Question

I’m working on a Rails app and am looking to include some functionality from ‘Getting the Hostname or IP in Ruby on Rails‘ that I asked.

I’m having problems getting it to work. I was under the impression that I should just make a file in the lib directory, so I named it ‘get_ip.rb’, with the contents:

require 'socket'  module GetIP   def local_ip     orig, Socket.do_not_reverse_lookup = Socket.do_not_reverse_lookup, true  # turn off reverse DNS resolution temporarily      UDPSocket.open do |s|       s.connect '64.233.187.99', 1       s.addr.last     end   ensure     Socket.do_not_reverse_lookup = orig   end end 

I had also tried defining GetIP as a class but when I do the usual ruby script/console, I’m not able to use the local_ip method at all. Any ideas?

Answer 1

You haven’t described how you’re trying to use the method, so I apologize in advance if this is stuff you already know.

The methods on a module never come into use unless the module is included into a class. Instance methods on a class require there to be an instance of the class. You probably want a class method instead. And the file itself should be loaded, generally through the require statement.

If the following code is in the file getip.rb,

require 'socket'  class GetIP   def self.local_ip     orig, Socket.do_not_reverse_lookup = Socket.do_not_reverse_lookup, true      UDPSocket.open do |s|       s.connect '64.233.187.99', 1       s.addr.last     end   ensure     Socket.do_not_reverse_lookup = orig   end end 

Then you should be able to run it by saying,

require 'getip' GetIP.local_ip