How to Install Ruby On Rails on Mac - Updated

This post will guide you to prepare your Mac OS to install Ruby on Rails using rvm. It will also show you how to create a sample rails app to enjoy all the efforts involved in installation.

There is a good news and a bad news. First the good news. Ruby comes preinstalled on all Mac's.
To check which version you have, open up Terminal and type

$ ruby -v

The most current version as of July 2012 is 1.9.3.
Now the bad news, the version you have may not be the version you want and it's a pain to manage different ruby versions manually. Ruby Version Manager (rvm) does great job so it carry the burden of installing and managing different versions.

Step 0. Install git and gcc 

To check if you already have git, inside Terminal run this command

$ git --version

If you don't have git installed, download the recent installer from
http://code.google.com/p/git-osx-installer/downloads/list?can=3
Open the .dmg file and you will find the installer package. Follow the instructions to install git.

Ruby is compiled locally using gcc, hence make sure you have gcc installed.

$ gcc --version

Gcc does not come preinstalled on Mac. You need a developer account to install it separately.

• If you are running Lion, login using Apple ID and download Apple's official Command Line Tools for Xcode. Simply double click .dmg file and then the enclosed .pkg file to start the installation process. 
• If you on Snow Leopard, you can download Xcode (4 GB in size) and install it, which includes gcc. The easier option would be to download the unofficial Gcc compiler and related tools from osx-gcc compiler downloads page.

Step 1. Install RVM

Open up Terminal and execute this command -

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

It downloads and runs RVM installation script.

If curl complains about certificates, try with -k option

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

If you run into other issues, make sure you have git installed. Don't worry, it's easy to setup.

Once rvm installtion is completed it shows the files it modified. rvm is now ready to be used. Close the current Terminal window and open a new one. Test rvm using

 $ rvm --version

You should see a version number with no errors. In case it was not recognized as a command you will have to load the rvm script into the shell so that shell can recognize 'rvm' as a valid command. You do that by executing following command verbatim.

$ echo '[[ -s "$HOME/.rvm/scripts/rvm" ]] && "$HOME/.rvm/scripts/rvm" ' >> ~/.bash_profile

Step 2. Install Ruby using rvm
We will install 1.9.3 as part of this tutorial. To get a feel of what rvm is capable of installing, run this command

 $ rvm list known

It lists different versions of Ruby packages that can be installed and managed by rvm.
To install ruby use this format rvm install for example, 

 $ rvm install 1.9.3

It downloads the source code for ruby 1.9.3 and then compiles it locally. If there are any errors, rvm will also tell you how to fix them. Once done, it displays "Install - #complete"

To verify, list the installed versions using

 $ rvm list

It should list the installed version like this -

~$ rvm list

rvm rubies

 * ruby-1.9.3-p194 [ x86_64 ]

# => - current
# =* - current && default
#  * - default

and now to double check, verify the ruby version itself using

 $ ruby -v

Now set it as your default ruby version.

 $ rvm --default 1.9.3

Optionally, you might want to generate Ruby core documentation by running

 $ rvm docs generate

Step 3. Install Rails and other Gems
It's simple. Run this command and it will install rails and all other dependencies which work with your ruby version. It also install the docs for al the gems. Takes some time ...

 $ gem install rails

To install SQLite 3, first verify you have sqlite3 installed on your system by typing

 $ sqlite3 -version

It will respond with a long version string. Now install ruby binding for sqlite using

 $ gem install sqlite3

Step 4. Ruby On Rails Test Drive
Now that you have all the required components in place, let's create a your first Ruby on Rails app to make sure everything is working smoothly. Again inside a Terminal window,  navigate to a directory where you want to create your new app. ~/rails-app for example. Run these commands one by one

$ rails new todos

This will create the template application with model, view and controller and some static files.

$ cd todos

Tell rails to generate scema for your todos app database and also generate controller and views for standard actions.

$ rails g scaffold todo name:string completed:boolean

Run database migration

$ rake db:migrate

Then tart the rails WEBrick server on default port 3000

$ rails s

Finally, point your browser to http://localhost:3000/ If you see a welcome page, your app is running fine. Congratulations! Your todos can be managed at http://localhost:3000/todos

When you are done, you can stop the server by typing CTRL+C in the shell window where you started it earlier.

