Question

I followed this tutorial to create a simple command-line gem and now I want to extend functionality with raad. Currently I have made the following changes after following the tutorial:

bin/zerp:

#!/usr/bin/env ruby

require 'zerp'

class Zerp    
  def start
    Raad::Logger.debug 'zerp started'

    EventMachine.run do
      EventMachine.add_periodic_timer(1) do
        Raad::Logger.info 'zerp is running'
      end
    end
  end

  def stop
    EventMachine.stop
    Raad::Logger.debug 'zerp stopped'
  end
end

lib/zerp.rb:

require 'zerp/version'

require 'eventmachine'
require 'raad'

module Zerp
end

When I run the client from commandline I get the following error.

user@zenbook:~/git/zerp :) zerp
/home/user/.local/lib/ry/rubies/1.9.3-p194/lib/ruby/gems/1.9.1/gems/zerp-0.0.1/bin/zerp:5:in `<top (required)>': Zerp is not a class (TypeError)
    from /home/user/.local/lib/ry/current/bin/zerp:23:in `load'
    from /home/user/.local/lib/ry/current/bin/zerp:23:in `<main>'
user@zenbook:~/git/zerp :( 

What is the proper approach to get this working?

Answer 1

This is a use-case I did not really look into when making Raad and only minor modifications will make it better integrate within a “executable” gem context. In the meantime you can use this workaround:

bin/zerp

#!/usr/bin/env ruby

begin
  require 'zerp'
rescue LoadError
  $:.unshift 'zerp/lib'
  require 'zerp'
end

# raad must be required after the Zerp class definition
require 'raad'

zerp/lib/zerp.rb

require "zerp/version"
require "zerp/service"

zerp/lib/service.rb

require 'eventmachine'

class Zerp    
  def start
    Raad::Logger.debug 'zerp started'

    EventMachine.run do
      EventMachine.add_periodic_timer(1) do
        Raad::Logger.info 'zerp is running'
      end
    end
  end

  def stop
    EventMachine.stop
    Raad::Logger.debug 'zerp stopped'
  end
end

zerp/lib/version

module ZerpModule
  VERSION = "0.0.1"
end

The way Raad works right now is that since the file requiring the raad gem is “zerp” then Raad tries to bootstrap using the “Zerp” class. To avoid conflicts you should use another module name than “Zerp” – I just picked “ZerpModule”.

I’ll try to make a fix shortly to have Raad integrate better in a gem context.