simple_accessible_filter.rb

# Sneaky attr_accessible clone for MongoMapper

class Filter  
  def initialize(hash)
    @hash = hash
  end
  
  def accessible(*values)
    @accessible = []
    values.each {|value| @accessible<< value }
  end
  
  def filter
    @hash.each_pair{|key, value| @accessible.include?(key.to_sym) ? next : @hash.delete(key)}
  end
end

# Some test hash
some_param = {:title => "Some title", :content => "Some content", :author => "Some author" }

a = Filter.new(some_param)

# This line is similar to attr_accessible. Need to type here array of keys
a.accessible :title

# This will puts our filtered "some_param" hash
a.filter.each_pair {|key, value| puts "#{key}:#{value}"} # => title:Some title