Rails Templates

Posted by admin Fri, 08 Jan 2010 04:29:00 GMT

So Rails Templates have been around now since 2.3.0.  I have finally found the time to dig in and enjoy them, after watching Ryan Bates’ screencast episode 148.

Feel free to use my base_template or any of my rails generators which can be found at github.com/cblackburn.  My template is pretty basic, but I’ve wanted a way to do this kind of thing for years.  I used to write shell scripts to setup my default Rails applications. This is so much nicer!

To use it just do this:

rails appname -m http://github.com/cblackburn/rails-templates/raw/master/base_template.rb

  # Plugins
  plugin 'exception_notifier', :git => 'git://github.com/rails/exception_notification.git'

  # Gems
  if yes?("Will you need to paginate?")
    gem "mislav-will_paginate", :lib => 'will_paginate'
  end
  rake("gems:install", :sudo => true)

  # Generators
  generate :app_layout
  if yes?("Will you be using MySQL?")
    db_password = ask("What is the MySQL password for root?")
    puts "Type 'y' and Enter to overwrite the current database.yml file."
    generate( "database_yml_mysql #{db_password}") # This uses my own generator
  end
  if yes?("Do you need Authlogic?")
    generate :authlogic # This uses my authlogic-generator
  end
  generate :controller, "home index"
  route "map.root :controller => :home"

  # General cleanup
  rake "db:create:all"
  rake "db:migrate"
  run "echo TODO > README"
  run "rm -f public/index.html"

  # Files
  file ".gitignore", <<-END
  .DS_Store
  log/*.log
  log/*.pid
  tmp/**/*
  config/database.yml
  db/*.sqlite3
  END

  # Git
  git :init
  git :add => "."
  git :commit => "-m 'initial commit'"

If you decide to use this you’ll also want to take a look at my generators: http://github.com/cblackburn/personal-rails-generators

RoR Sorting Collection of Hashes

Posted by admin Fri, 06 Oct 2006 05:00:00 GMT

I have found myself needing to sort a hash collection often, by a value within the hashes. The last instance where I needed this was to sort an aggregated result set of multiple union queries. So sorting with an order by clause would not work across the unions.

The solution is below. I pass a sort_clause into the method that would look like this company_name asc or company_name desc.

def stats(sort_clause)

    # queries, etc.
    ...

    find_by_sql(sql).each do |acct|
      aid = acct.id.to_i
      results[aid] = {} unless results[aid]
      month = acct.monthname
      case (month)
        when 'last'
          results[aid][:spend_last] = acct.spend.to_f
        when 'this'
          results[aid][:spend_this] = acct.spend.to_f
        when 'total'
          results[aid][:company_name] = acct.company_name
          results[aid][:balance]      = acct.bal.to_f
          results[aid][:campaigns]    = acct.campaign_count.to_i
          results[aid][:keywords]     = acct.keyword_count.to_i
      end
    end

    sort_col, order = sort_clause.split(' ')
    logger.debug("sort_clause: #{sort_clause}")
    results = results.sort_by{ |item|
      item[1][sort_col.intern]
    }
    if (order =~ /desc/i)
      results.reverse!
    end
    results
end

Acts As Bytefield :: ActiveRecord Bytefield Plugin

Posted by admin Mon, 23 Apr 2007 05:00:00 GMT

We needed a convenient way to store a series of values in a single field. A bitfield would not do because it would only allow a value of 1 or 0 for each field, and we wanted to be able to store at least 3 values for each field.

So I found Gabriel Gironda’s acts_as_bitfield plugin and made a few tweaks. ActsAsBytefield is the result. It allows storage of 256 values in each field, or 255 discrete values ranging from 0-255 (unsigned char or byte) for each value in a MySQL varchar(255) field.

NOTE: Gabriel’s site has been down for some time. My own repository has also been down but is now back up. Sorry for the inconvenience.

Values greater than 255, or less than 0 wrap around. For example, setting a bytefield column to -1 will actually set it to 255, and setting it to -2 will actually set it to 254, etc.

Installation

./script/plugin install acts_as_bytefield

OR
./script/plugin install https://svn.cbciweb.com/svn/plugins/acts_as_bytefield

Documentation (RDoc)

rake rdoc

Testing

The tests require rspec

rake test

Usage

  • Create a string column in your table - varchar(255)
  • Add this directive to your model:
 acts_as_bytefield :bytefield_column_name, :fields => [:field_name_one, :field_name_two]

You will then be able to use the model in the following manner, for example:

 class SomeModel < ActiveRecord::Base
   acts_as_bytefield :bfield, :fields => [:test, :production]
 end

 obj = SomeModel.new(:test => 1)

 obj.test          #=> 1
 obj.test?         #=> 1
 obj.production?   #=> 0

 obj.test = 0
 obj.production = 65
 obj.save

 obj.test?         #=> 0
 obj.production?   #=> 65

 # The field that's storing the value:
 obj.bfield        #=> "\000A"