"""
Constraints
"""
class BadValue(ValueError):
def __init__(self, desc, obj, col, value, *args):
self.desc = desc
self.col = col
# I want these objects to be garbage-collectable, so
# I just keep their repr:
self.obj = repr(obj)
self.value = repr(value)
fullDesc = "%s.%s %s (you gave: %s)" \
% (obj, col.name, desc, value)
ValueError.__init__(self, fullDesc, *args)
def isString(obj, col, value):
if not isinstance(value, str):
raise BadValue("only allows strings", obj, col, value)
def notNull(obj, col, value):
if value is None:
raise BadValue("is defined NOT NULL", obj, col, value)
def isInt(obj, col, value):
if not isinstance(value, (int, long)):
raise BadValue("only allows integers", obj, col, value)
def isFloat(obj, col, value):
if not isinstance(value, (int, long, float)):
raise BadValue("only allows floating point numbers", obj, col, value)
def isBool(obj, col, value):
if not isinstance(value, bool):
raise BadValue("only allows booleans", obj, col, value)
class InList:
def __init__(self, l):
self.list = l
def __call__(self, obj, col, value):
if value not in self.list:
raise BadValue("accepts only values in %s" % repr(self.list),
obj, col, value)
class MaxLength:
def __init__(self, length):
self.length = length
def __call__(self, obj, col, value):
try:
length = len(value)
except TypeError:
raise BadValue("object does not have a length",
obj, col, value)
if length > self.length:
raise BadValue("must be shorter in length than %s"
% self.length,
obj, col, value)
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