diff .svn/pristine/2f/2fb2c04645c15a567f773c73750f1da4ba45dfba.svn-base @ 926:b73a59a6acbd luisf

Merge from cannam_integration

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/.svn/pristine/2f/2fb2c04645c15a567f773c73750f1da4ba45dfba.svn-base	Fri May 11 16:10:11 2012 +0100
@@ -0,0 +1,73 @@
+require 'digest/sha1'
+require 'openid/store/interface'
+
+module OpenIdAuthentication
+  class MemCacheStore < OpenID::Store::Interface
+    def initialize(*addresses)
+      @connection = ActiveSupport::Cache::MemCacheStore.new(addresses)
+    end
+
+    def store_association(server_url, assoc)
+      server_key = association_server_key(server_url)
+      assoc_key = association_key(server_url, assoc.handle)
+
+      assocs = @connection.read(server_key) || {}
+      assocs[assoc.issued] = assoc_key
+
+      @connection.write(server_key, assocs)
+      @connection.write(assoc_key, assoc, :expires_in => assoc.lifetime)
+    end
+
+    def get_association(server_url, handle = nil)
+      if handle
+        @connection.read(association_key(server_url, handle))
+      else
+        server_key = association_server_key(server_url)
+        assocs = @connection.read(server_key)
+        return if assocs.nil?
+
+        last_key = assocs[assocs.keys.sort.last]
+        @connection.read(last_key)
+      end
+    end
+
+    def remove_association(server_url, handle)
+      server_key = association_server_key(server_url)
+      assoc_key = association_key(server_url, handle)
+      assocs = @connection.read(server_key)
+
+      return false unless assocs && assocs.has_value?(assoc_key)
+
+      assocs = assocs.delete_if { |key, value| value == assoc_key }
+
+      @connection.write(server_key, assocs)
+      @connection.delete(assoc_key)
+
+      return true
+    end
+
+    def use_nonce(server_url, timestamp, salt)
+      return false if @connection.read(nonce_key(server_url, salt))
+      return false if (timestamp - Time.now.to_i).abs > OpenID::Nonce.skew
+      @connection.write(nonce_key(server_url, salt), timestamp, :expires_in => OpenID::Nonce.skew)
+      return true
+    end
+
+    private
+      def association_key(server_url, handle = nil)
+        "openid_association_#{digest(server_url)}_#{digest(handle)}"
+      end
+
+      def association_server_key(server_url)
+        "openid_association_server_#{digest(server_url)}"
+      end
+
+      def nonce_key(server_url, salt)
+        "openid_nonce_#{digest(server_url)}_#{digest(salt)}"
+      end
+
+      def digest(text)
+        Digest::SHA1.hexdigest(text)
+      end
+  end
+end