Extra Credit: More rvm commands

To revert to system version of ruby, i.e. pre-rvm ruby use this,

$ rvm system

To go back to 1.9.3 or any other version, use

$ rvm 1.9.3

To get the list of all rvm commands,

$ rvm usage

Hope it helped!

Sublime Text 2 - I'm loving it!

Leaving Notepad++ was not easy. The recommendation for TextMate was loud and clear. But it didn't impress me and the search continued. There came this new kid on the block - Sublime Text 2. I must say it's really Sublime. If you haven't tried yet, download it now - http://www.sublimetext.com/2 Not just mac users, but my ubuntu friends are also leaving their "vi" and gEdit for Sublime Text 2.

My favorite features -

• multiple cursors - it's incredibly useful!
• column select
• crazy fast file switching - include 'Go to anything' search (cmd + p)
• context specific search and replace
• side by side multi-pane editing (like :vsp in vim)
• auto completion 
• bookmarks (like in vim)
• distraction free mode
• Snippet support 
• Zen coding support 

And there is a package manager which makes installing new packages a piece of cake.

Terminal command to open up Sublime Text 2
It's simple, just create s symlink and add it to your PATH

ln -s "/Applications/Sublime Text 2.app/Contents/SharedSupport/bin/subl" ~/bin/subl

Edit your ~/.bashrc or ~/.bash_profile to add this -

PATH=$PATH:~/bin
export PATH

Install package manager-

Open Sublime text 2, you can use subl command in your Terminal now.
Open the console by clicking View -> Show Console  and paste this in the console and hit enter. import urllib2,os; pf='Package Control.sublime-package'; ipp=sublime.installed_packages_path(); os.makedirs(ipp) if not os.path.exists(ipp) else None; urllib2.install_opener(urllib2.build_opener(urllib2.ProxyHandler())); open(os.path.join(ipp,pf),'wb').write(urllib2.urlopen('http://sublime.wbond.net/'+pf.replace(' ','%20')).read()); print 'Please restart Sublime Text to finish installation'
Restart Sublime Text 2 to complete the installation process.
Presse cmd + shift + p to access the command pallet and then type 'Install packages" and hit Enter.
This will open up a list of all available packages. Select the package from the list and Enter. That's it. It will download the package and install it for you.

Here is the list - http://wbond.net/sublime_packages/community

A very quick way to create new folders and file - cmd + alt + n -
Happy Coding!

Print Screen in Mac

When I opened my macbook, the first thing I wanted to do was to take a screenshot and email it to my friend. But there is no Print Screen? First Google result - cmd + shift + 3. Can it be more obscure? 

Sure, it has lot of good functionality built in but a dedicated key or fn+something is more user friendly, isn't it?

Here are all options - 

• Cmd + shift + 3 -- Takes screenshot of the entire screen and saves it as a .png on the desktop
• Cmd + shift + 4 -- Lets you select an area and then saves it as a .png on the desktop
• Cmd + shift + 4 + space -- Lets you take a screenshot of just one window. and saves it as a .png on the desktop

To copy the contents to the clipboard, add control key with above combinations. e.g 

• Cmd + +ctrl + shift + 3 -- Takes screenshot of the entire screen and saves it to the clipboard

Command Line -

For Terminal lovers, screencapture command can be used and it's especially useful for automated scripts. 

$ screencapture -iW ~/Desktop/screen.jpg

File Format 

Mac OX X 10.4 and later versions use .png as a default file format to save the screenshot but this can be changed by using the below command inside Terminal

$ defaults write com.apple.screencapture type image_format

$ killall SystemUIServer

where image_format can be jpg, tiff, pdf, png, bmp or pict. The second command causes SystemUIServer to restart so that the change takes effect immediately. 

There is also a native app - 

If you don't like so many keys for just a screenshot, you can also use an app called Grab, bundled by Apple by default, to grab a screenshot and view it using Preview application

So much for a simple print-screen!