Rails Cheat Sheet

1. Create rails application

$ rails new demo

2. Examine installation

$ cd demo
$ rake about

3. Start the application

$ rails server

4. Create a controller and actions

$ rails generate controller Say hello goodbye
$ rails generate controller Store index

5. Generate a scaffold

$ rails generate scaffold Product title:string description:text image_url:string price:decimal
$ rails generate scaffold_controller LdapUsers  # generate only controller and views, say if model had been predefined.

With relationships

$ rails generate scaffold LineItem product:references cart:belongs_to

Destroy just created scaffold

$ rails destroy scaffold LineItem

6. Apply the migration

$ rake db:migrate

7. Run the tests

$ rake test
$ rake test:models - only the models directory

8. Populate table with test data

$ rake db:seed

9. Rollback the migration

$ rake db:rollback

10. Open up rails console

$ rails console
$ rails c

11. Add a column to a table

$ rails generate migration add_quantity_to_line_items quantity:integer

12. Create a migration

$ rails generate migration combine_items_in_cart

13. Clear the logs

$ rake log:clear LOGS=test

14. Create a mailer

$ rails generate mailer OrderNotifier received shipped

15. Create an integration test

$ rails generate integration_test user_stories

16. Generate documentation in HTML format. First modify README.doc then...

$ rake doc:app

17. See how much code is written

$ rake stats

18. Loading production db

$ rake db:setup RAILS_ENV="production"

19. Generate rake task

$ rails g task perfdb get_baselines
      create  lib/tasks/perfdb.rake

How to Install RVM, Ruby and Rails

For my reference:
http://yakiloo.com/using-rvm/
http://ryanbigg.com/2010/12/ubuntu-ruby-rvm-rails-and-you/
http://rvm.io/rvm/best-practices

For this installation I followed what’s called single user installation, which is the recommended way of installation, this is an isolated install within a user's $HOME, not for root.

Install RVM

1. Install prerequisites

$ sudo yum install sqlite-devel nodejs openssl

2. Set rvm_path

$ echo 'rvm_path="$HOME/.rvm"' >> ~/.rvmrc

3. Install RVM as a single user ( background info: https://rvm.io/rvm/install)

$  \curl -L https://get.rvm.io | bash -s stable

4. At this point, RVM should have been installed, check if rvm was installed correctly by loading it then checking it’s type:

$ source ~/.rvm/scripts/rvm
$ type rvm | head -n 1
rvm is a function

5. Make sure that the latest version is installed

$ rvm get stable

6. Run the rvm requirements to get all the dependencies for RVM, this might prompt for your password when it needed to install missing packages:

$ rvm requirements
Checking requirements for fedora.
Installing requirements for fedora.
Updating system
Installing required packages: patch, gcc-c++, patch, readline-devel, zlib-devel, libyaml-devel, libffi-devel, openssl-devel, autoconf, automake, libtool, bisondelacs password required for '/usr/bin/env PATH=/usr/local/bin:/bin:/usr/bin:/usr/local/sbin:/usr/sbin:/usr/local/bin/Aptana_Studio_3:/auto/home3/delacs/bin:/auto/home3/delacs/.rvm/bin:/sbin yum install -y patch gcc-c++ patch readline-devel zlib-devel libyaml-devel libffi-devel openssl-devel autoconf automake libtool bison': 
....................................................................................................................................................................................................................
Requirements installation successful.

Install Ruby

7. Now let’s install Ruby:

$ rvm install 2.0.0

8. The above command should install RubyGems with it, if in case there is an issue such that RubyGems was not able to install due to some checksum error, go to one version below the latest, e.g.,

$ rvm rubygems latest

9. Let’s tell RVM to use Ruby 2.0.0 as our default

$ rvm use ruby-2.0.0-p247 --default
Using /home/samdc/.rvm/gems/ruby-2.0.0-p247

10. Let’s check the version of Ruby in our environment

$ ruby -v
ruby 2.0.0p247 (2013-06-27 revision 41674) [x86_64-linux]

Install Rails

11. First, let’s set our gems environment, due to some contraints (I think it’s the corporate firewall preventing installation of certs) Add these lines to your ~/.gemrc:

