Plugin: include vs. base.send :include

rubyonrails-talk
1

Hello all,

I've created a simple plugin to extend the functionality of my controllers. So in my plugins/<plugin>/lib directory I created the following module:

module MyPlugin   def self.included(base)     include InstanceMethods   end

  module InstanceMethods     def some_method       ..     end   end end

To extend the controllers just put

  include MyPlugin

somewhere in ApplicationController and that's it... I thought! I found out that 'include InstanceMethods' will only work if my application is running in 'development'. When running in 'production' calling 'some_method' will result in a ActionController::UnknownAction exception.

If I change the 'include' line into:   base.send(:include, InstanceMethods) things will work fine, so after all there's no problem at all, but I'm just curious of someone of has the same experience and if there's a difference between 'include' and 'base.send :include'?

Thanks in advance.

(I'm using Rails 1.2.6).

2

To extend the controllers just put

include MyPlugin

somewhere in ApplicationController and that's it... I thought! I found out that 'include InstanceMethods' will only work if my application is running in 'development'. When running in 'production' calling 'some_method' will result in a ActionController::UnknownAction exception.

If I change the 'include' line into: base.send(:include, InstanceMethods) things will work fine, so after all there's no problem at all, but I'm just curious of someone of has the same experience and if there's a difference between 'include' and 'base.send :include'?

Well it's all about who's doing the include, in one case you're doing
it to MyPlugin (after the module has been included in
ApplicationController), in the other case you're doing it to
ApplicationController itself (since that's what Base will be). I
suspect you're just been lucky: in development mode you keep getting
reloaded, so the first time round the methods aren't added to
ApplicationController, but they are added to MyPlugin, and the second
and following times since they are in MyPlugin they are also added to
ApplicationController. When class caching is on (ie in production)
things are only loaded once and so the methods aren't added to the
controllers. (not sure if you're doing this on purpose, but do you
know that what you've got there is equivalent to

module MyPlugin    def some_method    end end )

3

Hi Frederick,

Thanks so much for your response. It made it all so much clearer, and, I must admit, now reading your explanation, I've had to figure it out myself...

There is no reason for using 'base.send :include' instead of just including the module. To be honest, I changed my code to your suggestion.

Patrick