Rails Script

Sometimes I want to write a ruby script that uses the models or other things in the Rails application. The simplest way to do it is to write a little script and executes it with Rails script runner. But what if the script is more than a few lines of code and needs to be able to handle multiple arguments? Let’s say I want to build a thrift server that uses Rails models and put it under Rails.root/script folder:

#!/usr/bin/env ruby
require 'optparse'

# Default options
app_config = { :environment => "development" }

# Parses options
OptionParser.new do |opts|
  opts.on("-e", "--environment=name", String,
          "Specifies the environment for the server to operate under (test/development/production).",
          "Default: development") { |v| app_config[:environment] = v }
  opts.on("-p", "--port=name", Integer,
          "Runs thrift server on the specific port.",
          "Default: 9090") { |v| app_config[:port] = v }
end.parse!

ENV["RAILS_ENV"] ||= app_config[:environment]

STDOUT.sync = true

# Loads Rails environment
require File.expand_path('../../config/boot',  __FILE__)
require File.expand_path("../../config/environment", __FILE__)

app_config = YAML::load(ERB.new(IO.read(File.join(Rails.root,
  'config/app.yml'))).result)[Rails.env].with_indifferent_access.merge(app_config)

port = app_config[:port] || 9090
thread_count = app_config[:thread] || 1

# Includes thrift-generated code
$:.push("#{Rails.root}/app/thrift")

class AppServiceHandler
  
  def initialize(options = {})
    ...
  end
  
  ...

end

handler = AppServiceHandler.new(app_config)
processor = AppService::Processor.new(handler)
transport = Thrift::ServerSocket.new(port)
transportFactory = Thrift::BufferedTransportFactory.new()
protocolFactory = Thrift::BinaryProtocolFactory.new()
server = Thrift::ThreadPoolServer.new(processor, transport, transportFactory, protocolFactory, thread_count)
server.serve()