db_store.rb

require 'openid/store/interface'

module OpenID::Store
  class Association 
    include Mongoid::Document
    field :secret, :type => Binary

    def from_record
      OpenID::Association.new(handle, secret.to_s, issued, lifetime, assoc_type)
    end
  end

  class Nonce
    include Mongoid::Document
  end

  class DbStore < OpenID::Store::Interface
    def self.cleanup_nonces
      now = Time.now.to_i
      Nonce.delete_all(["timestamp > ? OR timestamp < ?", now + OpenID::Nonce.skew, now - OpenID::Nonce.skew])
    end

    def self.cleanup_associations
      now = Time.now.to_i
      Association.delete_all(['issued + lifetime > ?',now])
    end

    def store_association(server_url, assoc)
      remove_association(server_url, assoc.handle)

      # BSON::Binary is used because secrets raise an exception
      # due to character encoding
      Association.create(:server_url => server_url,
                         :handle     => assoc.handle,
                         :secret     => BSON::Binary.new(assoc.secret),
                         :issued     => assoc.issued,
                         :lifetime   => assoc.lifetime,
                         :assoc_type => assoc.assoc_type)
    end

    def get_association(server_url, handle = nil)
      assocs = if handle.blank?
        Association.find :all, :conditions => { :server_url => server_url }
      else
        Association.find :all, :conditions => { :server_url => server_url, :handle => handle }
      end

      assocs.reverse.each do |assoc|
        a = assoc.from_record
        if a.expires_in == 0
          assoc.destroy
        else
          return a
        end
      end if assocs.any?

      return nil
    end

    def remove_association(server_url, handle)
      Association.find(:all, :conditions => { :server_url => server_url, :handle => handle }).each do |assoc|
        assoc.destroy!
      end
    end

    def use_nonce(server_url, timestamp, salt)
      return false if Nonce.find(:first, :conditions => { :server_url => server_url, :timestamp => timestamp, :salt => salt})
      return false if (timestamp - Time.now.to_i).abs > OpenID::Nonce.skew
      Nonce.create(:server_url => server_url, :timestamp => timestamp, :salt => salt)
      return true
    end
  end
end