Deploying Rails Action Cable to Linux

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Selected VPS: Linode, 1GB Ram, 20 GB SSD, 1 TB transfer
OS: Ubuntu 18.04 LTS
App server: Passenger
Web Server: Ngnix

If you’d like to try Linode, I would greatly appreciate using this referral link – Linode: SSD Cloud Hosting & Linux Servers

Guide

First step – boot your server from Linode Manager Dashboard and ssh into it

General Server Updates

apt-get update && apt-get upgrade

#If desired to run auto-updates
apt-get install unattended-upgrades
dpkg-reconfigure --priority=low unattended-upgrades

Set timezone:

dpkg-reconfigure tzdata
sudo service rsyslog restart

Security:

fail2ban

sudo apt-get install fail2ban

awk '{ printf "# "; print; }' /etc/fail2ban/jail.conf | sudo tee /etc/fail2ban/jail.local
vim /etc/fail2ban/jail.conf

uncomment sshd section and add
enabled = true

sudo apt-get install sendmail iptables-persistent
sudo service fail2ban start

Firewall ( allow established connections, traffic generated by the server itself, traffic destined for our SSH and web server ports. We will drop all other traffic):

sudo service fail2ban stop
sudo iptables -A INPUT -i lo -j ACCEPT
sudo iptables -A INPUT -m conntrack --ctstate ESTABLISHED,RELATED -j ACCEPT
sudo iptables -A INPUT -p tcp --dport 22 -j ACCEPT
sudo iptables -A INPUT -p tcp -m multiport --dports 80,443 -j ACCEPT
sudo iptables -A INPUT -j DROP

#easy way to rate-limit ssh with ufw:
# technically, we could do all of the iptables stuff with ufw
ufw enable
ufw limit ssh

If using IPv6:

ip6tables -A INPUT -p tcp --dport 80 -j ACCEPT
ip6tables -A INPUT -p tcp --dport 443 -j ACCEPT
ip6tables -A INPUT -p tcp --dport 22 -j ACCEPT # (replace with your undisclosed port)
ip6tables -A INPUT -p icmpv6 -j ACCEPT
ip6tables -A INPUT -j REJECT
ip6tables -A FORWARD -j REJECT

View iptables rules:

sudo iptables -S

Save iptables rules:

sudo dpkg-reconfigure iptables-persistent
sudo service fail2ban start

Create a deploy user

sudo adduser deploy
sudo adduser deploy sudo
su deploy

Installing Ruby (2.4)

Prereq’s:

sudo apt-get install git-core curl zlib1g-dev build-essential libssl-dev libreadline-dev libyaml-dev libsqlite3-dev sqlite3 libxml2-dev libxslt1-dev libcurl4-openssl-dev python-software-properties libffi-dev nodejs

cd
git clone https://github.com/rbenv/rbenv.git ~/.rbenv
echo 'export PATH="$HOME/.rbenv/bin:$PATH"' >> ~/.bashrc
echo 'eval "$(rbenv init -)"' >> ~/.bashrc
exec $SHELL

git clone https://github.com/rbenv/ruby-build.git ~/.rbenv/plugins/ruby-build
echo 'export PATH="$HOME/.rbenv/plugins/ruby-build/bin:$PATH"' >> ~/.bashrc
exec $SHELL

rbenv install 2.4.0
rbenv global 2.4.0
ruby -v

gem install bundler

Nginx

sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys 561F9B9CAC40B2F7
sudo apt-get install -y apt-transport-https ca-certificates

# Add Passenger APT repository
sudo sh -c 'echo deb https://oss-binaries.phusionpassenger.com/apt/passenger xenial main > /etc/apt/sources.list.d/passenger.list'
sudo apt-get update

# Install Passenger & Nginx
sudo apt-get install -y nginx-extras passenger

Nginx update for Ubuntu 17.10 zesty

sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys 561F9B9CAC40B2F7
sudo apt-get install -y apt-transport-https ca-certificates

