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-rw-r--r--netlib/stateobject.py80
1 files changed, 0 insertions, 80 deletions
diff --git a/netlib/stateobject.py b/netlib/stateobject.py
deleted file mode 100644
index c2ef2cd4..00000000
--- a/netlib/stateobject.py
+++ /dev/null
@@ -1,80 +0,0 @@
-from types import ClassType
-
-
-class StateObject:
- def _get_state(self):
- raise NotImplementedError
-
- def _load_state(self, state):
- raise NotImplementedError
-
- @classmethod
- def _from_state(cls, state):
- raise NotImplementedError
-
- def __eq__(self, other):
- try:
- return self._get_state() == other._get_state()
- except AttributeError: # we may compare with something that's not a StateObject
- return False
-
-
-class SimpleStateObject(StateObject):
- """
- A StateObject with opionated conventions that tries to keep everything DRY.
-
- Simply put, you agree on a list of attributes and their type.
- Attributes can either be primitive types(str, tuple, bool, ...) or StateObject instances themselves.
- SimpleStateObject uses this information for the default _get_state(), _from_state(s) and _load_state(s) methods.
- Overriding _get_state or _load_state to add custom adjustments is always possible.
- """
-
- _stateobject_attributes = None # none by default to raise an exception if definition was forgotten
- """
- An attribute-name -> class-or-type dict containing all attributes that should be serialized
- If the attribute is a class, this class must be a subclass of StateObject.
- """
-
- def _get_state(self):
- return {attr: self.__get_state_attr(attr, cls)
- for attr, cls in self._stateobject_attributes.iteritems()}
-
- def __get_state_attr(self, attr, cls):
- """
- helper for _get_state.
- returns the value of the given attribute
- """
- if getattr(self, attr) is None:
- return None
- if isinstance(cls, ClassType):
- return getattr(self, attr)._get_state()
- else:
- return getattr(self, attr)
-
- def _load_state(self, state):
- for attr, cls in self._stateobject_attributes.iteritems():
- self.__load_state_attr(attr, cls, state)
-
- def __load_state_attr(self, attr, cls, state):
- """
- helper for _load_state.
- loads the given attribute from the state.
- """
- if state[attr] is not None: # First, catch None as value.
- if isinstance(cls, ClassType): # Is the attribute a StateObject itself?
- assert issubclass(cls, StateObject)
- curr = getattr(self, attr)
- if curr: # if the attribute is already present, delegate to the objects ._load_state method.
- curr._load_state(state[attr])
- else: # otherwise, create a new object.
- setattr(self, attr, cls._from_state(state[attr]))
- else:
- setattr(self, attr, cls(state[attr]))
- else:
- setattr(self, attr, None)
-
- @classmethod
- def _from_state(cls, state):
- f = cls() # the default implementation assumes an empty constructor. Override accordingly.
- f._load_state(state)
- return f \ No newline at end of file