:ssl_verify_mode: 0
:sources:
- http://rubygems.org/
- http://gems.github.com
gem: --no-rdoc --no-ri

The last line is to not install rdoc and ri

12. Let’s install Rails. We wan’t to make use of GemSets so we can easily manage versioning in our installs. Create a gemset:

$ rvm gemset create RailsDev
gemset created RailsDev => /auto/home3/delacs/.rvm/gems/ruby-2.0.0-p247@RailsDev

13. Let’s use that GemSet:

$ rvm gemset use RailsDev
Using ruby-2.0.0-p247 with gemset RailsDev

Let’s check if we are using that gemset

$ rvm gemset name
RailsDev

14. Now let’s install all gems that we need

$ gem install rails --version 4.0.1

15. Lets verify the installation

$ rails -v
Rails 4.0.1

16. To make use of this RVM environment, we can specify 2 files in the project’s root folder:

$ cat .ruby-gemset
RailsDev

$ cat .ruby-version
ruby-2.0.0-p247

To learn more about RVM and its environment, refer to these posts: http://yakiloo.com/using-rvm/ http://stackoverflow.com/questions/15708916/use-rvmrc-or-ruby-version-file-to-set-a-project-gemset-with-rvm

17. To make use of automatic install of rubies, you can specify a flag in ~/.rvmrc

rvm_install_on_use_flag=1

18. You also make bootstrapping a project happen via cd into the project directory, by adding this to ~/.rvmrc

export rvm_project_rvmrc=1

19. To access webrick from another system, firewall needs to be opened up for port 3000 as follows:

$ sudo firewall-cmd --permanent --zone=public --add-port=3000/tcp
$ sudo systemctl restart firewalld.service

Open up Firewall of Fedora Core 19

Here's the whole write up on FirewallD.
How you would open up http and https, or specific ports for your box:

$ sudo firewall-cmd --permanent --zone=public --add-service=http
$ sudo firewall-cmd --permanent --zone=public --add-service=https

Restart the firewall:

$ sudo systemctl restart firewalld.service

Or on specific ports:

$ sudo firewall-cmd --permanent --zone=public --add-port=9393/tcp

Restart the firewall:

$ sudo systemctl restart firewalld.service

How to Install RVM, Ruby and Sinatra

For my reference:
http://yakiloo.com/using-rvm/
http://ryanbigg.com/2010/12/ubuntu-ruby-rvm-rails-and-you/
http://rvm.io/rvm/best-practices

For this installation I followed what’s called single user installation, which is the recommended way of installation, this is an isolated install within a user's $HOME, not for root.

Install RVM

1. Set rvm_path

$ echo 'rvm_path="$HOME/.rvm"' >> ~/.rvmrc

2. Install RVM as a single user ( background info: https://rvm.io/rvm/install)

$  \curl -L https://get.rvm.io | bash -s stable

3. At this point, RVM should have been installed, check if rvm was installed correctly by loading it then checking it’s type:

$ source ~/.rvm/scripts/rvm
$ type rvm | head -n 1
rvm is a function

4. Make sure that the latest version is installed

$ rvm get stable

5. Run the rvm requirements to get all the dependencies for RVM, this might prompt for your password when it needed to install missing packages:

$ rvm requirements
Checking requirements for fedora.
Installing requirements for fedora.
Updating system
Installing required packages: patch, gcc-c++, patch, readline-devel, zlib-devel, libyaml-devel, libffi-devel, openssl-devel, autoconf, automake, libtool, bisondelacs password required for '/usr/bin/env PATH=/usr/local/bin:/bin:/usr/bin:/usr/local/sbin:/usr/sbin:/usr/local/bin/Aptana_Studio_3:/auto/home3/delacs/bin:/auto/home3/delacs/.rvm/bin:/sbin yum install -y patch gcc-c++ patch readline-devel zlib-devel libyaml-devel libffi-devel openssl-devel autoconf automake libtool bison': 
....................................................................................................................................................................................................................
Requirements installation successful.

