bindings/python/bt2/values.py

   1 # The MIT License (MIT)
   2 #
   3 # Copyright (c) 2016 Philippe Proulx <pproulx@efficios.com>
   4 #
   5 # Permission is hereby granted, free of charge, to any person obtaining a copy
   6 # of this software and associated documentation files (the "Software"), to deal
   7 # in the Software without restriction, including without limitation the rights
   8 # to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   9 # copies of the Software, and to permit persons to whom the Software is
  10 # furnished to do so, subject to the following conditions:
  11 #
  12 # The above copyright notice and this permission notice shall be included in
  13 # all copies or substantial portions of the Software.
  14 #
  15 # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16 # IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17 # FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  18 # AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19 # LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  20 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  21 # THE SOFTWARE.
  22
  23 from bt2 import native_bt, object, utils
  24 import collections.abc
  25 import functools
  26 import numbers
  27 import math
  28 import abc
  29 import bt2
  30
  31
  32 def _handle_status(status, obj_name):
  33     if status >= 0:
  34         return
  35
  36     if status == native_bt.VALUE_STATUS_FROZEN:
  37         raise bt2.FrozenError('{} value object is frozen'.format(obj_name))
  38     elif status == native_bt.VALUE_STATUS_INVAL:
  39         # In practice, this should never happen, because arguments
  40         # should always be validated in this Python module before
  41         # calling the native functions.
  42         raise ValueError('unexpected invalid argument')
  43     else:
  44         # In practice, this should never happen, because arguments
  45         # should always be validated in this Python module before
  46         # calling the native functions.
  47         raise RuntimeError('unexpected error')
  48
  49
  50 def _create_from_ptr(ptr):
  51     if ptr is None or ptr == native_bt.value_null:
  52         return
  53
  54     typeid = native_bt.value_get_type(ptr)
  55     return _TYPE_TO_OBJ[typeid]._create_from_ptr(ptr)
  56
  57
  58 def create_value(value):
  59     if value is None:
  60         # null value object
  61         return
  62
  63     if isinstance(value, _Value):
  64         return value
  65
  66     if isinstance(value, bool):
  67         return BoolValue(value)
  68
  69     if isinstance(value, int):
  70         return IntegerValue(value)
  71
  72     if isinstance(value, float):
  73         return FloatValue(value)
  74
  75     if isinstance(value, str):
  76         return StringValue(value)
  77
  78     try:
  79         return MapValue(value)
  80     except:
  81         pass
  82
  83     try:
  84         return ArrayValue(value)
  85     except:
  86         pass
  87
  88     raise TypeError("cannot create value object from '{}' object".format(value.__class__.__name__))
  89
  90
  91 class _Value(object._Object, object._Freezable, metaclass=abc.ABCMeta):
  92     def __init__(self, ptr):
  93         super().__init__(ptr)
  94
  95     def __eq__(self, other):
  96         if other is None:
  97             # self is never the null value object
  98             return False
  99
 100         # try type-specific comparison first
 101         spec_eq = self._spec_eq(other)
 102
 103         if spec_eq is not None:
 104             return spec_eq
 105
 106         if not isinstance(other, _Value):
 107             # not comparing apples to apples
 108             return False
 109
 110         # fall back to native comparison function
 111         return native_bt.value_compare(self._ptr, other._ptr)
 112
 113     def __ne__(self, other):
 114         return not (self == other)
 115
 116     @abc.abstractmethod
 117     def _spec_eq(self, other):
 118         pass
 119
 120     def _handle_status(self, status):
 121         _handle_status(status, self._NAME)
 122
 123     def _check_create_status(self, ptr):
 124         if ptr is None:
 125             raise bt2.CreationError('cannot create {} value object'.format(self._NAME.lower()))
 126
 127     def _is_frozen(self):
 128         return native_bt.value_is_frozen(self._ptr)
 129
 130     def _freeze(self):
 131         status = native_bt.value_freeze(self._ptr)
 132         self._handle_status(status)
 133
 134
 135 class _BasicCopy:
 136     def __copy__(self):
 137         return self.__class__(self.value)
 138
 139     def __deepcopy__(self, memo):
 140         copy = self.__copy__()
 141         memo[id(self)] = copy
 142         return copy
 143
 144
 145 @functools.total_ordering
 146 class _NumericValue(_Value, _BasicCopy):
 147     @staticmethod
