class ApiNodeMetaclass(type):
parent_class = writeonce(
None,
writeonce_msg=
u'Duplicate in API tree: %(instance)s already has parent %(old_value)s though %(value)s can not be set as new parent'
)
def __new__(cls, name, parents, dct):
ret = super(ApiNodeMetaclass, cls).__new__(cls, name, parents, dct)
# Initializing internal class attributes
ret._serializers_preparations = None
for node_name, node_class in ret.iter_children():
node_class.parent_class = ret
if not node_class.name:
node_class.name = node_name.lower()
ret.prepare_serializers()
return ret
@property
def urls(cls):
cls.get_root_class() # check for loops
return cls.get_urls()
def __str__(cls):
if not hasattr(cls, '_strval'):
s = cls.__name__
node = cls
i = 0
N = 10
while node.parent_class is not None and i < N:
s = node.parent_class.__name__ + '.' + s
node = node.parent_class
i += 1
if i == N:
s = ' ...%s' % s
else:
s = '.%s' % s
cls._strval = '%s%s' % (node.__module__, s)
return cls._strval
class A(object):
x = writeonce()
class M(type):
x = writeonce()
class A(object):
x = writeonce(default)
class B(A):
x = writeonce() # explicit override - so it's ok
class A(object):
x = writeonce(writeonce_msg='qwe-%(name)s-%(instance)s-%(value)s-%(old_value)s')
def __str__(self):
return 'a'