Use ActiveRecord to generate Random Data on a Table

argen.rb

require "active_record"
require "ffaker"
  
class Post < ActiveRecord::Base
end

class Generator
  
  SQL_TYPE_TO_DATA_MAPPING = {
    :varchar => /^varchar\((\d+)\)/,
    :text => /^text/
  }
  
  # Establish Database connection
  def initialize conf_file
    config = YAML::load File.open conf_file
    ActiveRecord::Base.establish_connection config
  end
  
  def generate
    # Generate the data table for a Post like { fieldname => sqltype }
    column_data = Post.columns_hash.inject({}) do |hash, (key, value)|  
      hash[key] = value.sql_type
      hash
    end
    Post.create! build_data column_data
  end
  
  private 
    def build_data column_data
      column_data.inject({}) do |hash, (field,type)|
        Generator::SQL_TYPE_TO_DATA_MAPPING.map do |func,matcher|
          if (m = matcher.match type)
            if [:varchar].include? func
              hash[field] = send func, *m[1]
            elsif [:text].include? func
              hash[field] = send func, *m[1..2]
            else
              p m
            end
            break
          end
        end
        hash
      end
    end
        
    # Generate random chars with length
    def varchar chars
      Faker::Lorem.words(30).join[0..chars.to_i]
    end
    
    # Generate a Random text
    def text
      Faker::Lorem.paragraph
    end
end

# Connect the Database
generator = Generator.new "database.yml"
# Genearte 100 Records
100.times { generator.generate }