 148     def _extract_value(other):
 149         if isinstance(other, _NumericValue):
 150             return other.value
 151
 152         if other is True or other is False:
 153             return other
 154
 155         if isinstance(other, numbers.Integral):
 156             return int(other)
 157
 158         if isinstance(other, numbers.Real):
 159             return float(other)
 160
 161         if isinstance(other, numbers.Complex):
 162             return complex(other)
 163
 164         raise TypeError("'{}' object is not a number object".format(other.__class__.__name__))
 165
 166     def __int__(self):
 167         return int(self.value)
 168
 169     def __float__(self):
 170         return float(self.value)
 171
 172     def __str__(self):
 173         return str(self.value)
 174
 175     def __lt__(self, other):
 176         if not isinstance(other, numbers.Number):
 177             raise TypeError('unorderable types: {}() < {}()'.format(self.__class__.__name__,
 178                                                                     other.__class__.__name__))
 179
 180         return self.value < float(other)
 181
 182     def __le__(self, other):
 183         if not isinstance(other, numbers.Number):
 184             raise TypeError('unorderable types: {}() <= {}()'.format(self.__class__.__name__,
 185                                                                      other.__class__.__name__))
 186
 187         return self.value <= float(other)
 188
 189     def _spec_eq(self, other):
 190         return
 191
 192     def __eq__(self, other):
 193         if not isinstance(other, numbers.Number):
 194             return False
 195
 196         return self.value == complex(other)
 197
 198     def __rmod__(self, other):
 199         return self._extract_value(other) % self.value
 200
 201     def __mod__(self, other):
 202         return self.value % self._extract_value(other)
 203
 204     def __rfloordiv__(self, other):
 205         return self._extract_value(other) // self.value
 206
 207     def __floordiv__(self, other):
 208         return self.value // self._extract_value(other)
 209
 210     def __round__(self, ndigits=None):
 211         if ndigits is None:
 212             return round(self.value)
 213         else:
 214             return round(self.value, ndigits)
 215
 216     def __ceil__(self):
 217         return math.ceil(self.value)
 218
 219     def __floor__(self):
 220         return math.floor(self.value)
 221
 222     def __trunc__(self):
 223         return int(self.value)
 224
 225     def __abs__(self):
 226         return abs(self.value)
 227
 228     def __add__(self, other):
 229         return self.value + self._extract_value(other)
 230
 231     def __radd__(self, other):
 232         return self.__add__(other)
 233
 234     def __neg__(self):
 235         return -self.value
 236
 237     def __pos__(self):
 238         return +self.value
 239
 240     def __mul__(self, other):
 241         return self.value * self._extract_value(other)
 242
 243     def __rmul__(self, other):
 244         return self.__mul__(other)
 245
 246     def __truediv__(self, other):
 247         return self.value / self._extract_value(other)
 248
 249     def __rtruediv__(self, other):
 250         return self._extract_value(other) / self.value
 251
 252     def __pow__(self, exponent):
 253         return self.value ** self._extract_value(exponent)
 254
 255     def __rpow__(self, base):
 256         return self._extract_value(base) ** self.value
 257
 258     def __iadd__(self, other):
 259         self.value = self + other
 260         return self
 261
 262     def __isub__(self, other):
 263         self.value = self - other
 264         return self
 265
 266     def __imul__(self, other):
 267         self.value = self * other
 268         return self
 269
 270     def __itruediv__(self, other):
 271         self.value = self / other
 272         return self
 273
 274     def __ifloordiv__(self, other):
 275         self.value = self // other
 276         return self
 277
 278     def __imod__(self, other):
 279         self.value = self % other
 280         return self
 281
 282     def __ipow__(self, other):
 283         self.value = self ** other
 284         return self
 285
 286
 287 class _IntegralValue(_NumericValue, numbers.Integral):
 288     def __lshift__(self, other):
 289         return self.value << self._extract_value(other)
 290
 291     def __rlshift__(self, other):
 292         return self._extract_value(other) << self.value
 293
 294     def __rshift__(self, other):
 295         return self.value >> self._extract_value(other)
 296
 297     def __rrshift__(self, other):
 298         return self._extract_value(other) >> self.value
 299
 300     def __and__(self, other):
 301         return self.value & self._extract_value(other)
 302
 303     def __rand__(self, other):
