/usr/lib/python2.7/dist-packages/schema.py is in python-schema 0.6.5-1.
This file is owned by root:root, with mode 0o644.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 | """schema is a library for validating Python data structures, such as those
obtained from config-files, forms, external services or command-line
parsing, converted from JSON/YAML (or something else) to Python data-types."""
import re
__version__ = '0.6.5'
__all__ = ['Schema',
'And', 'Or', 'Regex', 'Optional',
'SchemaError',
'SchemaWrongKeyError',
'SchemaMissingKeyError',
'SchemaUnexpectedTypeError']
class SchemaError(Exception):
"""Error during Schema validation."""
def __init__(self, autos, errors=None):
self.autos = autos if type(autos) is list else [autos]
self.errors = errors if type(errors) is list else [errors]
Exception.__init__(self, self.code)
@property
def code(self):
"""
Removes duplicates values in auto and error list.
parameters.
"""
def uniq(seq):
"""
Utility function that removes duplicate.
"""
seen = set()
seen_add = seen.add
# This way removes duplicates while preserving the order.
return [x for x in seq if x not in seen and not seen_add(x)]
data_set = uniq(i for i in self.autos if i is not None)
error_list = uniq(i for i in self.errors if i is not None)
if error_list:
return '\n'.join(error_list)
return '\n'.join(data_set)
class SchemaWrongKeyError(SchemaError):
"""Error Should be raised when an unexpected key is detected within the
data set being."""
pass
class SchemaMissingKeyError(SchemaError):
"""Error should be raised when a mandatory key is not found within the
data set being vaidated"""
pass
class SchemaUnexpectedTypeError(SchemaError):
"""Error should be raised when a type mismatch is detected within the
data set being validated."""
pass
class And(object):
"""
Utility function to combine validation directives in AND Boolean fashion.
"""
def __init__(self, *args, **kw):
self._args = args
assert list(kw) in (['error'], [])
self._error = kw.get('error')
def __repr__(self):
return '%s(%s)' % (self.__class__.__name__,
', '.join(repr(a) for a in self._args))
def validate(self, data):
"""
Validate data using defined sub schema/expressions ensuring all
values are valid.
:param data: to be validated with sub defined schemas.
:return: returns validated data
"""
for s in [Schema(s, error=self._error) for s in self._args]:
data = s.validate(data)
return data
class Or(And):
"""Utility function to combine validation directives in a OR Boolean
fashion."""
def validate(self, data):
"""
Validate data using sub defined schema/expressions ensuring at least
one value is valid.
:param data: data to be validated by provided schema.
:return: return validated data if not validation
"""
x = SchemaError([], [])
for s in [Schema(s, error=self._error) for s in self._args]:
try:
return s.validate(data)
except SchemaError as _x:
x = _x
raise SchemaError(['%r did not validate %r' % (self, data)] + x.autos,
[self._error.format(data) if self._error else None] +
x.errors)
class Regex(object):
"""
Enables schema.py to validate string using regular expressions.
"""
# Map all flags bits to a more readable description
NAMES = ['re.ASCII', 're.DEBUG', 're.VERBOSE', 're.UNICODE', 're.DOTALL',
're.MULTILINE', 're.LOCALE', 're.IGNORECASE', 're.TEMPLATE']
def __init__(self, pattern_str, flags=0, error=None):
self._pattern_str = pattern_str
flags_list = [Regex.NAMES[i] for i, f in # Name for each bit
enumerate('{0:09b}'.format(flags)) if f != '0']
if flags_list:
self._flags_names = ', flags=' + '|'.join(flags_list)
else:
self._flags_names = ''
self._pattern = re.compile(pattern_str, flags=flags)
self._error = error
def __repr__(self):
return '%s(%r%s)' % (
self.__class__.__name__, self._pattern_str, self._flags_names
)
def validate(self, data):
"""
Validated data using defined regex.
:param data: data to be validated
:return: return validated data.
"""
e = self._error
try:
if self._pattern.search(data):
return data
else:
raise SchemaError('%r does not match %r' % (self, data), e)
except TypeError:
raise SchemaError('%r is not string nor buffer' % data, e)
class Use(object):
"""
For more general use cases, you can use the Use class to transform
the data while it is being validate.
