Merge branch 'master' of ssh://git.labs.libre-entreprise.org/gitroot/tiramisu
[tiramisu.git] / tiramisu / setting.py
index 3c649fe..86f900e 100644 (file)
@@ -22,7 +22,9 @@
 # ____________________________________________________________
 from time import time
 from copy import copy
-from tiramisu.error import RequirementError, PropertiesOptionError
+import weakref
+from tiramisu.error import (RequirementError, PropertiesOptionError,
+                            ConstError, ConfigError)
 from tiramisu.i18n import _
 
 
@@ -34,28 +36,45 @@ ro_append = ('frozen', 'disabled', 'validator', 'everything_frozen',
 rw_remove = ('permissive', 'everything_frozen', 'mandatory')
 rw_append = ('frozen', 'disabled', 'validator', 'hidden')
 default_properties = ('expire', 'validator')
-storage_type = 'dictionary'
 
 
-class _const:
+class StorageType:
+    default_storage = 'dictionary'
+    storage_type = None
+
+    def set_storage(self, name):
+        if self.storage_type is not None:
+            raise ConfigError(_('storage_type is already set, cannot rebind it'))
+        self.storage_type = name
+
+    def get_storage(self):
+        if self.storage_type is None:
+            self.storage_type = self.default_storage
+        storage = self.storage_type
+        return 'tiramisu.storage.{0}.storage'.format(
+            storage)
+
+
+storage_type = StorageType()
+
+
+class _NameSpace:
     """convenient class that emulates a module
     and builds constants (that is, unique names)"""
-    class ConstError(TypeError):
-        pass
 
     def __setattr__(self, name, value):
         if name in self.__dict__:
-            raise self.ConstError, _("can't rebind group ({})").format(name)
+            raise ConstError(_("can't rebind {0}").format(name))
         self.__dict__[name] = value
 
     def __delattr__(self, name):
         if name in self.__dict__:
-            raise self.ConstError, _("can't unbind group ({})").format(name)
+            raise ConstError(_("can't unbind {0}").format(name))
         raise ValueError(name)
 
 
 # ____________________________________________________________
-class GroupModule(_const):
+class GroupModule(_NameSpace):
     "emulates a module to manage unique group (OptionDescription) names"
     class GroupType(str):
         """allowed normal group (OptionDescription) names
@@ -87,7 +106,7 @@ populate_groups()
 
 
 # ____________________________________________________________
-class OwnerModule(_const):
+class OwnerModule(_NameSpace):
     """emulates a module to manage unique owner names.
 
     owners are living in `Config._cfgimpl_value_owners`
@@ -113,18 +132,18 @@ def populate_owners():
     setattr(owners, 'default', owners.DefaultOwner('default'))
     setattr(owners, 'user', owners.Owner('user'))
 
-    def add_owner(name):
+    def addowner(name):
         """
         :param name: the name of the new owner
         """
         setattr(owners, name, owners.Owner(name))
-    setattr(owners, 'add_owner', add_owner)
+    setattr(owners, 'addowner', addowner)
 
 # names are in the module now
 populate_owners()
 
 
-class MultiTypeModule(_const):
+class MultiTypeModule(_NameSpace):
     "namespace for the master/slaves"
     class MultiType(str):
         pass
@@ -184,10 +203,43 @@ class Property(object):
         return str(list(self._properties))
 
 
+def set_storage(name, **args):
+    storage_type.set_storage(name)
+    settings = __import__(storage_type.get_storage(), globals(), locals(),
+                          ['Setting'], -1).Setting()
+    for option, value in args.items():
+        try:
+            getattr(settings, option)
+            setattr(settings, option, value)
+        except AttributeError:
+            raise ValueError(_('option {0} not already exists in storage {1}'
+                               '').format(option, name))
+
+
+def get_storage(context, session_id, persistent):
+    def gen_id(config):
+        return str(id(config)) + str(time())
+
+    if session_id is None:
+        session_id = gen_id(context)
+    return __import__(storage_type.get_storage(), globals(), locals(),
+                      ['Storage'], -1).Storage(session_id, persistent)
+
+
+def list_sessions():
+    return __import__(storage_type.get_storage(), globals(), locals(),
+                      ['list_sessions'], -1).list_sessions()
+
+
+def delete_session(session_id):
+    return __import__(storage_type.get_storage(), globals(), locals(),
+                      ['delete_session'], -1).delete_session(session_id)
+
+
 #____________________________________________________________
 class Settings(object):
     "``Config()``'s configuration options"
-    __slots__ = ('context', '_owner', '_p_')
+    __slots__ = ('context', '_owner', '_p_', '__weakref__')
 
     def __init__(self, context, storage):
         """
@@ -201,8 +253,8 @@ class Settings(object):
         """
         # generic owner
         self._owner = owners.user
-        self.context = context
-        import_lib = 'tiramisu.storage.{0}.setting'.format(storage_type)
+        self.context = weakref.ref(context)
+        import_lib = 'tiramisu.storage.{0}.setting'.format(storage.storage)
         self._p_ = __import__(import_lib, globals(), locals(), ['Settings'],
                               -1).Settings(storage)
 
@@ -235,7 +287,7 @@ class Settings(object):
             if opt is not None and _path is None:
                 _path = self._get_opt_path(opt)
             self._p_.reset_properties(_path)
-        self.context.cfgimpl_reset_cache()
+        self.context().cfgimpl_reset_cache()
 
     def _getproperties(self, opt=None, path=None, is_apply_req=True):
         if opt is None:
@@ -285,7 +337,7 @@ class Settings(object):
                 self._p_.reset_properties(path)
             else:
                 self._p_.setproperties(path, properties)
-        self.context.cfgimpl_reset_cache()
+        self.context().cfgimpl_reset_cache()
 
     #____________________________________________________________
     def validate_properties(self, opt_or_descr, is_descr, is_write, path,
@@ -325,7 +377,7 @@ class Settings(object):
             properties -= frozenset(('mandatory', 'frozen'))
         else:
             if 'mandatory' in properties and \
-                    not self.context.cfgimpl_get_values()._isempty(
+                    not self.context().cfgimpl_get_values()._isempty(
                         opt_or_descr, value):
                 properties.remove('mandatory')
             if is_write and 'everything_frozen' in self_properties:
@@ -442,8 +494,8 @@ class Settings(object):
                                              " '{0}' with requirement on: "
                                              "'{1}'").format(path, reqpath))
                 try:
-                    value = self.context._getattr(reqpath,
-                                                  force_permissive=True)
+                    value = self.context()._getattr(reqpath,
+                                                    force_permissive=True)
                 except PropertiesOptionError, err:
                     if not transitive:
                         continue
@@ -467,4 +519,4 @@ class Settings(object):
             return calc_properties
 
     def _get_opt_path(self, opt):
-        return self.context.cfgimpl_get_description().impl_get_path_by_opt(opt)
+        return self.context().cfgimpl_get_description().impl_get_path_by_opt(opt)