 304         return self._extract_value(other) & self.value
 305
 306     def __xor__(self, other):
 307         return self.value ^ self._extract_value(other)
 308
 309     def __rxor__(self, other):
 310         return self._extract_value(other) ^ self.value
 311
 312     def __or__(self, other):
 313         return self.value | self._extract_value(other)
 314
 315     def __ror__(self, other):
 316         return self._extract_value(other) | self.value
 317
 318     def __invert__(self):
 319         return ~self.value
 320
 321     def __ilshift__(self, other):
 322         self.value = self << other
 323         return self
 324
 325     def __irshift__(self, other):
 326         self.value = self >> other
 327         return self
 328
 329     def __iand__(self, other):
 330         self.value = self & other
 331         return self
 332
 333     def __ixor__(self, other):
 334         self.value = self ^ other
 335         return self
 336
 337     def __ior__(self, other):
 338         self.value = self | other
 339         return self
 340
 341
 342 class _RealValue(_NumericValue, numbers.Real):
 343     pass
 344
 345
 346 class BoolValue(_Value, _BasicCopy):
 347     _NAME = 'Boolean'
 348
 349     def __init__(self, value=None):
 350         if value is None:
 351             ptr = native_bt.value_bool_create()
 352         else:
 353             ptr = native_bt.value_bool_create_init(self._value_to_bool(value))
 354
 355         self._check_create_status(ptr)
 356         super().__init__(ptr)
 357
 358     def _spec_eq(self, other):
 359         if isinstance(other, numbers.Number):
 360             return self.value == bool(other)
 361
 362     def __bool__(self):
 363         return self.value
 364
 365     def __str__(self):
 366         return str(self.value)
 367
 368     def _value_to_bool(self, value):
 369         if isinstance(value, BoolValue):
 370             value = value.value
 371
 372         if not isinstance(value, bool):
 373             raise TypeError("'{}' object is not a 'bool' or 'BoolValue' object".format(value.__class__))
 374
 375         return value
 376
 377     @property
 378     def value(self):
 379         status, value = native_bt.value_bool_get(self._ptr)
 380         self._handle_status(status)
 381         return value
 382
 383     @value.setter
 384     def value(self, value):
 385         status = native_bt.value_bool_set(self._ptr, self._value_to_bool(value))
 386         self._handle_status(status)
 387
 388
 389 class IntegerValue(_IntegralValue):
 390     _NAME = 'Integer'
 391
 392     def __init__(self, value=None):
 393         if value is None:
 394             ptr = native_bt.value_integer_create()
 395         else:
 396             ptr = native_bt.value_integer_create_init(self._value_to_int(value))
 397
 398         self._check_create_status(ptr)
 399         super().__init__(ptr)
 400
 401     def _value_to_int(self, value):
 402         if not isinstance(value, numbers.Real):
 403             raise TypeError('expecting a number object')
 404
 405         value = int(value)
 406         utils._check_int64(value)
 407         return value
 408
 409     @property
 410     def value(self):
 411         status, value = native_bt.value_integer_get(self._ptr)
 412         self._handle_status(status)
 413         return value
 414
 415     @value.setter
 416     def value(self, value):
 417         status = native_bt.value_integer_set(self._ptr, self._value_to_int(value))
 418         self._handle_status(status)
 419
 420
 421 class FloatValue(_RealValue):
 422     _NAME = 'Floating point number'
 423
 424     def __init__(self, value=None):
 425         if value is None:
 426             ptr = native_bt.value_float_create()
 427         else:
 428             value = self._value_to_float(value)
 429             ptr = native_bt.value_float_create_init(value)
 430
 431         self._check_create_status(ptr)
 432         super().__init__(ptr)
 433
 434     def _value_to_float(self, value):
 435         if not isinstance(value, numbers.Real):
 436             raise TypeError("expecting a real number object")
 437
 438         return float(value)
 439
 440     @property
 441     def value(self):
 442         status, value = native_bt.value_float_get(self._ptr)
 443         self._handle_status(status)
 444         return value
 445
 446     @value.setter
 447     def value(self, value):
 448         value = self._value_to_float(value)
 449         status = native_bt.value_float_set(self._ptr, value)
 450         self._handle_status(status)
 451
 452
 453 @functools.total_ordering
 454 class StringValue(_BasicCopy, collections.abc.Sequence, _Value):
 455     _NAME = 'String'
 456
 457     def __init__(self, value=None):
 458         if value is None:
 459             ptr = native_bt.value_string_create()
 460         else:
 461             ptr = native_bt.value_string_create_init(self._value_to_str(value))
 462
 463         self._check_create_status(ptr)
 464         super().__init__(ptr)
 465
 466     def _value_to_str(self, value):
 467         if isinstance(value, self.__class__):
 468             value = value.value
 469
 470         utils._check_str(value)
 471         return value
 472
 473     @property
 474     def value(self):
 475         status, value = native_bt.value_string_get(self._ptr)
 476         self._handle_status(status)
 477         return value
 478
 479     @value.setter
 480     def value(self, value):
 481         status = native_bt.value_string_set(self._ptr, self._value_to_str(value))
 482         self._handle_status(status)
 483
 484     def _spec_eq(self, other):
 485         try:
 486             return self.value == self._value_to_str(other)
 487         except:
 488             return
 489
 490     def __le__(self, other):
 491         return self.value <= self._value_to_str(other)
 492
 493     def __lt__(self, other):
 494         return self.value < self._value_to_str(other)
 495
 496     def __bool__(self):
 497         return bool(self.value)
 498
 499     def __str__(self):
 500         return self.value
 501
 502     def __getitem__(self, index):
 503         return self.value[index]
 504
 505     def __len__(self):
 506         return len(self.value)
 507
 508     def __iadd__(self, value):
 509         curvalue = self.value
 510         curvalue += self._value_to_str(value)
 511         self.value = curvalue
 512         return self
 513
 514
 515 class _Container:
 516     def __bool__(self):
 517         return len(self) != 0
 518
 519     def __copy__(self):
 520         return self.__class__(self)
 521
 522     def __deepcopy__(self, memo):
 523         ptr = native_bt.value_copy(self._ptr)
 524
 525         if ptr is None:
 526             fmt = 'unexpected error: cannot deep-copy {} value object'
 527             raise RuntimeError(fmt.format(self._NAME))
 528
 529         copy = self.__class__._create_from_ptr(ptr)
 530         memo[id(self)] = copy
 531         return copy
 532
 533     def __delitem__(self, index):
 534         raise NotImplementedError
 535
 536
 537 class ArrayValue(_Container, collections.abc.MutableSequence, _Value):
 538     _NAME = 'Array'
 539
 540     def __init__(self, value=None):
 541         ptr = native_bt.value_array_create()
 542         self._check_create_status(ptr)
 543         super().__init__(ptr)
 544
 545         # Python will raise a TypeError if there's anything wrong with
 546         # the iterable protocol.
 547         if value is not None:
 548             for elem in value:
 549                 self.append(elem)
 550
 551     def _spec_eq(self, other):
 552         try:
 553             if len(self) != len(other):
 554                 # early mismatch
 555                 return False
 556
 557             for self_elem, other_elem in zip(self, other):
 558                 if self_elem != other_elem:
 559                     return False
 560
 561             return True
 562         except:
 563             return
 564
 565     def __len__(self):
 566         size = native_bt.value_array_size(self._ptr)
 567         self._handle_status(size)
 568         return size
 569
 570     def _check_index(self, index):
 571         # TODO: support slices also
 572         if not isinstance(index, numbers.Integral):
 573             raise TypeError("'{}' object is not an integral number object: invalid index".format(index.__class__.__name__))
 574
 575         index = int(index)
 576
 577         if index < 0 or index >= len(self):
 578             raise IndexError('array value object index is out of range')
 579
 580     def __getitem__(self, index):
 581         self._check_index(index)
 582         ptr = native_bt.value_array_get(self._ptr, index)
 583
 584         if ptr is None:
 585             raise RuntimeError('unexpected error: cannot get array value object element')
 586
 587         return _create_from_ptr(ptr)
 588
 589     def __setitem__(self, index, value):
 590         self._check_index(index)
 591         value = create_value(value)
 592
 593         if value is None:
 594             ptr = native_bt.value_null
 595         else:
 596             ptr = value._ptr
 597
 598         status = native_bt.value_array_set(self._ptr, index, ptr)
 599         self._handle_status(status)
 600
 601     def append(self, value):
 602         value = create_value(value)
 603
 604         if value is None:
 605             ptr = native_bt.value_null
 606         else:
 607             ptr = value._ptr
 608
 609         status = native_bt.value_array_append(self._ptr, ptr)
 610         self._handle_status(status)
 611
 612     def __iadd__(self, iterable):
 613         # Python will raise a TypeError if there's anything wrong with
 614         # the iterable protocol.