# Add our APT repository
sudo sh -c 'echo deb https://oss-binaries.phusionpassenger.com/apt/passenger zesty main > /etc/apt/sources.list.d/passenger.list'
sudo apt-get update
# Install Passenger + Nginx module
sudo apt-get install -y libnginx-mod-http-passenger libnginx-mod-http-headers-more-filter nginx

Nginx update for Ubuntu 18.04 bionic

sudo sh -c 'echo deb https://oss-binaries.phusionpassenger.com/apt/passenger bionic main > /etc/apt/sources.list.d/passenger.list'

sudo apt-get update
sudo apt-get install -y libnginx-mod-http-passenger

Block anything you don’t want in Nginx

vim /etc/nginx/sites-enabled/default
location ~ ^/(wp-admin|wp-content|wp-login) {
 deny all;
}

Set Cache headers

location ^~ /assets/ {
        gzip_static on;
        expires 1d;
        add_header Cache-Control "public";
}

location ~* \.(?:jpg|jpeg|gif|png|ico|cur|gz|svg|svgz|mp4|ogg|ogv|webm|htc)$ {
  expires 30d;
  access_log off;
  add_header Cache-Control "public";
}

Prevent access by IP

vim /etc/nginx/sites-enabled/default
server {
        listen 80;
        listen 443;
        server_name _put_server_ip_here;
        return 404;
}



Start Nginx:
sudo service nginx start


Nginx config:
sudo vim /etc/nginx/nginx.conf
Uncomment Phusion config – include /etc/nginx/passenger.conf;



Update passenger config:
sudo vim /etc/nginx/passenger.conf

passenger_ruby /home/deploy/.rbenv/shims/ruby;
passenger_root /usr/lib/ruby/vendor_ruby/phusion_passenger/locations.ini;
#passenger_ruby /usr/bin/passenger_free_ruby;



Restart Nginx
sudo service nginx restart

Test Nginx Config with gixy

We will need python-pip in order to install gixy:

apt-get install python-pip
pip install --upgrade pip
pip -V

pip install gixy

gixy

Postgres

sudo apt-get install postgresql postgresql-contrib libpq-dev

Postgres update for Ubuntu 17.10

sudo apt-get install postgresql-9.6
sudo apt-get install python-psycopg2
sudo apt-get install libpq-dev

Postgres update for Ubuntu 18.04

touch /etc/apt/sources.list.d/pgdg.list
sudo sh -c 'echo deb http://apt.postgresql.org/pub/repos/apt/ bionic-pgdg main > /etc/apt/sources.list.d/pgdg.list'

wget --quiet -O - https://www.postgresql.org/media/keys/ACCC4CF8.asc | sudo apt-key add -
sudo apt-get update

apt-get install postgresql-10

#Migrate Postresql from 9.6 to 10
sudo pg_dropcluster 10 main --stop
sudo systemctl stop postgresql 
sudo pg_upgradecluster  9.6 main
sudo pg_dropcluster 9.6 main --stop

Ensure UTF-8 support before creating a new database
vim /etc/profile.d/lang.sh
Add the following if not already there:

export LANGUAGE="en_US.UTF-8"
export LANG="en_US.UTF-8"
export LC_ALL="en_US.UTF-8"

Create a Database with a user (Make sure to change the app name):

sudo su - postgres
createuser --pwprompt deploy
sudo su - deploy
psql
create database your_db_name_production_new with owner=deploy encoding='UTF-8';

exit

Creating dumps

pg_dump db_name_production -U deploy -h localhost > db_name_production_backup
# To restore:
psql -d db_name_production -f db_name_production_backup

#if you want to scp it from somewhere else(assuming dumps are in ~/dumps):
scp -r [email protected]_ip:~/dumps ~/destination_dumps

Capistrano

On your local machine add to your Gemfile:

gem 'capistrano', '~> 3.7', '>= 3.7.1'
gem 'capistrano-passenger', '~> 0.2.0'
gem 'capistrano-rails', '~> 1.2'

group :production do
  gem 'capistrano-rbenv', '~> 2.1'
end

Generate configs:

cap install STAGES=production

Update Capfile:

# If you are using rbenv add these lines:
# require 'capistrano/rbenv'
# set :rbenv_type, :user
# set :rbenv_ruby, '2.4.0'

Update deploy.rb:

set :application, "my_app_name"
set :repo_url, "[email protected]:me/my_repo.git"

set :deploy_to, '/home/deploy/my_app_name'

append :linked_files, "config/database.yml", "config/secrets.yml"
append :linked_dirs, "log", "tmp/pids", "tmp/cache", "tmp/sockets", "vendor/bundle", "public/system", "public/uploads"

Update production.rb with the server IP:
server ‘127.0.0.1’, user: ‘deploy’, roles: %w{app db web}

Had to manually create database.yml and secrets.yml for now in /home/deploy/my_app_name/shared/config and copy connection data. This should be automated later

Update /etc/nginx/sites-enabled/default

server {
        listen 80;
        listen [::]:80 ipv6only=on;

        server_name mydomain.com;
        passenger_enabled on;
        rails_env    production;
        root         /home/deploy/my_app_name/current/public;
        
#action cable config:
        location /cable {
                 passenger_app_group_name app_name_websocket;
                 passenger_force_max_concurrent_requests_per_process 0;
        }
}

Redis

sudo apt-get install redis-server

sudo service nginx restart

Time Synchronization

sudo apt-get update
sudo apt-get install ntp

systemctl start ntp.service
sudo ntpq -p

Let’s Encrypt (optional step)

Install certbot

apt-get install software-properties-common
add-apt-repository ppa:certbot/certbot
apt-get update
apt-get install certbot

Add to /etc/nginx/sites-available/default (this may be necessary for the Webroot plugin, which we’ll use to generate the certs)

location ^~ /.well-known/acme-challenge {
  root /var/www/html;
  default_type "text/plain";
  try_files $uri =404;
}

Verify config and restart:

nginx -t		
systemctl restart nginx

Get your webroot path from /etc/nginx/sites-available/default

Generate certs(replace domain an dweb-root-path):

certbot certonly --webroot --webroot-path=/var/www/html -d example.com -d www.example.com

Add a snippet:
vim /etc/nginx/snippets/ssl-example.com.conf
Paste the following:

ssl_certificate /etc/letsencrypt/live/example.com/fullchain.pem;
ssl_certificate_key /etc/letsencrypt/live/example.com/privkey.pem;

And another one for ssl params:
vim /etc/nginx/snippets/ssl-params.conf

ssl_protocols TLSv1 TLSv1.1 TLSv1.2;
ssl_prefer_server_ciphers on;
ssl_ciphers "EECDH+AESGCM:EDH+AESGCM:AES256+EECDH:AES256+EDH";
ssl_ecdh_curve secp384r1;
ssl_session_cache shared:SSL:10m;
ssl_session_tickets off;
ssl_stapling on;
ssl_stapling_verify on;
resolver 8.8.8.8 8.8.4.4 valid=300s;
resolver_timeout 5s;
add_header X-Frame-Options DENY;
add_header X-Content-Type-Options nosniff;

Update nginx config (this will allow both http and https):
vim /etc/nginx/sites-available/default

server {
    listen 80 default_server;
    listen [::]:80 default_server;
    listen 443 ssl http2 default_server;
    listen [::]:443 ssl http2 default_server;

    server_name example.com www.example.com;
    include snippets/ssl-example.com.conf;
    include snippets/ssl-params.conf;
...

Automate certificate renewal:
crontab -e

15 1 * * * /usr/bin/certbot renew --quiet --renew-hook "/bin/systemctl reload nginx"
20 1 * * * nginx -s reloadv

The above will run at 1:15 am every day, then reloads nginx config at 1:20 am.

To view certs expiration dates:

apt-get install  ssl-cert-check
ssl-cert-check -c /etc/letsencrypt/live/example.com/cert.pem

Additional Mac Setup

brew install ssh-copy-id
ssh-copy-id [email protected]
This will allow you to ssh without a password the next time you ssh.

