frappy/secop/datatypes.py
Enrico Faulhaber bc3253a01a replace validators with datatypes
Change-Id: I446c4e14e24afa3f65e79c8b6e07eec3271532b0
2017-07-03 18:13:09 +02:00

410 lines
16 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 validated data types."""
from .errors import ProgrammingError
from collections import OrderedDict
# base class for all DataTypes
class DataType(object):
as_json = ['undefined']
def validate(self, value):
"""validate a external representation and return an internal one"""
raise NotImplemented
def export(self, value):
"""returns a python object fit for external serialisation or logging"""
raise NotImplemented
# goodie: if called, validate
def __call__(self, value):
return self.validate(value)
class FloatRange(DataType):
"""Restricted float type"""
def __init__(self, min=None, max=None):
self.min = None if min is None else float(min)
self.max = None if max is None else float(max)
# note: as we may compare to Inf all comparisons would be false
if (self.min or float('-inf')) <= (self.max or float('+inf')):
self.as_json = ['double', min, max]
else:
raise ValueError('Max must be larger then min!')
def validate(self, value):
try:
value = float(value)
except:
raise ValueError('Can not validate %r to float' % value)
if self.min is not None and value < self.min:
raise ValueError('%r should not be less then %s' % (value, self.min))
if self.max is not None and value > self.max:
raise ValueError('%r should not be greater than %s' % (value, self.max))
if None in (self.min, self.max):
return value
if self.min <= value <= self.max:
return value
raise ValueError('%r should be an float between %.3f and %.3f' %
(value, self.min, self.max))
def __repr__(self):
if self.max != None:
return "FloatRange(%r, %r)" % (float('-inf') if self.min is None else self.min, self.max)
if self.min != None:
return "FloatRange(%r)" % self.min
return "FloatRange()"
def export(self, value):
"""returns a python object fit for serialisation"""
return float(value)
class IntRange(DataType):
"""Restricted int type"""
def __init__(self, min=None, max=None):
self.min = int(min) if min is not None else min
self.max = int(max) if max is not None else max
if self.min is not None and self.max is not None and self.min > self.max:
raise ValueError('Max must be larger then min!')
self.as_json = ['int', self.min, self.max]
def validate(self, value):
try:
value = int(value)
if self.min is not None and value < self.min:
raise ValueError('%r should be an int between %d and %d' %
(value, self.min, self.max or 0))
if self.max is not None and value > self.max:
raise ValueError('%r should be an int between %d and %d' %
(value, self.min or 0, self.max))
return value
except:
raise ValueError('Can not validate %r to int' % value)
def __repr__(self):
if self.max is not None:
return "IntRange(%d, %d)" % (self.min, self.max)
if self.min is not None:
return "IntRange(%d)" % self.min
return "IntRange(%d)" % self.min
def export(self, value):
"""returns a python object fit for serialisation"""
return int(value)
class EnumType(DataType):
as_json = ['enum']
def __init__(self, *args, **kwds):
# enum keys are ints! check
self.entries = {}
num = 0
for arg in args:
if type(arg) != str:
print arg, type(arg)
raise ValueError('EnumType entries MUST be strings!')
self.entries[num] = arg
num += 1
for k, v in kwds.items():
v = int(v)
if v in self.entries:
raise ValueError('keyword argument %r=%d is already assigned %r', k, v, self.entries[v])
self.entries[v] = k
if len(self.entries) == 0:
raise ValueError('Empty enums ae not allowed!')
self.reversed = {}
for k,v in self.entries.items():
if v in self.reversed:
raise ValueError('Mapping for %r=%r is not Unique!', v, k)
self.reversed[v] = k
self.as_json = ['enum', self.reversed.copy()]
def __repr__(self):
return "EnumType(%s)" % ', '.join(['%s=%d' % (v,k) for k,v in self.entries.items()])
def export(self, value):
"""returns a python object fit for serialisation"""
if value in self.reversed:
return self.reversed[value]
if int(value) in self.entries:
return int(value)
raise ValueError('%r is not one of %s', str(value), ', '.join(self.reversed.keys()))
def validate(self, value):
"""return the validated (internal) value or raise"""
if value in self.reversed:
return value
if int(value) in self.entries:
return self.entries[int(value)]
raise ValueError('%r is not one of %s', str(value), ', '.join(map(str,self.entries.keys())))
class BLOBType(DataType):
def __init__(self, minsize=0, maxsize=None):
self.minsize = minsize
self.maxsize = maxsize
if minsize or maxsize:
self.as_json = ['blob', minsize, maxsize]
else:
self.as_json = ['blob']
if minsize is not None and maxsize is not None and minsize > maxsize:
raise ValueError('maxsize must be bigger than minsize!')