 615         for elem in iterable:
 616             self.append(elem)
 617
 618         return self
 619
 620     def __str__(self):
 621         strings = []
 622
 623         for elem in self:
 624             if isinstance(elem, StringValue):
 625                 strings.append(repr(elem.value))
 626             else:
 627                 strings.append(str(elem))
 628
 629         return '[{}]'.format(', '.join(strings))
 630
 631     def insert(self, value):
 632         raise NotImplementedError
 633
 634
 635 class _MapValueKeyIterator(collections.abc.Iterator):
 636     def __init__(self, map_obj):
 637         self._map_obj = map_obj
 638         self._at = 0
 639         keys_ptr = native_bt.value_map_get_keys_private(map_obj._ptr)
 640
 641         if keys_ptr is None:
 642             raise RuntimeError('unexpected error: cannot get map value object keys')
 643
 644         self._keys = _create_from_ptr(keys_ptr)
 645
 646     def __next__(self):
 647         if self._at == len(self._map_obj):
 648             raise StopIteration
 649
 650         key = self._keys[self._at]
 651         self._at += 1
 652         return str(key)
 653
 654
 655 class MapValue(_Container, collections.abc.MutableMapping, _Value):
 656     _NAME = 'Map'
 657
 658     def __init__(self, value=None):
 659         ptr = native_bt.value_map_create()
 660         self._check_create_status(ptr)
 661         super().__init__(ptr)
 662
 663         # Python will raise a TypeError if there's anything wrong with
 664         # the iterable/mapping protocol.
 665         if value is not None:
 666             for key, elem in value.items():
 667                 self[key] = elem
 668
 669     def __eq__(self, other):
 670         return _Value.__eq__(self, other)
 671
 672     def __ne__(self, other):
 673         return _Value.__ne__(self, other)
 674
 675     def _spec_eq(self, other):
 676         try:
 677             if len(self) != len(other):
 678                 # early mismatch
 679                 return False
 680
 681             for self_key in self:
 682                 if self_key not in other:
 683                     return False
 684
 685                 self_value = self[self_key]
 686                 other_value = other[self_key]
 687
 688                 if self_value != other_value:
 689                     return False
 690
 691             return True
 692         except:
 693             return
 694
 695     def __len__(self):
 696         size = native_bt.value_map_size(self._ptr)
 697         self._handle_status(size)
 698         return size
 699
 700     def __contains__(self, key):
 701         self._check_key_type(key)
 702         return native_bt.value_map_has_key(self._ptr, key)
 703
 704     def _check_key_type(self, key):
 705         utils._check_str(key)
 706
 707     def _check_key(self, key):
 708         if key not in self:
 709             raise KeyError(key)
 710
 711     def __getitem__(self, key):
 712         self._check_key(key)
 713         ptr = native_bt.value_map_get(self._ptr, key)
 714
 715         if ptr is None:
 716             raise RuntimeError('unexpected error: cannot get map value object element')
 717
 718         return _create_from_ptr(ptr)
 719
 720     def __iter__(self):
 721         return _MapValueKeyIterator(self)
 722
 723     def __setitem__(self, key, value):
 724         self._check_key_type(key)
 725         value = create_value(value)
 726
 727         if value is None:
 728             ptr = native_bt.value_null
 729         else:
 730             ptr = value._ptr
 731
 732         status = native_bt.value_map_insert(self._ptr, key, ptr)
 733         self._handle_status(status)
 734
 735     def __str__(self):
 736         strings = []
 737
 738         for key, elem in self.items():
 739             if isinstance(elem, StringValue):
 740                 value = repr(elem.value)
 741             else:
 742                 value = str(elem)
 743
 744             strings.append('{}: {}'.format(repr(key), value))
 745
 746         return '{{{}}}'.format(', '.join(strings))
 747
 748
 749 _TYPE_TO_OBJ = {
 750     native_bt.VALUE_TYPE_BOOL: BoolValue,
 751     native_bt.VALUE_TYPE_INTEGER: IntegerValue,
 752     native_bt.VALUE_TYPE_FLOAT: FloatValue,
 753     native_bt.VALUE_TYPE_STRING: StringValue,
 754     native_bt.VALUE_TYPE_ARRAY: ArrayValue,
 755     native_bt.VALUE_TYPE_MAP: MapValue,
 756 }