Session data available in controller, but not model?

[Eric.Coleman]

Ok, thanks to everyone who's helped me out so far... so close to being done with the boring parts

I have documents that upload, and I need to associate a id that's in a session to the document. What I have in my model is:

class Document < ActiveRecord::Base
  ..

  def before_save
    self.project_id = session[:project_id]
    ..
  end
..

Basically, it's saying it's not available (undefined local variable or method `session' for #<Object:0x2799258>)

However, it's available in the controller. Is there something I should be doing to get it there? Maybe im just not sure why session is local to the controller and not the model...

[vgarcia]

Have you tried using @session instead of session?

[Eric.Coleman]

Vinnie,

It doesnt, I get:

ou have a nil object when you didn't expect it!
You might have expected an instance of Array.
The error occured while evaluating nil.[]

Thanks for your help

[sweatje]

I am certainly not a Rails or Ruby expert, but since you are probably accessing the model either in the context of a method of the controller, or in a view eventually routed to from the controller, couldn't you just have the controller pass the session into a model which needed access to it?

[Eric.Coleman]

Jason, I am actually not sure. I know that a method called "before_save" in the model will be called before your data is saved, so I have this to deal with a file upload, and the project id

def before_save
    # set the project id
    self.project_id = @session[:project_id]

    # handle the file upload
    file_name = Time.now.to_i
    
    file = self.file_name.rewind

    File.open("in_docs/#{file_name}", 'wb') { |f| f.write(file.read) }

    self.file_name      = file.original_filename
    self.file_real_name = file_name
    self.content_type   = file.content_type
  end

[sweatje]

Maybe just remove the session dependancy from the Model entirely?

# in the controller
  def file_upload
    file = new ModelThing
    file.project_id = session[:project_id]
    file.save
  end

So that all of the session manipulation is external to the Model code?

[Luke Redpath]

The session isn't available in the model because it shouldn't be, to maintain the separation of business and application logic that MVC provides. You should pass any values needed by your model into it as a method parameter (or possibly in the constructor depending on where you need that value), regardless of where that value comes from.

EDIT - or do what Jason suggested.

[MiiJaySung]

Ditto to what Luke says. Again though I have found that occasionally that I get annoyed because I can not do everything in the model I want to do, but there is a good reason for it.

If you need access to things like sessions, params and url manuipulation etc in your model, there it saying there's smething wrong about your design.