Useful logs

cat /var/log/redis/redis-server.log
sudo cat /var/log/fail2ban.log
sudo cat /var/log/nginx/error.log

fail2ban grouped by IP:

awk '($(NF-1) = /Ban/){print $NF}' /var/log/fail2ban.log | sort | uniq -c | sort -n

Useful monitoring commands

Ram usage:
free -m
top

Space:
df -ah
du -hs * | sort -h

Another way to get space info
apt-get install ncdu
ncdu /

Network activity:
netstat -tulpn

Linode ipv6 issue

If you can’t get apt-get to work, try to update /etc/gai.conf and uncomment line 54: precedence ::ffff:0:0/96 100

Linode Monitoring – Longview

Linode also provides Longview – web UI to access your server stats. The free version is limited to the last 24 hours.
Here is the official guide
I had to update iptables rules and restart the longview service:

iptables -I INPUT -s longview.linode.com -j ACCEPT
iptables -I OUTPUT -d longview.linode.com -j ACCEPT 
sudo service longview restart

Useful links:

Now, while it’s fun figuring these things out, git push heroku master sounds a lot easier.

Categories: Rails, Ruby

Setting up Personal VPN Server

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This is my second attempt at setting up a VPN service. This this time with lessons learned.
Server provider: RamNode
Price: $3/month
Virtualization: KVM
Specs: 512 GB RAM, 10 GB Storage, 1000 GB Bandwidth
Chosen OS: CentOS 7

After you set up your server, ssh into it.

Optionally, install and enable firewall for better security. Better to do before you run the vpn script. Otherwise, will have to manually update firewall rules.

yum update
# If you want vim:
yum search vim
yum install vim-enhanced.x86_64
yum install firewalld


systemctl enable firewalld
systemctl start firewalld

#Show configuration for the given zone:
firewall-cmd --zone=public --list-all

# add a port for your ssh console. Recommended to change from default 12
firewall-cmd --add-port 1234/tcp
firewall-cmd --add-port 1234/tcp --permanent
vim /etc/ssh/sshd_config
# update Port to 1234 (or whatever you picked above)
# Uncomment Protocol 2 - it provides better security
service sshd restart


# this retrieves the vpn script - see https://github.com/Nyr/openvpn-install
wget https://git.io/vpn -O openvpn-install.sh && bash openvpn-install.sh


# if you plan to run VPN on port 443
firewall-cmd --zone=public --add-port=443/udp
firewall-cmd --permanent --zone=public --add-port=443/udp
vim /etc/openvpn/server.conf
#add "port 443" or change to 443 if there is already an entry

#in the generated .ovpn file make the same change for the port
# should look something like this: remote your_server_ip 443


# additional security feature (not necessary for VPN)
yum install epel-release
yum install fail2ban
yum install fail2ban-systemd
cp -pf /etc/fail2ban/jail.conf /etc/fail2ban/jail.local
systemctl enable fail2ban
vim /etc/fail2ban/jail.local
#set to somehting like this
------------------------
[DEFAULT]
# ban hosts for 300 seconds:
bantime = 300
maxretry = 2

[sshd]
port = your_ssh_port
enabled = true

#Override /etc/fail2ban/jail.d/00-firewalld.conf:
banaction = iptables-multiport


#if SELinux is enabled (check with sestatus)
[selinux-ssh]
port     = ssh
logpath  = %(auditd_log)s
enabled = true


#Check logs:
/var/log/fail2ban.log
------------------------
systemctl restart fail2ban



# if you need more users, just execute the script again
sh openvpn-install.sh

This generates a single some_name.ovpn file that you can download and use with an OpenVPN client. Hopefully, you now have a personal VPN server for roughly $30 a year.