"""
def __init__(self, callable_, error=None):
assert callable(callable_)
self._callable = callable_
self._error = error
def __repr__(self):
return '%s(%r)' % (self.__class__.__name__, self._callable)
def validate(self, data):
try:
return self._callable(data)
except SchemaError as x:
raise SchemaError([None] + x.autos,
[self._error.format(data)
if self._error else None] + x.errors)
except BaseException as x:
f = _callable_str(self._callable)
raise SchemaError('%s(%r) raised %r' % (f, data, x),
self._error.format(data)
if self._error else None)
COMPARABLE, CALLABLE, VALIDATOR, TYPE, DICT, ITERABLE = range(6)
def _priority(s):
"""Return priority for a given object."""
if type(s) in (list, tuple, set, frozenset):
return ITERABLE
if type(s) is dict:
return DICT
if issubclass(type(s), type):
return TYPE
if hasattr(s, 'validate'):
return VALIDATOR
if callable(s):
return CALLABLE
else:
return COMPARABLE
class Schema(object):
"""
Entry point of the library, use this class to instantiate validation
schema for the data that will be validated.
"""
def __init__(self, schema, error=None, ignore_extra_keys=False):
self._schema = schema
self._error = error
self._ignore_extra_keys = ignore_extra_keys
def __repr__(self):
return '%s(%r)' % (self.__class__.__name__, self._schema)
@staticmethod
def _dict_key_priority(s):
"""Return priority for a given key object."""
if isinstance(s, Optional):
return _priority(s._schema) + 0.5
return _priority(s)
def validate(self, data):
s = self._schema
e = self._error
flavor = _priority(s)
if flavor == ITERABLE:
data = Schema(type(s), error=e).validate(data)
o = Or(*s, error=e)
return type(data)(o.validate(d) for d in data)
if flavor == DICT:
data = Schema(dict, error=e).validate(data)
new = type(data)() # new - is a dict of the validated values
coverage = set() # matched schema keys
# for each key and value find a schema entry matching them, if any
sorted_skeys = sorted(s, key=self._dict_key_priority)
for key, value in data.items():
for skey in sorted_skeys:
svalue = s[skey]
try:
nkey = Schema(skey, error=e).validate(key)
except SchemaError:
pass
else:
nvalue = Schema(svalue, error=e).validate(value)
new[nkey] = nvalue
coverage.add(skey)
break
required = set(k for k in s if type(k) is not Optional)
if not required.issubset(coverage):
missing_keys = required - coverage
s_missing_keys = \
', '.join(repr(k) for k in sorted(missing_keys, key=repr))
raise \
SchemaMissingKeyError('Missing keys: ' + s_missing_keys, e)
if not self._ignore_extra_keys and (len(new) != len(data)):
wrong_keys = set(data.keys()) - set(new.keys())
s_wrong_keys = \
', '.join(repr(k) for k in sorted(wrong_keys, key=repr))
raise \
SchemaWrongKeyError(
'Wrong keys %s in %r' % (s_wrong_keys, data),
e.format(data) if e else None)
# Apply default-having optionals that haven't been used:
defaults = set(k for k in s if type(k) is Optional and
hasattr(k, 'default')) - coverage
for default in defaults:
new[default.key] = default.default
return new
if flavor == TYPE:
if isinstance(data, s):
return data
else:
raise SchemaUnexpectedTypeError(
'%r should be instance of %r' % (data, s.__name__),
e.format(data) if e else None)
if flavor == VALIDATOR:
try:
return s.validate(data)
except SchemaError as x:
raise SchemaError([None] + x.autos, [e] + x.errors)
except BaseException as x:
raise SchemaError(
'%r.validate(%r) raised %r' % (s, data, x),
self._error.format(data) if self._error else None)
if flavor == CALLABLE:
f = _callable_str(s)
try:
if s(data):
return data
except SchemaError as x:
raise SchemaError([None] + x.autos, [e] + x.errors)
except BaseException as x:
raise SchemaError(
'%s(%r) raised %r' % (f, data, x),
self._error.format(data) if self._error else None)
raise SchemaError('%s(%r) should evaluate to True' % (f, data), e)
if s == data:
return data
else:
raise SchemaError('%r does not match %r' % (s, data),
e.format(data) if e else None)
class Optional(Schema):
"""Marker for an optional part of the validation Schema."""
_MARKER = object()
def __init__(self, *args, **kwargs):
default = kwargs.pop('default', self._MARKER)
super(Optional, self).__init__(*args, **kwargs)
if default is not self._MARKER:
# See if I can come up with a static key to use for myself:
if _priority(self._schema) != COMPARABLE:
raise TypeError(
'Optional keys with defaults must have simple, '
'predictable values, like literal strings or ints. '
'"%r" is too complex.' % (self._schema,))
self.default = default
self.key = self._schema
def _callable_str(callable_):
if hasattr(callable_, '__name__'):
return callable_.__name__
return str(callable_)
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