extract_fixtures.rake

namespace :db do
  namespace :fixtures do
    
desc ' Creates YAML test fixtures from data in an existing database.
Parameters:
RAILS_ENV - use to select databese. Default is to development database (eg. RAILS_ENV=test).
TABLES - use to select tables to extract. By default all tables are extractd. (eg. TABLES=users,orders).
DIR - use to change default (/test/fixtures) write directory (eg. DIR=./db/data).'
task :extract => :environment do
  dir = ENV['DIR'] || "#{RAILS_ROOT}/test/fixtures"
  sql  = "SELECT * FROM %s ORDER BY id ASC"
  ActiveRecord::Base.establish_connection

  if ENV['TABLES']
    interesting_tables = ENV['TABLES'].split(',')
  else
    skip_tables = ['schema_info', 'schema_migrations', 'sessions', 'logged_exceptions',
      'plugin_schema_info', 'order_types_orders']
    interesting_tables = (ActiveRecord::Base.connection.tables - skip_tables)
  end
  
  interesting_tables.each do |table_name|
    i = "000"
    File.open("#{dir}/#{table_name}.yml", 'w' ) do |file|
      data = ActiveRecord::Base.connection.select_all(sql % table_name)
      puts "Writing #{table_name}.yml..."
      file.write data.inject({}) { |hash, record|
        hash["#{table_name}_#{i.succ!}"] = record
        hash
      }.to_yaml
    end
  end
end

desc ' Loads data from selected fixtures to a database.
Parameters:
RAILS_ENV - use to select databese. Default is to development database (eg. RAILS_ENV=test).
FIXTURES - use to select fixtures to load in (e.g. FIXTURES=users,orders).
DIR - use to change default (/test/fixtures) write directory (eg. DIR=./db/data).'
task :load_in => [:environment] do

  interesting_tables = ENV['FIXTURES'].split(',')
  dir = ENV['DIR'] || "#{RAILS_ROOT}/test/fixtures"
  FileUtils.mkdir_p(dir)
  FileUtils.chdir(dir)

  interesting_tables.each do |table_name|
    ActiveRecord::Base.transaction do
      puts "Clearing #{table_name}..."
      ActiveRecord::Base.connection.execute "DELETE FROM #{table_name}", "Table Clearance"
      puts "Loading #{table_name}..."
      YAML.load_file("#{table_name}.yml").each do |fixture|
        fixture = fixture[1]
        ActiveRecord::Base.connection.execute "INSERT INTO #{table_name} (#{fixture.keys.join(",")}) VALUES (#{fixture.values.collect { |value| ActiveRecord::Base.connection.quote(value) }.join(",")})", 'Fixture Insert'
      end
    end
  end
end

  end
end