import_user.rb

# legacy User class to import users from a vbulletion database
class LegacyUser < LegacyModel
  # important! please change:
  self.model = User # which is the new Rails model
  self.table_name = "vbulletin_user" # the vbulletin table name
  
  # attribue mapping: {:rails => :vbulletin}
  self.attribute_mapping = {:legacy_id => :userid, :name => :username, :email => :email, :password => :email, :password_confirmation => :email} # map old vbulletin attrbute names to new rails attribute names  {:rails => :vbulletin}
  
  attr_accessor *self.attribute_mapping.values
  #attr :attribute # any other important attributes?
  # change this only if needed
  self.database = "vbulletin_"
  self.username = "root"
  self.password = ""
  self.host     = "localhost"
  
   
  def after_save(imported_object)
    imported_object.register!
    imported_object.activate!
  end
end

legacy_model.rb

# Idea of an Legacy Database Importer
# I've used this to import data from a vbulletin board to a Rails app
# This is a LeagacyModel class which handles your DB connection and the importin
# have a look at the ImportUser class for an usage example and some "documentation"
#
require "active_support"
require "logger"
require "mysql"
require "active_record"
MysqlCompat.define_all_hashes_method!

class LegacyModel
  cattr_accessor :model, :attribute_mapping, :errors, :table_name, :database, :host, :username,:password, :logger
  
  
  def initialize(attributes={})
    attributes.each do |key,value|
      self.send("#{key}=",value) if self.respond_to?("#{key}=")
    end
  end
  def import
    import_object = self.class.model.new
    attribute_mapping.each do |key,value|
      import_object.send("#{key}=",self.send(value))
    end
    import_object.save
    
    if !import_object.new_record?
      after_save(import_object)
    else
      self.class.error(import_object)
    end
    
  end
  
  def after_save(import_object)
    
  end
  
  def self.import_all
    self.all.each do |o|
      o.import
    end
  end
  
  def self.all
    returning [] do |collection|
      connection.select_all("select * from #{self.table_name}").each do |entry|
        collection << self.new(entry)
      end
    end
  end
  
  def self.error(object)
    @@errors ||= []
    @@errors << object
  end
  
  def self.map_errors_to(attribute)
    @@errors.collect {|e| { e.send(attribute) => e.errors } }
  end
  def self.map_formatted_errors_to(attribute)
    @@errors.collect {|e| { e.send(attribute) => e.errors.full_messages } }
  end
  
  def self.connection
    @@connection ||= ActiveRecord::ConnectionAdapters::MysqlAdapter.new(Mysql.init, self.logger, [self.host, self.username, self.password, self.database, nil, nil], {:host => self.host, :user => self.username, :password=>self.password, :encoding=>"utf8"})
  end
  def self.logger
    @@logger ||= (Rails.logger || Logger.new(STDOUT))
  end
end