frappy/secop/validators.py
Alexander Lenz d442da0789 Stub debug client gui.
Change-Id: Ib422c66bc36245e1fc3c450765d7555da5c8dda0
2017-01-19 10:04:16 +01:00

260 lines
8.5 KiB
Python

# -*- coding: utf-8 -*-
# *****************************************************************************
#
# This program is free software; you can redistribute it and/or modify it under
# the terms of the GNU General Public License as published by the Free Software
# Foundation; either version 2 of the License, or (at your option) any later
# version.
#
# This program is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
# FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
# details.
#
# You should have received a copy of the GNU General Public License along with
# this program; if not, write to the Free Software Foundation, Inc.,
# 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
#
# Module authors:
# Enrico Faulhaber <enrico.faulhaber@frm2.tum.de>
#
# *****************************************************************************
"""Define validators."""
# a Validator returns a validated object or raises an ValueError
# easy python validators: int(), float(), str()
# also validators should have a __repr__ returning a 'python' string
# which recreates them
# if a validator does a mapping, it normally maps to the external representation (used for print/log/protocol/...)
# to get the internal representation (for the code), call method convert
class ProgrammingError(Exception):
pass
class Validator(object):
# list of tuples: (name, converter)
params = []
valuetype = float
def __init__(self, *args, **kwds):
plist = self.params[:]
if len(args) > len(plist):
raise ProgrammingError('%s takes %d parameters only (%d given)' % (
self.__class__.__name__,
len(plist), len(args)))
for pval in args:
pname, pconv = plist.pop(0)
if pname in kwds:
raise ProgrammingError('%s: positional parameter %s als given '
'as keyword!' % (
self.__class__.__name__,
pname))
self.__dict__[pname] = pconv(pval)
for pname, pconv in plist:
if pname in kwds:
pval = kwds.pop(pname)
self.__dict__[pname] = pconv(pval)
else:
raise ProgrammingError('%s: param %s left unspecified!' % (
self.__class__.__name__,
pname))
if kwds:
raise ProgrammingError('%s got unknown arguments: %s' % (
self.__class__.__name__,
', '.join(list(kwds.keys()))))
def __repr__(self):
params = ['%s=%r' % (pn[0], self.__dict__[pn[0]])
for pn in self.params]
return ('%s(%s)' % (self.__class__.__name__, ', '.join(params)))
def __call__(self, value):
return self.check(self.valuetype(value))
def convert(self, value):
# transforms the 'internal' representation into the 'external'
return self.valuetype(value)
class floatrange(Validator):
params = [('lower', float), ('upper', float)]
def check(self, value):
if self.lower <= value <= self.upper:
return value
raise ValueError('Floatrange: value %r must be within %f and %f' %
(value, self.lower, self.upper))
class intrange(Validator):
params = [('lower', int), ('upper', int)]
valuetype = int
def check(self, value):
if self.lower <= value <= self.upper:
return value
raise ValueError('Intrange: value %r must be within %f and %f' %
(value, self.lower, self.upper))
class positive(Validator):
def check(self, value):
if value > 0:
return value
raise ValueError('Value %r must be > 0!' % value)
class nonnegative(Validator):
def check(self, value):
if value >= 0:
return value
raise ValueError('Value %r must be >= 0!' % value)
class array(Validator):
"""integral amount of data-elements which are described by the SAME validator
The size of the array can also be described by an validator
"""
valuetype = list
params = [('size', lambda x: x),
('datatype', lambda x: x)]
def check(self, values):
requested_size = len(values)
try:
allowed_size = self.size(requested_size)
except ValueError as e:
raise ValueError(
'illegal number of elements %d, need %r: (%s)' %
(requested_size, self.size, e))
if requested_size != allowed_size:
raise ValueError(
'need %d elements (got %d)' %
(allowed_size, requested_size))
# apply data-type validator to all elements and return
res = []
for idx, el in enumerate(values):
try:
res.append(self.datatype(el))
except ValueError as e:
raise ValueError(
'Array Element %s (=%r) not conforming to %r: (%s)' %
(idx, el, self.datatype, e))
return res
# more complicated validator may not be able to use validator base class
class vector(object):
"""fixed length, eache element has its own validator"""
def __init__(self, *args):
self.validators = args
self.argstr = ', '.join([validator_to_str(e) for e in args])
def __call__(self, args):
if len(args) != len(self.validators):
raise ValueError('Vector: need exactly %d elementes (got %d)' %
len(self.validators), len(args))
return tuple(v(e) for v, e in zip(self.validators, args))
def __repr__(self):
return ('%s(%s)' % (self.__class__.__name__, self.argstr))
class record(object):
"""fixed length, eache element has its own name and validator"""
def __init__(self, **kwds):
self.validators = args
self.argstr = ', '.join([validator_to_str(e) for e in kwds.items()])
def __call__(self, arg):
if len(args) != len(self.validators):
raise ValueError('Vector: need exactly %d elementes (got %d)' %
len(self.validators), len(args))
return tuple(v(e) for v, e in zip(self.validators, args))
def __repr__(self):
return ('%s(%s)' % (self.__class__.__name__, self.argstr))
class oneof(object):
"""needs to comply with one of the given validators/values"""
def __init__(self, *args):
self.oneof = args
self.argstr = ', '.join([validator_to_str(e) for e in args])
def __call__(self, arg):
for v in self.oneof:
if callable(v):
try:
if (v == int) and (float(arg) != int(arg)):
continue
return v(arg)
except ValueError:
pass # try next validator
elif v == arg:
return v
raise ValueError('Oneof: %r should be one of: %s' % (arg, self.argstr))
def __repr__(self):
return ('%s(%s)' % (self.__class__.__name__, self.argstr))
class enum(object):
def __init__(self, *args, **kwds):
self.mapping = {}
# use given kwds directly
self.mapping.update(kwds)
# enumerate args
i = -1
args = list(args)
while args:
i += 1
if i in self.mapping:
continue
self.mapping[args.pop(0)] = i
# generate reverse mapping too for use by protocol
self.revmapping = {}
for k, v in self.mapping.items():
self.revmapping[v] = k
def __call__(self, obj):
try:
obj = int(obj)
except ValueError:
pass
if obj in self.mapping:
return obj
if obj in self.revmapping:
return self.revmapping[obj]
raise ValueError("%r should be one of %r" %
(obj, list(self.mapping.keys())))
def __repr__(self):
params = ['%s=%r' % (mname, mval)
for mname, mval in self.mapping.items()]
return ('%s(%s)' % (self.__class__.__name__, ', '.join(params)))
def convert(self, arg):
return self.mapping.get(arg, arg)
def validator_to_str(validator):
return str(validator) if not isinstance(validator, type) \
else validator.__name__
def validator_from_str(validator_str):
return eval(validator_str)