Disabling ipv6
If you’re not planning on using ipv6, may as well disable it. Unfortunately fail2ban doesn’t support it yet.

sysctl -w net.ipv6.conf.all.disable_ipv6=1
sysctl -w net.ipv6.conf.default.disable_ipv6=1

Multiple instances of OpenVPN

If you want to run multiple instances of vpn (say a typical 1194 udp and another one on 443 tcp to avoid blocking)
Add a new config in /etc/openvpn
For simplicity, you can copy existing server.conf and lets name it server2.conf.

Update server2.conf to use a different port and change the server ip (let’s say if original server.conf has ip of 10.8.0.0, let’s give the new config
10.8.2.0:

port 443
proto tcp
server 10.8.2.0 255.255.255.0

Start your new openvpn instance:

systemctl start [email protected]_443_tcp

If using firewalld, add new rules:

firewall-cmd --zone=trusted --add-source=10.8.2.0/24
firewall-cmd --permanent --zone=trusted --add-source=10.8.2.0/24
firewall-cmd --direct --add-rule ipv4 nat POSTROUTING 0 -s 10.8.2.0/24 -j SNAT --to your_server_ip
firewall-cmd --permanent --direct --add-rule ipv4 nat POSTROUTING 0 -s 10.8.2.0/24 -j SNAT --to your_server_ip

Restart your new openvpn server:

systemctl restart [email protected]_443_tcp

If you’d like to use the same .ovpn config on the client side to connect to both ports, add this to client config:

server-poll-timeout 4
remote your_ip 1194 udp
remote your_ip 443 tcp
remote your_ip 1194 udp
remote your_ip 1194 udp

This will try to connect to 1194 udp first, then if unsuccessful, it’ll try 443 tcp, then 1194
In order for this to work, both configs on the server must have the same settings (except for IP’s of course)

OpenDNS
If using OpenDNS head to https://dashboard.opendns.com/ and set it up

Auto-update all CentOS packages

yum -y install yum-cron

vim /etc/yum/yum-cron.conf
# set:
# download_updates = yes
# apply_updates = yes
sudo systemctl enable yum-cron.service
systemctl start yum-cron

Harden SSH
vim /etc/ssh/sshd_config

Ciphers aes128-ctr,aes192-ctr,aes256-ctr
KexAlgorithms ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256
MACs hmac-sha2-256,hmac-sha2-512

A nice resource to test the speed: https://speedof.me/.

Categories: Security

Phoenix and Ecto. First Steps

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Valid as of Phoenix 1.2

Show routes:
mix phoenix.routes

Generating resources:
mix phoenix.gen.html Post posts –no-model
mix phoenix.gen.json Post posts

Ecto
Types

  • :string
  • :integer
  • :map
  • :binary_id
  • :float
  • :boolean

Writing Queries
Two ways

  1. Query
    import Ecto.Query
    
    from p in context.Posts
    where p.Title.Contains("Stuff")
    select p;
    
  2. Expression
    MyApp.Post
    |> where(titlle: "Stuff")
    |> limit(1)
    

Making changes – https://hexdocs.pm/ecto/Ecto.Changeset.html
changeset = Post.changeset(post, %{title: “updated”})
Repo.update(changeset)
Repo.delete(post)

Migrations
Generate migration:
mix ecto.gen.migration [migration_name] -r [repo]

Generate schema:
mix phoenix.gen.model [Schema] [table] [fields] -r [repo]

Run/Rollback migration
mix ecto.migrate -r [repo]
mix ecto.rollback -r [repo]

Generate migration:
Does not generate schema module:
mix ecto.gen.migration [migration_name] -r [repo]

Generates both schema model and a migration:
mix phoenix.gen.model [Schema] [table] [fields] -r [repo]

To avoid specifying repo all the time:
config :my_app, ecto_repos: [MyApp.Repo]

Categories: Elixir, Phoenix, Uncategorized

Starting with Phoenix. Installation.

