How to Setup Development Environment to Contribute to Rails

Use the Rails Dev Box available at : https://github.com/rails/rails-dev-box

How to store array in mysql database in a Rails project

1. The column type should be text
2. serialize the column. In the active record class : serialize :your_field
3. Book.new(:your_field => [1,2])

How to limit svn log output to a given number of entries

Use limit option: svn log -l 5

Correction to Example in Ruby Programming Language

In Ruby 2.0, I had to make changes to the given code in the book:

birthyear = 1975

generation = case birthyear
    when 1946..1963 then "Baby Boomer"
    when 1964..1976
      "Generation X"
    when 1978..2000
      "Generation Y"
    else nil
    end

p generation

How to use VCR, Webmock with RSpec

1. Add the gems to the Gemfile under test group:
gem "webmock"
gem "vcr"

2. bundle

3. require 'vcr' as the first line in spec_helper.rb

4. Add

VCR.configure do |c|
  c.cassette_library_dir = 'spec/fixtures/cassettes'
  c.hook_into :webmock
  c.ignore_localhost = false
  c.allow_http_connections_when_no_cassette = true
end

inside the configure block.

5. Add WebMock.allow_net_connect! in the before block in the specs.
6. Wrap your network calls using :
       VCR.use_cassette do
              controller code that accesses network goes here
        end

Two different ways to execute a block

It is familiar that you will see yield being used when the block is anonymous and block.call being used when the block is explicit in the list of parameters for the method. Actually, you can use yield even when the block is explicitly passed to the method:

def foo(&block)
  yield
  block.call
end

foo { puts 'hi hey again' }

Setting two spaces as the default in Sublime Text 2

{
    "tab_size": 2,
    "translate_tabs_to_spaces": true
}

Save this in the Preferences -> Settings - Default file.

Installing Guest Additions on Ubuntu 12.04

1. sudo apt-get install virtualbox-guest-additions-iso
2. Boot the guest OS inside Virtualbox
3. In the virtual box menu, use Devices -> Install Guest Additions.

Reference: ubuntuforums.org

uninitialized constant ActiveSupport::Dependencies::Mutex (NameError)

This happens when creating a new project in Rails 2.3.8 if the Ruby gems version is 1.8.24.
Solution:

gem update --system 1.5.3

Now, rails blog will create a new project. 

program rails is not installed ubuntu rvm rails 2.3.8

1. Type : gem env, look at the  EXECUTABLE DIRECTORY value

2. Add the path to that directory to ~/.bashrc:
PATH="${PATH}:/home/your-user-name/.rvm/gems/ruby-1.8.7-p299/bin"


3. Open a new terminal

4. Type : rails -v



You will now see that rails command is recognized.