Install Ruby

6. Now let’s install Ruby:

$ rvm install 1.9.3

7. The above command should install RubyGems with it, if in case there is an issue such that RubyGems was not able to install due to some checksum error, go to one version below the latest, e.g.,

$ rvm rubygems 2.1.8

8. Let’s tell RVM to use Ruby 1.9.3 as our default

$ rvm use ruby-1.9.3-p448 --default
Using /auto/home3/delacs/.rvm/gems/ruby-1.9.3-p448

9. Let’s check the version of Ruby in our environment

$ ruby -v
ruby 1.9.3p448 (2013-06-27 revision 41675) [x86_64-linux]

Install Sinatra

10. First, let’s first set our gem environment, due to some contraints (I think it’s our firewall preventing installation of certs) Add these lines to your ~/.gemrc:

:sources:
- http://rubygems.org/
- http://gems.github.com
gem: --no-rdoc --no-ri

The last line is to not install rdoc and ri

11. Let’s install Sinatra. We wan’t to make use of GemSets so we can easily manage versioning in our installs. Create a gemset:

$ rvm gemset create SinatraDev
gemset created SinatraDev => /auto/home3/delacs/.rvm/gems/ruby-1.9.3-p448@SinatraDev

12. Let’s use that GemSet:

$ rvm gemset use SinatraDev
Using ruby-1.9.3-p448 with gemset SinatraDev

Let’s check if we are using that gemset

$ rvm gemset name
SinatraDev

13. Now let’s install all gems that we need

$ gem install sinatra -v 1.4.3
$ gem install shotgun -v 0.9

14. To make use of this RVM environment, we can specify 2 files in the project’s root folder:

$ cat .ruby-gemset
SinatraDev
 
$ cat .ruby-version
ruby-1.9.3-p448

To learn more about RVM and its environment, refer to these posts: http://yakiloo.com/using-rvm/ http://stackoverflow.com/questions/15708916/use-rvmrc-or-ruby-version-file-to-set-a-project-gemset-with-rvm 15. To make use of automatic install of rubies, you can specify a flag in ~/.rvmrc

rvm_install_on_use_flag=1

16. You also make bootstrapping a project happen via cd into the project directory, by adding this to ~/.rvmrc

export rvm_project_rvmrc=1

17. To access webrick from another system, firewall needs to be opened up for port 9393 as follows:

$ sudo firewall-cmd --permanent --zone=public --add-port=9393/tcp
$ sudo systemctl restart firewalld.service

18. Start WEBrick using shotgun:

$ shotgun main.rb --host mymachine.domain.com

How to add Launcher in Gnome for Fedora 19

Create a .desktop file:

$ sudo vi /usr/share/applications/aptana-studio-3.desktop

Add this content:

[Desktop Entry]
Name=Aptana Studio 3
Exec=/usr/local/bin/Aptana_Studio_3/aptana
Icon=/usr/local/bin/Aptana_Studio_3/icon.xpm
Type=Application
Categories=Development

VNC Server Setup on Fedora 19

I followed this post to setup my VNC Server. Specific to my setup I had to update my /etc/systemd/system/vncserver@:1.service so that it will wait for autofs for my home directory:

After=syslog.target network.target autofs.service

Then I had to open up the ports for VNC as follows:

$ sudo firewall-cmd --permanent --zone=public --add-service=vnc-server

Bash Keyboard Shortcuts

Ctrl + A        Go to the beginning of the line you are currently typing on
Ctrl + E        Go to the end of the line you are currently typing on
Ctrl + L        Clears the Screen, similar to the clear command
Ctrl + U        Clears the line before the cursor position. If you are at the end of the line, clears the entire line.
Ctrl + H        Same as backspace
Ctrl + R        Let’s you search through previously used commands
Ctrl + C        Kill whatever you are running
Ctrl + D        Exit the current shell
Ctrl + Z        Puts whatever you are running into a suspended background process. fg restores it.
Ctrl + W        Delete the word before the cursor
Ctrl + K        Clear the line after the cursor
Ctrl + T        Swap the last two characters before the cursor
Esc + T         Swap the last two words before the cursor
Alt + F         Move cursor forward one word on the current line
Alt + B         Move cursor backward one word on the current line
Tab             Auto-complete files and folder names