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Prerequisites (valid as of Phoenix 1.2)

Mac

  • Elixir – brew install elixir
  • node – brew install node
  • Postgres – Postgres.app

Windows
For Windows, can use Chocolatey to install node and Elixir. Postgres seems to be outdated as of time of this post. Or download from source and install:

Add to Windows path PostgreSQL (dependent on PostgreSQL version), so we can use psql on command line –
C:\Program Files\PostgreSQL\9.6\bin
C:\Program Files\PostgreSQL\9.6\lib

Install phoenix:

$ mix archive.install https://github.com/phoenixframework/archives/raw/master/phoenix_new.ez

Alternatively, download a specific version from https://github.com/phoenixframework/archives.

Generate and run a new project:

$ mix phoenix.new my_first_app
$ mix ecto.create
$ npm install
$ iex -S mix phoenix.server
iex> :observer.start

Categories: Elixir, Phoenix

Developing a Simple app with Action Cable and Devise on Heroku

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As I continue to learn Rails, this is my experience developing a Rails application using Action Cable (allows communication using web sockets)

Finished product: Story Estimate

Assuming we already generated a new Rails app, lets start with authentication using Devise gem.
Add “gem ‘devise'” to your gem file.

Run a few commands to generate your users:
$ rails generate devise:install
$ rails generate devise User
$ rails generate devise:views
$ rails db:migrate

For the sake of this application, I want to enable guest users. Lets allow that:

class ApplicationController < ActionController::Base
  protect_from_forgery with: :exception

  def current_or_guest_user
    current_user || guest_user
  end

  # find guest_user object associated with the current session,
  # creating one as needed
  def guest_user(with_retry = true)
    # Cache the value the first time it's gotten.
    @cached_guest_user ||= User.find(session[:guest_user_id] ||= create_guest_user.id)

  rescue ActiveRecord::RecordNotFound # if session[:guest_user_id] invalid
    session[:guest_user_id] = nil
    guest_user if with_retry
  end

  private

  def create_guest_user
    u = User.create(email: "guest_#{Time.now.to_i}#{rand(100)}@example.com")
    u.save!(validate: false)
    session[:guest_user_id] = u.id
    u
  end
end

Now, if we want to sign in a user as a guest, we’d call sign_in(current_or_guest_user)

Next thing, we want to authorize our Action Cable connections with Devise users. In order to do that, we need to add some hooks in the config/initialazers. This will add current user id to user’s cookie:

config/initialazers/warden_hooks.rb

Warden::Manager.after_set_user do |user,auth,opts|
  scope = opts[:scope]
  auth.cookies.signed["#{scope}.id"] = user.id
end

Warden::Manager.before_logout do |user, auth, opts|
  scope = opts[:scope]
  auth.cookies.signed["#{scope}.id"] = nil
end

With this, we can configure rails connection:

module ApplicationCable
  class Connection < ActionCable::Connection::Base
    identified_by :current_user

    def connect
      self.current_user = find_verified_user
    end

    protected
      def find_verified_user
        if verified_user = User.find_by(id: cookies.signed['user.id'])
          verified_user
        else
          reject_unauthorized_connection
        end
      end
  end
end

Now, time to generate a new channel:
rails g channel channel_name optional_method
It may look someting like this:

class CoolChannel < ApplicationCable::Channel
  BASE_CHANNEL = 'BaseChannel'.freeze

  def subscribed
    stream_from "#{BASE_CHANNEL}#{params['some_key']}"
  end

  def unsubscribed
    # Any cleanup needed when channel is unsubscribed
  end

  def some_action(data)
    value_from_client = data['value_0']
    ActionCable.server.broadcast\
      "#{BASE_CHANNEL}#{data['some_key']}",
      data
  end
end

This will create a new custom-named channel based on whatever we want to send in params from the client. some_action is the method that will be called by the clients to send a message. In this case we just rebroadcast the message to all clients.