def __repr__(self):
if self.maxsize:
return 'BLOB(%s, %s)' % (str(self.minsize), str(self.maxsize))
if self.minsize:
return 'BLOB(%d)' % self.minsize
return 'BLOB()'
def validate(self, value):
"""return the validated (internal) value or raise"""
if type(value) not in [str, unicode]:
raise ValueError('%r has the wrong type!', value)
size = len(value)
if size < self.minsize:
raise ValueError('%r must be at least %d bytes long!', value, self.minsize)
if self.maxsize is not None:
if size > self.maxsize:
raise ValueError('%r must be at most %d bytes long!', value, self.maxsize)
return value
def export(self, value):
"""returns a python object fit for serialisation"""
return b'%s' % value
class StringType(DataType):
as_json = ['string']
def __init__(self, minsize=0, maxsize=None):
self.minsize = minsize
self.maxsize = maxsize
if (minsize, maxsize) == (0, None):
self.as_json = ['string']
else:
self.as_json = ['string', minsize, maxsize]
if minsize is not None and maxsize is not None and minsize > maxsize:
raise ValueError('maxsize must be bigger than minsize!')
def __repr__(self):
if self.maxsize:
return 'StringType(%s, %s)' % (str(self.minsize), str(self.maxsize))
if self.minsize:
return 'StringType(%d)' % str(self.minsize)
return 'StringType()'
def validate(self, value):
"""return the validated (internal) value or raise"""
if type(value) not in [str, unicode]:
raise ValueError('%r has the wrong type!', value)
size = len(value)
if size < self.minsize:
raise ValueError('%r must be at least %d bytes long!', value, self.minsize)
if self.maxsize is not None:
if size > self.maxsize:
raise ValueError('%r must be at most %d bytes long!', value, self.maxsize)
if '\0' in value:
raise ValueError('Strings are not allowed to embed a \\0! Use a Blob instead!')
return value
def export(self, value):
"""returns a python object fit for serialisation"""
return '%s' % value
# Bool is a special enum
class BoolType(DataType):
as_json = ['bool']
def __repr__(self):
return 'BoolType()'
def validate(self, value):
"""return the validated (internal) value or raise"""
if value in [0, '0', 'False', 'false', 'no', 'off', False]:
return False
if value in [1, '1', 'True', 'true', 'yes', 'on', True]:
return True
raise ValueError('%r is not a boolean value!', value)
def export(self, value):
"""returns a python object fit for serialisation"""
return True if self.validate(value) else False
#
# nested types
#
class ArrayOf(DataType):
def __init__(self, subtype, minsize_or_size=None, maxsize=None):
if maxsize is None:
maxsize = minsize_or_size
self.minsize = minsize_or_size
self.maxsize = maxsize
if self.minsize is not None and self.maxsize is not None and \
self.minsize > self.maxsize:
raise ValueError('minsize must be less than or equal to maxsize!')
if not isinstance(subtype, DataType):
raise ValueError('ArrayOf only works with DataType objs as first argument!')
self.subtype = subtype
self.as_json = ['array', self.subtype.as_json, self.minsize, self.maxsize]
if self.minsize is not None and self.minsize < 0:
raise ValueError('Minimum size must be >= 0!')
if self.maxsize is not None and self.maxsize < 1:
raise ValueError('Maximum size must be >= 1!')
if self.minsize is not None and self.maxsize is not None and self.minsize > self.maxsize:
raise ValueError('Maximum size must be >= Minimum size')
def __repr__(self):
return 'ArrayOf(%s, %s, %s)' % (repr(self.subtype), self.minsize, self.maxsize)
def validate(self, value):
"""validate a external representation to an internal one"""
if isinstance(value, (tuple, list)):
# check number of elements
if self.minsize is not None and len(value) < self.minsize:
raise ValueError('Array too small, needs at least %d elements!', self.minsize)
if self.maxsize is not None and len(value) > self.maxsize:
raise ValueError('Array too big, holds at most %d elements!', self.minsize)
# apply subtype valiation to all elements and return as list
return [self.subtype.validate(elem) for elem in value]
raise ValueError('Can not convert %s to ArrayOf DataType!', repr(value))
def export(self, value):
"""returns a python object fit for serialisation"""
return [self.subtype.export(elem) for elem in value]
class TupleOf(DataType):
def __init__(self, *subtypes):
if not subtypes:
raise ValueError('Empty tuples are not allowed!')
