import seed data from .csv or .yml for Rails 2.3.4+

README.md

Rails SeedImporter

1. Put this code at #{Rails.root}/db/seeds.rb
2. type rake db:setup

Limitation

It supports only `id' primary key.

seeds.rb

# -*- mode: ruby; coding: utf-8 -*-
class SeedImporter
  def initialize
    @model            = nil
    @with_id          = false
    @dragonfly_fields = []
    @paperclip_fields = []
  end

  def run
    Dir.glob( File.join( seed_dir, '**/*.{yml,csv}' ) ).sort.each { |seed|
      send( "import_#{File.extname( seed )[1..-1]}_seed", seed )
    }
  end

  def seed_dir
    ENV['SEED_DIR'] || File.dirname(__FILE__) + '/seeds'
  end

  def fcsv_opts
    { :headers           => true,
      :header_converters => :downcase }
  end

  def import_csv_seed( file )
    init_model( file, '.csv' )
    FasterCSV.table( file, fcsv_opts ) { |csv|
      @with_id = csv.headers.include?( 'id' )
    }
    if ( @with_id )
      _import_csv( file ) { |row| create_and_save_with_id( row.to_hash ) }
    else
      _import_csv( file ) { |row| create_and_save( row.to_hash ) }
    end
  end

  def _import_csv( file, &block )
    FasterCSV.open( file, fcsv_opts ).each { |csv| block.call( csv ) }
  end

  def import_yml_seed( file )
    init_model( file, '.yml' )
    YAML.load_file( file ).each_pair { |k, v|
      if ( v.has_key?( 'id' ) )
        create_and_save_with_id( v )
      else
        create_and_save( v )
      end
    }
  end

  def to_model( file, suffix )
    File.basename( file, suffix ).sub( /\A[0-9]+(_\.)?/, '' ).classify
  end

  def init_model( file, suffix )
    @model = Object.const_get( to_model( file, suffix ) )
    init_file_fields
  end

  def create_and_save( data )
    save( create( data ) )
  end

  def create_and_save_with_id( data )
    record       = create( data )
    record['id'] = data['id']
    save( record )
  end

  def create( data )
    attach_file_when_need( data )
  end

  def attach_file_when_need( data )
    record = @model.new( data )

    if ( @dragonfly_fields.size > 0 )
      @dragonfly_fields.each { |e|
        col  = e.to_s
        file = data[e] || data[e.to_s]
        path = File.join( seed_dir, file )
        record.send( "#{col}=",
                     open( path ).read ) if file and File.exist?( path )
      }
    end
    if ( @paperclip_fields.size > 0 )
      @paperclip_fields.each { |e|
        col  = e.to_s
        file = data[e] || data[e.to_s]
        path = File.join( seed_dir, file )
        record.send( "#{col}=",
                     open( path ) ) if file and File.exist?( path )
      }
    end

    record
  end

  def save( record )
    begin
      record.save!
    rescue => e
      p record
      p record.errors
      raise e
    end
  end

  def init_file_fields
    if ( defined? ::Dragonfly )
      @dragonfly_fields =
        if @model.respond_to? :dragonfly_apps_for_attributes # v0.8
          @model.dragonfly_apps_for_attributes.keys
        elsif @model.respond_to? :dragonfly_attachment_classes # v0.9
          @model.dragonfly_attachment_classes.map { |c|
            c.attribute
          }
        end
    end
    if ( defined? ::Paperclip )
      @paperclip_fields = @model.attachment_definitions.keys if @model.attachment_definitions
    end
  end
end

SeedImporter.new.run

You can use fast_seeder(https://github.com/greyblake/fast_seeder) as well. It support number of DB adapters.