To make a call from the client to the server, go to the .js or .coffee file for the earlier generated channel (should be in javascripts/channels). We can call back to the server:

jQuery(document).on 'turbolinks:load', ->
  session_slug = $('#session_slug').val()
  player_name = $('#player_id').val()
  $stats =$('#statistics')

  App.estimation_session = App.cable.subscriptions.create {
    channel: "CoolChannel",
    },
    connected: ->

    disconnected: ->
      # Called when the subscription has been terminated by the server

    received: (data) ->
      value_from_server = data.value_0

    some_action: (value_0, value_1)->
      @perform 'some_action',
               value_0: value_0,
               value_1: value_1

When deploying to Heroku, we need to Add Redis To Go add-in (or any other Redis add-in such as Heroku Redi. Then update cable.yml to use redis:
adapter: redis
url: YOUR_URL

To find Redis connection URL, run:
heroku config | grep redis

Also, we need to add redis gem:
gem ‘redis’, ‘~> 3.2’

git push heroku master

Some useful resources:

Categories: Rails, Ruby

Ruby Inheritance Rules Simplified

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A simple principle to understand Ruby inheritance is LIFO (Last In First Out).

 

  1. Ruby will search the object you’re calling it from
  2. It will search it in any included modules, starting with the last loaded module
  3. It will go in the superclass (technically, modules get in the inheritance hierarchy as well, but whatever)

When the method is found, the search stops.

 

A Note About Calling super.
The same rule applies if you use super. If you have the same method defined in both module and a parent class, the module method will be called.
Here’s a simple example:

module Test
  def abc
    puts 'abc from Module'
  end
end

class TestClassParent
  def abc
    puts 'abc from parent'
  end
end

class TestClassChild &amp;lt; TestClassParent
  include Test

  def abc
    super
  end
end


TestClassChild.new.abc

Running this will result in:

abc from Module

Categories: Ruby

Debugging Rails

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Install pry, pry-byebug, and pry-rails gems.
To add a breakpoint, type binding.pry wherever you want your breakpoint to happen.
In console use coninue, step, next, finish commands:

step: Step execution into the next line or method. Takes an optional numeric argument to step multiple times.

next: Step over to the next line within the same frame. Also takes an optional numeric argument to step multiple lines.

finish: Execute until current stack frame returns.

continue: Continue program execution and end the Pry session.

To add shortcuts to ^ commands, add to ~/.pryrc:
Pry.commands.alias_command ‘c’, ‘continue’ rescue nil
Pry.commands.alias_command ‘s’, ‘step’ rescue nil
Pry.commands.alias_command ‘n’, ‘next’ rescue nil
Pry.commands.alias_command ‘f’, ‘finish’ rescue nil

Categories: Rails, Ruby

Setting Up My Mac Dev Environment

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Set up a package manager: Homebrew

Istall iterm2

ZSH

Replace bash with zsh (it offers some nice plugins and themes).

brew install zsh zsh-completions

Install oh-my-zsh – “A delightful community-driven (with 1,000+ contributors) framework for managing your zsh configuration.”

sh -c "$(curl -fsSL https://raw.githubusercontent.com/robbyrussell/oh-my-zsh/master/tools/install.sh)"

To update oh-my-zsh, run upgrade_oh_my_zsh in zsh shell.

Pick your set of plugins (edit .zshrc file):
plugins=(git brew gem ruby rvm rails yarn npm)

Pick a theme (.zshrc):

ZSH_THEME="af-magic"
If you're on OSX Sierra, then you need another step:
create ~/.ssh/config with this content:
Host *
  UseKeychain yes
  AddKeysToAgent yes
  IdentityFile ~/.ssh/id_rsa

Generate github SSH Keys – https://help.github.com/articles/generating-a-new-ssh-key-and-adding-it-to-the-ssh-agent/

Add generated ssh key to your keychain, so you don’t have to reenter your ssh passphrase:

 ssh-add -K ~/.ssh/id_rsa 

Rails/Ruby/RVM/rbenv

If using rvm with zsh, add this to your .zshrc:

[[ -s "$HOME/.rvm/scripts/rvm" ]] && . "$HOME/.rvm/scripts/rvm"

If you use rbenv, you may need to add this to your .zshrc:

export PATH="$HOME/.rbenv/shims :$PATH"
eval "$(rbenv init -)"

