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104def get_normalized_func_name(func):
func = func.upper()
if func[-1] == '_':
return func[:-1]
return func
def _stringify_args(*args):
mod_args = []
for arg in args:
if isinstance(arg, basestring):
mod_args.append('"{}"'.format(arg))
else:
mod_args.append(arg)
return mod_args
class _MetaField(type):
"""
Maintain a single instance for same field name
"""
instances = {}
def __call__(cls, field_name):
if field_name in _MetaField.instances:
return _MetaField.instances[field_name]
instance = type.__call__(cls, field_name)
_MetaField.instances[field_name] = instance
return instance
class Field(object):
__metaclass__ = _MetaField
_one_arg = ('eq', 'ne', 'gt', 'lt', 'ge', 'le', 'startswith')
# _two_arg = ('between',)
_multi_arg = ('between', 'in_', 'contains_any', 'contains_all', 'contains')
@classmethod
def __one_arg_func(cls, method, field):
def _func(*args):
if len(args) != 1:
raise ValueError(
'{} accepts only one argument.'.format(method))
return {get_normalized_func_name(method): {field: args[0]}}
return _func
@classmethod
def __multi_arg_func(cls, method, field):
def _func(*args):
if len(args) < 1:
raise ValueError('No arguments given')
if len(args) == 1:
return {get_normalized_func_name(method): {field: args[0]}}
return {get_normalized_func_name(method): {field: args}}
return _func
def __getattr__(self, attr):
if attr in self._one_arg:
return self.__one_arg_func(attr, self.field)
elif attr in self._multi_arg:
return self.__multi_arg_func(attr, self.field)
else:
raise AttributeError('{} not found'.format(attr))
def __init__(self, field):
self.field = field
def __eq__(self, rhs):
return self.eq(rhs)
def __ne__(self, rhs):
return self.ne(rhs)
def __lt__(self, rhs):
return self.lt(rhs)
def __le__(self, rhs):
return self.le(rhs)
def __gt__(self, rhs):
return self.gt(rhs)
def __ge__(self, rhs):
return self.ge(rhs)
def __lshift__(self, rhs):
return self.in_(*rhs)
def AND(*args):
if len(args) < 1:
raise ValueError('AND accepts more than Zero argumnets')
# return "AND({})".format(", ".join(args))
return {"AND": args}
def OR(*args):
if len(args) < 1:
raise ValueError('AND accepts more than Zero argumnets')
# return "OR({})".format(", ".join(args))
return {"OR": args}