openproject/app/models/token.rb

class Token < ActiveRecord::Base
  belongs_to :user
  validates_uniqueness_of :value
  
  before_create :delete_previous_tokens
  
  @@validity_time = 1.day
  
  def before_create
    self.value = Token.generate_token_value
  end

  # Return true if token has expired  
  def expired?
    return Time.now > self.created_on + @@validity_time
  end
  
  # Delete all expired tokens
  def self.destroy_expired
    Token.delete_all ["action <> 'feeds' AND created_on < ?", Time.now - @@validity_time]
  end
  
private
  def self.generate_token_value
    ActiveSupport::SecureRandom.hex(20)
  end
  
  # Removes obsolete tokens (same user and action)
  def delete_previous_tokens
    if user
      Token.delete_all(['user_id = ? AND action = ?', user.id, action])
    end
  end
end