Exercism

For exercism zsh completions, add

if [ -f ~/.config/exercism/exercism_completion.zsh ]; then
. ~/.config/exercism/exercism_completion.zsh
fi

And run

$ mkdir -p ~/.config/exercism/
$ curl http://cli.exercism.io/exercism_completion.zsh > ~/.config/exercism/exercism_completion.zsh

git standup

git-standup

brew install git-standup

fzf is a general-purpose command-line fuzzy finder

https://github.com/junegunn/fzf#key-bindings-for-command-line

brew install fzf
# Install shell extensions
/usr/local/opt/fzf/install

autojump – a faster way to navigate your filesystem

https://github.com/wting/autojump

brew install autojump

# add autoload to .zshrc
[[ -s $(brew --prefix)/etc/profile.d/autojump.sh ]] &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp; . $(brew --prefix)/etc/profile.d/autojump.sh

fkill – Fabulously kill processes

https://github.com/sindresorhus/fkill-cli
https://github.com/SamVerschueren/alfred-fkill

npm install --global fkill-cli
npm install --global alfred-fkill

Mac apps

Git alias (add to .gitconfig)

Show recent branches:
[alias]
recent = “for-each-ref –sort=-committerdate –count=10 –format=’%(refname:short)’ refs/heads/”

Python

Install Anaconda – https://www.anaconda.com/distribution/#download-section

Update your .bashrc or .zshrc with

export PATH="$HOME/anaconda3/bin:$PATH"

Categories: Development Setup, git

Deploying Rails App to Heroku

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My first experience installing a Rails app on Heroku. A pretty easy way to deploy Rails apps.

If you made any changes to your gemfile, make sure to run
bundle install –without production
Even if you already have all of the gems installed. This updates Gemfile.lock, which will be used by Heroku.

If you are on Windows, make sure to remove “.exe” from bundle, rails, and rake inside of your bin folder:
#!/usr/bin/env ruby.exe

Create a free account on Heroku if you don’t have one yet. Download the Heroku Toolbelt.
From the command line:

heroku login
cd path_to_you_app
heroku create

This will create a new Heroku application and set up the remote Git repo. You can optionally specify a name for your app in “heroku create” command, or you can rename it later.

Now, lets push the code to Heroku and run all the DB commands if necessary:

git push heroku master
heroku run rake db:migrate
heroku run rake db:seed
heroku open

To update you app, just push to heroku master.

To get information about your Heroku apps:

heroku apps
heroku ps
heroku logs
heroku run console

The last command will launch a remote Rails console session.

To rename your app:
heroku rename new_name

To destroy your app:
heroku destroy app_name

Categories: Rails

Starting with RSpec in Rails

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Add RSpec related gems to gemfile:

group :development, :test do 
  gem 'rspec-rails'
end

group :test do
  gem "capybara"
end

Capybara is a framework for testing web applications; allows to navigate your app programmatically.

Install your RSpec gems: bundle install

Generate RSpec templates:
generate rspec: rails g rspec:install

To view all available generators: rails g

Since RSpec uses test database, run your migrations for test environment:
rails db:migrate RAILS_ENV=test
If this is the first run, may need to set up the database by running RAILS_ENV=test rake db:reset

To run all specs: rspec
To add formatting: rspec -format doc (or use shortcut: rspec -f doc)
To always use the same formatting, add -format doc to .rspec file.

To use helper files for RSpecs
Uncomment this line in rails_helper.rb:
Dir[Rails.root.join(‘spec/support/**/*.rb’)].each { |f| require f }
And place all your helper methods inside of spec/support directory.

Sample RSpec file:

require 'rails_helper'

describe 'Navigating movies' do
  it 'allows navigation from the detail page to the listing page' do
    movie = Movie.create(movie_attributes)

    visit movie_url(movie)

    click_link 'All Movies'

    expect(current_path).to eq(root_path)
  end
Categories: Rails, Ruby