Installing RoR 3.x on Ubuntu 10.4 with MySQL

I'm writing this as a reminder for myself.
To install Rails (3.x) on Ubuntu 10.4 with a MySQL gem do the following:


sudo su
apt-get install build-essential
apt-get install ruby rdoc libopenssl-ruby
wget http://production.cf.rubygems.org/rubygems/rubygems-1.3.7.tgz
tar zxvf rubygems-1.3.7.tgz
cd rubygems-1.3.7
ruby setup.rb
ln -s /usr/bin/gem1.8 /usr/local/bin/gem
sudo apt-get install ruby1.8-dev
gem install rails

To install the MySQL gem: 

apt-get install ruby-dev libmysql-ruby libmysqlclient-dev

gem install mysql

After creating the application using
rails new myApplicationName -d mysql
Running the rake db:migrate will result in error, since it requires a JS engine.
To fix that, edit the Gemfile in the application directory and add the following lines:


gem 'execjs'
gem 'therubyracer'

and then run
bundle install

* Another option is to install NodeJS on the machine, as the javascript engine by following these steps:

sudo apt-get install python-software-properties
sudo add-apt-repository ppa:chris-lea/node.js
sudo apt-get update
sudo apt-get install nodejs npm

.

Flex Debugging Not Working on Chrome w7

The solution is here

Mysql2::Error (Invalid date: xx) on a text field?!

I have this rule, the longer it takes to figure out a bug, the dumber the solution is going to be. This one was no exception.This bug on the rails adapter for mysql (the native Mysql2 for Windows) cost me a day and a half of bewilderment.


The symptoms were that when populating a particular field in a table caused the created_at filed that was directly after to corrupt.
Although the entry would save successfully, once i tried to retrieve it, it would omit an argument error, without  any explanations  or indication to the field that was causing the problem.

After literally hours spent reinstalling and reconfiguring and redeploying my application and the run times involves i stumbled upon this error "Mysql2::Error (Invalid date: xx)" where xx was the text value of the field preceding the "created_at" standard field.
A quick search on Google pointed me to the bug in Mysql2.

My solution was (cross my heart and hope to die) was to add an extra field that i never populate before the date fields.

Good Luck.

Switching between Ruby Runtime versions on Windows

A nice tool for switching between ruby versions on windows is the pik gem
To use it, run gem install pik
Install locally by running: pik_install C:\pik
And add the installation dir (in this case c:\pik) to your system path.
Once you have that set up, you add ruby installations by running pik add C:\Ruby192\bin
and switch between them by pik 192

Running Rails 3.x with mysql2 on Windows

Every time I have to set up Ruby & Rails with MySQL on windows its the same old drag.

The easy part goes like this:
Installing Ruby 1.9: download ruby installer
Installing gem:  follow gem installation instructions
Install MYSQL: I like using the WAMP server, but its also possible to go for the MySQL regular installation
and:
Install Rails 3.x: run gem install rails

But then you will need to:
Install mysql2 by running gem install mysql2 -v 0.2.6
and
Copy libmySQL.dll from mysql bin to ruby-home/bin
This is downloadable from http://www.mysql.com/downloads/connector/c/

Now generate and run your server.
Don't forget to configure your database.yml file

Note: that if when sunning the server, it responds like:
Could not find gem 'mysql2 (~> 0.2.11)' in any of the gem sources listed in your Gemfile
Then go into your server root directory and open up the Gemfile
substitute the line:
gem 'mysql2', '~> 0.2.11'
with
gem 'mysql2', '~> 0.2.6'

...And your good to go.

Ruby 1.8.7 CSV parser workaround

Apparently there is some kind of problem when using the CSV parser for particular text structures. I want able to determine the exact cause of this problem expect that for some csv structures, the parse process result in an error.

In my frustration I resorted to write my one parser that is implemented as following:

 def self.parse(text)
    rows=text.split("\r")
    res=[]
    rows.each{|row|
      res << row.split(",")
    }
    res
  end
And amazingly enough, that's what did the trick.

Independent on Sundays.