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Fixed various problems with <registry.py>

Ed L authored on 03/03/2012 23:31:34
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registry.py
History View file @ 7e90196
... ... 
@@ -32,57 +32,43 @@ import contextlib
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 import functools
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 class CallableGeneratorContextManager(contextlib.GeneratorContextManager):
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+	'''A subclass of :py:class:`contextlib.GeneratorContextManager` which can be called
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+
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+	Basically, this exists to avoid unecessary hassles with object methods which need special treatment'''
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 	def __call__(self, *a, **kw):
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+		'''Enter self's context and call the object returned by __enter__'''
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 		with self as obj:
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 			return obj(*a, **kw)
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-try:
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-	from contextlib import contextmanager
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-except:
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-	def contextmanager(func):
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- 	  """@contextmanager decorator.
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-
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-    Typical usage:
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-
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-        @contextmanager
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-        def some_generator(<arguments>):
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-            <setup>
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-            try:
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-                yield <value>
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-            finally:
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-                <cleanup>
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-
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-    This makes this:
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-
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-        with some_generator(<arguments>) as <variable>:
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-            <body>
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-
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-    equivalent to this:
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-        <setup>
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-        try:
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-            <variable> = <value>
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-            <body>
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-        finally:
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-            <cleanup>
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-
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-    """
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-    @functools.wraps(func)
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-    def helper(*args, **kwds):
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-        return CallableGeneratorContextManager(func(*args, **kwds))
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-    return helper
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+#NOTE: (ed) this is ripped out of contextlib but I've replaced contextlib.GeneratorContextManager with the previous class
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+def contextmanager(func):
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+	'''see documentation for :py:class:`contextlib.GeneratorContextManager`'''
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+	@functools.wraps(func)
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+	def helper(*args, **kwds):
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+		return CallableGeneratorContextManager(func(*args, **kwds))
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+		# ^^^ This is the only line diferent from contextlib.contextmanager
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+	return helper
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 class RegisteredObj(object):
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+	'''Interface definition for :py:attr:`Registry.child_class`'''
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 	def __init__(self, name, *args):
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 		self.name = name
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 	def update(self, other):
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+		'''override me'''
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 		pass
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 def make_ctxt_manager(name):
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+	'''create a factory method for making and registering objects suitable to be registered in
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+	the Registry.
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+
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+	:param str name: The name of the factory method
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+	:return: A contextmanager
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+	'''
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 	@contextmanager
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-	def _inner(self, name, *args):
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-		obj = self.registry.get(name) if name in self.registry else self.child_class(name, *args)
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+	def _inner(self, name, *args, **kwargs):
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+		obj = self.registry.get(name) if name in self.registry else self.child_class(name, *args, **kwargs)
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 		yield obj
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 		if obj.name not in self.registry:
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 			self.register(obj)
... ... 
@@ -92,6 +78,8 @@ def make_ctxt_manager(name):
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 import threading
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 class Registry(object):
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+	#: The kind of object to be stored in the registry
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+	#: must, as a minimum implement the :py:class:`RegisteredObj` interface
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 	child_class = None
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 	def __setitem__(self, name, value):
... ... 
@@ -119,6 +107,12 @@ class Registry(object):
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 	_init_lock = threading.RLock()
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 	@staticmethod
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 	def setup(cls):
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+		'''Decorate the registry with this, this sets the 'registry' attribute to an
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+		empty dictionary and a factory function for creating child objects.
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+
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+		The name of the factory function is that of the class the registry registers,
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+		but lowercase'''
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+
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 		with cls._init_lock:
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 			factory_name = cls.child_class.__name__.lower()
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 			setattr(cls, factory_name, make_ctxt_manager(factory_name))
... ... 
@@ -139,6 +133,8 @@ class Registry(object):
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 		return result
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+### DEMO, read this for a practical example of how the above works:
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+
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 class DataObj(RegisteredObj):
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 	def __init__(self, name, a):
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 		RegisteredObj.__init__(self, name)