Make sure that `gem install therubyracer -v '0.11.0'` succeeds before bundling.

1. brew install v8
2. bundle update

How to Create DNS Records using Linode API

dns = Fog::DNS.new(provider: 'linode',
                                    linode_api_key: 'your-linode-api-key-goes-here')
zone = dns.zones.create(domain: 'your-domain.com',
                 email: 'admin@your-domain.com')
zone.nameservers

Create a www version of your site and point to the right IP.
record = zone.records.create(value:  '1.2.3.4', name: 'your-domain.com', type: 'A')

To make www.your-domain.com go to the same place, use a cname record:
record = zone.records.create(value: 'your-domain.com', name: 'www', type: 'CNAME')

to_yaml method y broken in Ruby 1.9

vi ~/.irbrc
YAML::ENGINE.yamler = 'syck'
Save. Now you will be able to use the method y to dump objects in yaml format.

error: The following untracked working tree files would be overwritten by merge: Library/Formula/pbrt.rb

cd /usr/local
git reset --hard origin/master
brew update

Rails 3.2 Tagged Logging

MyLogger = ActiveSupport::BufferedLogger.new(Rails.root.join('log/my_tagged.log'))
MyTaggedLogger.tagged("PAY") { MyTaggedLogger.info "Hello I am working!" }

NoMethodError: undefined method `y' for main:Object

Rails 3.2.6 and Ruby 1.9.3 gives that error. Resolution: YAML::ENGINE.yamler = 'syck'

How to check how long a process has been running

ps -p 64622 -o etime=

PID is 64622
Format is as follows:
16-19:18:35
DD-HH:MM:SS

How to install local gem

1. Download the .gem file.
2. gem unpack file.gem .
. is the current directory
3. Specify in Gemfile:
   gem 'name-of-gem', '0.1.0', :path => "/path/to/the/unpacked/gem/directory"
4. bundle install

Turn off generating css.sass and js.coffee files

config.generators.stylesheets = false
config.generators.javascripts = false

in application.rb

Install Ruby 2.0 Preview 1 on Mac OS

$ brew install libyaml
$ rvm install ruby-2.0.0-preview1 --with-openssl-dir=$HOME/.rvm/usr --verify-downloads 1

Install a specific version of gems from a list of gems in a file

cat gems.txt | while read x; do rvm use @@global && gem install $x -v=2.3.8 ; done

find current time mysql

SELECT CURTIME();

Rails Error: Unable to access log file. Please ensure that

log/development.log exists and is chmod 0666. The log level has been raised to WARN and the output directed to STDERR until the problem is fixed.

Resolution: 

Change the line : config.log_level = Logger::INFO

    to : config.log_level = :info

in development.rb, production.rb etc.

List Just Directories Using ls in Unix

ls -ld */

constant ActiveSupport::Dependencies::Mutex (NameError)

Problem:
.rvm/gems/ruby-1.8.7-p299@global/gems/activesupport-2.3.8/lib/active_support/dependencies.rb:55: uninitialized constant ActiveSupport::Dependencies::Mutex (NameError)

Ruby gems version 1.8.14

Resolution:

Downgrade gems. gem update --system 1.5.3

The following SSH command responded with a non-zero exit status.

Problem:

The following SSH command responded with a non-zero exit status.
Vagrant assumes that this means the command failed!

mount -t vboxsf -o uid=`id -u vagrant`,gid=`id -g vagrant` v-root /vagrant

Resolution:

1. On your Mac:
$ vagrant gem install vagrant-vbguest
Since I installed Vagrant as a package (dmg) otherwise do : gem install vagrant-vbguest
2. vagrant up

The gem will automatically install the update. If VM is already running just do : vagrant halt

Reference:

Automatically download and install VirtualBox guest additions in Vagrant

Move to the end of the file in vi

$ then A

Upgrading GIT on Ubuntu 10.04

• sudo add-apt-repository ppa:git-core/ppa
• sudo apt-get update
• sudo apt-get install git

Notes from stackoverflow. This works.

Testing Cookies

Notes from Rails Cookbook:

To fully test cookies, you need to test that your application is not only setting the cookies, but also correctly reading them when passed in with a request. To do that create Cookie object and add that to the simulated test Request object, which is setup before every test in the setup method.

Rails cookie tests : https://github.com/rails/rails/blob/master/actionpack/test/dispatch/cookies_test.rb

Securing Your Server by Closing Unnecessary Ports

I am getting rid of Rails Cookbook dead tree copy I bought in 2007. Notes that are valid for any Rails version.

$ netstat -an

will list all network daemons and the ports they are listening on. This will not show you the service name. To find out do:

$ less /etc/services

This will list the service name and the port number it is running. Diable the service based on your Linux flavor and reboot server to make sure it does not get restarted automatically on reboot.