Commit the file config/credentials.yml.enc

abhilashak

Run rails new --help to view all of the options you can use to generate new Rails application:

Output for Rails 6+

Usage:
  rails new APP_PATH [options]

Options:
      [--skip-namespace], [--no-skip-namespace]              # Skip namespace (affects only isolated applications)

abhilashak

require 'benchmark'

count = 1000000
Benchmark.benchmark do |bm|
	bm.report("concat") { count.times { 11.to_s + '/' + 12.to_s } }
	bm.report("interp") { count.times { "#{11}/#{12}" } }
end

abhilashak

require 'sinatra'

get '/long_process' do
  
  child_pid = Process.fork do
    # hard work is done here...
    sleep 10
    Process.exit
  end
  

abhilashak

; Berengar W. Lehr ([email protected])
; Medical Physics Group, Department of Diagnostic and Interventional Radiology
; Jena University Hospital, 07743 Jena, Thueringen, Germany
;
; This program is free software; you can redistribute it and/or modify
; it under the terms of the GNU General Public License as published by
; the Free Software Foundation; either version 2 of the License, or
; (at your option) any later version.
;
; This program is distributed in the hope that it will be useful,