for subtype in subtypes:
if not isinstance(subtype, DataType):
raise ValueError('TupleOf only works with DataType objs as arguments!')
self.subtypes = subtypes
self.as_json = ['tuple', [subtype.as_json for subtype in subtypes]]
def __repr__(self):
return 'TupleOf(%s)' % ', '.join([repr(st) for st in self.subtypes])
def validate(self, value):
"""return the validated value or raise"""
# keep the ordering!
try:
if len(value) != len(self.subtypes):
raise ValueError('Illegal number of Arguments! Need %d arguments.', len(self.subtypes))
# validate elements and return as list
return [sub.validate(elem) for sub,elem in zip(self.subtypes, value)]
except Exception as exc:
raise ValueError('Can not validate:', str(exc))
def export(self, value):
"""returns a python object fit for serialisation"""
return [sub.export(elem) for sub,elem in zip(self.subtypes, value)]
class StructOf(DataType):
def __init__(self, **named_subtypes):
if not named_subtypes:
raise ValueError('Empty structs are not allowed!')
for name, subtype in named_subtypes.items():
if not isinstance(subtype, DataType):
raise ProgrammingError('StructOf only works with named DataType objs as keyworded arguments!')
if not isinstance(name, (str, unicode)):
raise ProgrammingError('StructOf only works with named DataType objs as keyworded arguments!')
self.named_subtypes = named_subtypes
self.as_json = ['struct', dict((n,s.as_json) for n,s in named_subtypes.items())]
def __repr__(self):
return 'StructOf(%s)' % ', '.join(['%s=%s'%(n,repr(st)) for n,st in self.named_subtypes.iteritems()])
def validate(self, value):
"""return the validated value or raise"""
try:
if len(value.keys()) != len(self.named_subtypes.keys()):
raise ValueError('Illegal number of Arguments! Need %d arguments.', len(self.namd_subtypes.keys()))
# validate elements and return as dict
return dict((str(k), self.named_subtypes[k].validate(v))
for k,v in value.items())
except Exception as exc:
raise ValueError('Can not validate %s: %s', repr(value),str(exc))
def export(self, value):
"""returns a python object fit for serialisation"""
if len(value.keys()) != len(self.named_subtypes.keys()):
raise ValueError('Illegal number of Arguments! Need %d arguments.', len(self.namd_subtypes.keys()))
return dict((str(k),self.named_subtypes[k].export(v))
for k,v in value.items())
# XXX: derive from above classes automagically!
DATATYPES = dict(
bool = lambda : BoolType(),
int = lambda _min=None, _max=None: IntRange(_min, _max),
double = lambda _min=None, _max=None: FloatRange(_min, _max),
blob = lambda _min=None, _max=None: BLOBType(_min, _max),
string = lambda _min=None, _max=None: StringType(_min, _max),
array = lambda subtype, _min=None, _max=None: ArrayOf(get_datatype(subtype), _min, _max),
tuple = lambda subtypes: TupleOf(*map(get_datatype,subtypes)),
enum = lambda kwds: EnumType(**kwds),
struct = lambda named_subtypes: StructOf(**dict((n,get_datatype(t)) for n,t in named_subtypes.items())),
)
# probably not needed...
def export_datatype(datatype):
if datatype is None:
return datatype
return datatype.as_json
# important for getting the right datatype from formerly jsonified descr.
def get_datatype(json):
if json is None:
return json
if not isinstance(json, list):
raise ValueError('Argument must be a properly formatted list!')
if len(json)<1:
raise ValueError('can not validate %r', json)
base = json[0]
if base in DATATYPES:
if base in ('enum', 'struct'):
if len(json) > 1:
args = json[1:]
else:
args = []
else:
args = json[1:]
try:
return DATATYPES[base](*args)
except (TypeError, AttributeError) as exc:
raise ValueError('Invalid datatype descriptor')
raise ValueError('can not validate %r', json)