added class-based leaf filters

lib/smisk/mvc/decorators.py

@@ -6,71 +6,98 @@
 __all__ = ['expose', 'hide', 'leaf_filter']
 
 def expose(slug=None, template=None, formats=None, delegates=False, methods=None):
-  '''Explicitly expose a function, optionally configure how it is exposed.
-  '''
-  def entangle(func):
-    # Note: We do not add default values (i.e. methods = None) because we can not gurantee
-    #       that every leaf called has been @expose'd, so we need to check for attribute
-    #       existance anyway outside of this scope.
-    
-    # Slug
-    if slug is not None:
-      # Slug might be the function if decorator called without ()
-      if isinstance(slug, basestring):
-        func.slug = unicode(slug)
-      elif isinstance(slug, unicode):
-        func.slug = slug
-    
-    # Delegates to other leafs up the class hierarchy?
-    if delegates is not None:
-      func.delegates = bool(delegates)
-    
-    # Template
-    if template is not None:
-      func.template = unicode(template)
-    
-    # Formats
-    if formats is not None:
-      if isinstance(formats, (list, tuple)):
-        func.formats = formats
-      else:
-        func.formats = (formats,)
-      for s in func.formats:
-        if not isinstance(s, basestring):
-          raise TypeError('formats must be a tuple or list of strings, alternatively a single string')
-    
-    # Methods
-    if methods is not None:
-      if isinstance(methods, (list, tuple)):
-        func.methods = methods
-      else:
-        func.methods = (methods,)
-      for s in func.methods:
-        if not isinstance(s, basestring):
-          raise TypeError('methods must be a tuple or list of strings, alternatively a single string')
-      func.methods = [s.upper() for s in func.methods]
-    
-    return func
-  
-  if isinstance(slug, (types.FunctionType, types.MethodType)):
-    return entangle(slug)
-  return entangle
+	'''Explicitly expose a function, optionally configure how it is exposed.
+	'''
+	def entangle(func):
+		# Note: We do not add default values (i.e. methods = None) because we can not gurantee
+		#			 that every leaf called has been @expose'd, so we need to check for attribute
+		#			 existance anyway outside of this scope.
+		
+		# Slug
+		if slug is not None:
+			# Slug might be the function if decorator called without ()
+			if isinstance(slug, basestring):
+				func.slug = unicode(slug)
+			elif isinstance(slug, unicode):
+				func.slug = slug
+		
+		# Delegates to other leafs up the class hierarchy?
+		if delegates is not None:
+			func.delegates = bool(delegates)
+		
+		# Template
+		if template is not None:
+			func.template = unicode(template)
+		
+		# Formats
+		if formats is not None:
+			if isinstance(formats, (list, tuple)):
+				func.formats = formats
+			else:
+				func.formats = (formats,)
+			for s in func.formats:
+				if not isinstance(s, basestring):
+					raise TypeError('formats must be a tuple or list of strings, alternatively a single string')
+		
+		# Methods
+		if methods is not None:
+			if isinstance(methods, (list, tuple)):
+				func.methods = methods
+			else:
+				func.methods = (methods,)
+			for s in func.methods:
+				if not isinstance(s, basestring):
+					raise TypeError('methods must be a tuple or list of strings, alternatively a single string')
+			func.methods = [s.upper() for s in func.methods]
+		
+		return func
+	
+	if isinstance(slug, (types.FunctionType, types.MethodType)):
+		return entangle(slug)
+	return entangle
 
 
 def hide(func=None):
-  def entangle(func):
-    func.hidden = True
-    return func
-  if isinstance(func, (types.FunctionType, types.MethodType)):
-    return entangle(func)
-  return entangle
+	def entangle(func):
+		func.hidden = True
+		return func
+	if isinstance(func, (types.FunctionType, types.MethodType)):
+		return entangle(func)
+	return entangle
 
 
 def leaf_filter(filter):
-  def entangle(leaf, *va, **kw):
-    def f(*va, **kw):
-      return filter(leaf, *va, **kw)
-    f.parent_leaf = leaf
-    return f
-  entangle.__name__ = filter.__name__+'_leaf_filter'
-  return entangle
+	def entangle(leaf, *va, **kw):
+		def f(*va, **kw):
+			return filter(leaf, *va, **kw)
+		f.parent_leaf = leaf
+		return f
+	entangle.__name__ = filter.__name__+'_leaf_filter'
+	return entangle
+
+class LeafFilter(object):
+	'''Leaf filter factory baseclass
+	
+	Used like this:
+	
+		myf = MySubclass()
+		...
+		@myf
+		def some_leaf...
+	
+	'''
+	def filter_proxy(self, leaf, filter):
+		def f(*va, **kw):
+			return filter(leaf, *va, **kw)
+		f.parent_leaf = leaf
+		f.__name__ = leaf.__name__+'_with_'+self.__class__.__name__+'_'+filter.__name__
+		return f
+
+	def __call__(self, leaf):
+		return self.filter_proxy(leaf, self.filter)
+
+	def filter(self):
+		raise NotImplementedError('filter')
+
+
+