Question

I’m trying to do the following in my Rails 3 model:

require 'securerandom'

class Contest < ActiveRecord::Base
  attr_accessor :key
  before_create :generate_key

  private

  def generate_key
    self.key = SecureRandom.hex(3)
  end

end

However when I create a Contest, all the fields in my table appear to be correct except the key which remains nil in my DB.

More Info:

In my rails server log, I see the following when I create a contest through my “create contest form”

SQL (0.5ms)  INSERT INTO "contests" ("category", "created_at", "description", "key", "price", "status", "time", "title", "updated_at", "user_id") VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?)  [["category", "camisas"], ["created_at", Wed, 15 Feb 2012 18:57:16 UTC +00:00], ["description", "test_description"], ["key", nil], ["price", 111], ["status", "In process"], ["time", "2sem"], ["title", "test_contest"], ["updated_at", Wed, 15 Feb 2012 18:57:16 UTC +00:00], ["user_id", 5]]

Note the [“key”, nil]

But that should be correct right?, I would guess that the key will be added by the Contest.rb :before_create callback?

Maybe I’m miss-using SecureRandom?

Answer 1

Why are you using attr_accessor? This method is actually going to be defining both a setter and getter method for a key, keeping track of a virtual attribute.

Perhaps you meant to use attr_accessible, but even then that is unnecessary, because you’re setting the attribute directly.

Really, you don’t need either attr_accessor :key or attr_accessible :key in your model at all if you’re just setting it like this. Remove the attr_accessor and it will work.