Rails: difference between attr_accessor and attr_accessible

Question

What is the difference? Also, why does this not work:

The variables such as base_path are not being set.

class Cvit < ActiveRecord::Base
  attr_accessible :species,:program,:textup,:e_value,:filter,:min_identity,:cluster_dist,:fileup_file_name
  attr_accessor :base_path, :fa_file, :text_file, :dbase, :source, :bl_file, :bl_sorted, :gff_file, :cvt_file, :db, :overlay_coords_gray

  def initilize(*args)
     super(*args)
  end

  def cvitSetup()
    self.base_path = "blast_cvit/"
    self.fa_file = "input.fa"
    .
    .
  end
end

in the rails console the attributes get set correctly however when I try to do this:

controller:

def show
    @cvit = Cvit.find(params[:id])
    @cvit.cvitSetup()
    @cvit.blast()
    @cvit.generateGff()
    @cvit.generateCvitImage()


    respond_to do |format|
      format.html # show.html.erb
      format.xml  { render :xml => @cvit }
    end
  end

and in my view I reference @cvit.some_attribute.html_safe but that attribute is null so I get an error. Any ideas?

score 8 · Accepted Answer · edited Aug 05 '11 at 16:15

attr_accessor creates the getter method.attribute and setter method.attribute= for the specified attributes.

attr_accessible is from ActiveRecord::Base and "Specifies a white list of model attributes that can be set via mass-assignment." See documentation and example here.

EDIT:

As for your second question, I don't know. I tried this dummy code and it worked:

class Test
attr_accessor :base_path, :fa_file
  def cvitSetup()
    self.base_path = "blast_cvit/"
    self.fa_file = "input.fa"
  end
end
t = Test.new
t.cvitSetup
p t.base_path
#=> "blast_cvit/"

Are you sure that you properly instantiated your class?

score 1 · Answer 2 · answered Aug 05 '11 at 17:23

attr_accessor simply creates a getter-setter method for an attribute.

attr_accessible specifies a white list of model attributes that can be set via mass-assignment, such as new(attributes), update_attributes(attributes), or attributes=(attributes). This has been excerpted from the link here

Rails: difference between attr_accessor and attr_accessible

2 Answers2

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