# HG changeset patch
# User Thierry Florac <tflorac@ulthar.net>
# Date 1351184232 -7200
# Node ID 28ecb13e485ccbfff28a9a2646dfa048d63d5c06
# Parent  1715bc6df5628a599d51936924ddddd2fe762700
Added request and session cached properties

diff -r 1715bc6df562 -r 28ecb13e485c src/ztfy/utils/property.py
--- a/src/ztfy/utils/property.py	Thu Oct 25 11:39:05 2012 +0200
+++ b/src/ztfy/utils/property.py	Thu Oct 25 18:57:12 2012 +0200
@@ -23,6 +23,8 @@
 # import Zope3 packages
 
 # import local packages
+from ztfy.utils.request import queryRequest, getRequestData, setRequestData
+from ztfy.utils.session import getSessionData, setSessionData
 
 
 class cached(object):
@@ -63,3 +65,46 @@
             return self
         obj.__dict__[self.__name__] = result = self.fget(obj)
         return result
+
+
+_marker = object()
+
+class request_property(object):
+    """Define a request cached property"""
+
+    def __init__(self, fget, key=None):
+        self.fget = fget
+        if key is None:
+            key = "%s.%s" % (fget.__module__, fget.__name__)
+        self.key = key
+
+    def __get__(self, obj, cls):
+        if obj is None:
+            return self
+        request = queryRequest()
+        data = getRequestData(self.key, request, _marker)
+        if data is _marker:
+            data = self.fget(obj)
+            setRequestData(self.key, data, request)
+        return data
+
+
+class session_property(object):
+    """Define a property for which computed value is stored into session"""
+
+    def __init__(self, fget, app, key=None):
+        self.fget = fget
+        self.app = app
+        if key is None:
+            key = "%s.%s" % (fget.__module__, fget.__name__)
+        self.key = key
+
+    def __get__(self, obj, cls):
+        if obj is None:
+            return self
+        request = queryRequest()
+        data = getSessionData(request, self.app, self.key, _marker)
+        if data is _marker:
+            data = self.fget(obj)
+            setSessionData(request, self.app, self.key, data)
+        return data
diff -r 1715bc6df562 -r 28ecb13e485c src/ztfy/utils/session.py
--- a/src/ztfy/utils/session.py	Thu Oct 25 11:39:05 2012 +0200
+++ b/src/ztfy/utils/session.py	Thu Oct 25 18:57:12 2012 +0200
@@ -33,8 +33,12 @@
     session = ISession(request)[app]
     return session.get(key, default)
 
+getSessionData = getData
+
 
 def setData(request, app, key, value):
     """Set data associated to a given session"""
     session = ISession(request)[app]
     session[key] = unproxied(value)
+
+setSessionData = setData