File size: 42,048 Bytes
9c6594c |
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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 |
"""Configuration for Pydantic models."""
from __future__ import annotations as _annotations
import warnings
from re import Pattern
from typing import TYPE_CHECKING, Any, Callable, Literal, TypeVar, Union, cast, overload
from typing_extensions import TypeAlias, TypedDict, Unpack, deprecated
from ._migration import getattr_migration
from .aliases import AliasGenerator
from .errors import PydanticUserError
from .warnings import PydanticDeprecatedSince211
if TYPE_CHECKING:
from ._internal._generate_schema import GenerateSchema as _GenerateSchema
from .fields import ComputedFieldInfo, FieldInfo
__all__ = ('ConfigDict', 'with_config')
JsonValue: TypeAlias = Union[int, float, str, bool, None, list['JsonValue'], 'JsonDict']
JsonDict: TypeAlias = dict[str, JsonValue]
JsonEncoder = Callable[[Any], Any]
JsonSchemaExtraCallable: TypeAlias = Union[
Callable[[JsonDict], None],
Callable[[JsonDict, type[Any]], None],
]
ExtraValues = Literal['allow', 'ignore', 'forbid']
class ConfigDict(TypedDict, total=False):
"""A TypedDict for configuring Pydantic behaviour."""
title: str | None
"""The title for the generated JSON schema, defaults to the model's name"""
model_title_generator: Callable[[type], str] | None
"""A callable that takes a model class and returns the title for it. Defaults to `None`."""
field_title_generator: Callable[[str, FieldInfo | ComputedFieldInfo], str] | None
"""A callable that takes a field's name and info and returns title for it. Defaults to `None`."""
str_to_lower: bool
"""Whether to convert all characters to lowercase for str types. Defaults to `False`."""
str_to_upper: bool
"""Whether to convert all characters to uppercase for str types. Defaults to `False`."""
str_strip_whitespace: bool
"""Whether to strip leading and trailing whitespace for str types."""
str_min_length: int
"""The minimum length for str types. Defaults to `None`."""
str_max_length: int | None
"""The maximum length for str types. Defaults to `None`."""
extra: ExtraValues | None
'''
Whether to ignore, allow, or forbid extra data during model initialization. Defaults to `'ignore'`.
Three configuration values are available:
- `'ignore'`: Providing extra data is ignored (the default):
```python
from pydantic import BaseModel, ConfigDict
class User(BaseModel):
model_config = ConfigDict(extra='ignore') # (1)!
name: str
user = User(name='John Doe', age=20) # (2)!
print(user)
#> name='John Doe'
```
1. This is the default behaviour.
2. The `age` argument is ignored.
- `'forbid'`: Providing extra data is not permitted, and a [`ValidationError`][pydantic_core.ValidationError]
will be raised if this is the case:
```python
from pydantic import BaseModel, ConfigDict, ValidationError
class Model(BaseModel):
x: int
model_config = ConfigDict(extra='forbid')
try:
Model(x=1, y='a')
except ValidationError as exc:
print(exc)
"""
1 validation error for Model
y
Extra inputs are not permitted [type=extra_forbidden, input_value='a', input_type=str]
"""
```
- `'allow'`: Providing extra data is allowed and stored in the `__pydantic_extra__` dictionary attribute:
```python
from pydantic import BaseModel, ConfigDict
class Model(BaseModel):
x: int
model_config = ConfigDict(extra='allow')
m = Model(x=1, y='a')
assert m.__pydantic_extra__ == {'y': 'a'}
```
By default, no validation will be applied to these extra items, but you can set a type for the values by overriding
the type annotation for `__pydantic_extra__`:
```python
from pydantic import BaseModel, ConfigDict, Field, ValidationError
class Model(BaseModel):
__pydantic_extra__: dict[str, int] = Field(init=False) # (1)!
x: int
model_config = ConfigDict(extra='allow')
try:
Model(x=1, y='a')
except ValidationError as exc:
print(exc)
"""
1 validation error for Model
y
Input should be a valid integer, unable to parse string as an integer [type=int_parsing, input_value='a', input_type=str]
"""
m = Model(x=1, y='2')
assert m.x == 1
assert m.y == 2
assert m.model_dump() == {'x': 1, 'y': 2}
assert m.__pydantic_extra__ == {'y': 2}
```
1. The `= Field(init=False)` does not have any effect at runtime, but prevents the `__pydantic_extra__` field from
being included as a parameter to the model's `__init__` method by type checkers.
'''
frozen: bool
"""
Whether models are faux-immutable, i.e. whether `__setattr__` is allowed, and also generates
a `__hash__()` method for the model. This makes instances of the model potentially hashable if all the
attributes are hashable. Defaults to `False`.
Note:
On V1, the inverse of this setting was called `allow_mutation`, and was `True` by default.
"""
populate_by_name: bool
"""
Whether an aliased field may be populated by its name as given by the model
attribute, as well as the alias. Defaults to `False`.
!!! warning
`populate_by_name` usage is not recommended in v2.11+ and will be deprecated in v3.
Instead, you should use the [`validate_by_name`][pydantic.config.ConfigDict.validate_by_name] configuration setting.
When `validate_by_name=True` and `validate_by_alias=True`, this is strictly equivalent to the
previous behavior of `populate_by_name=True`.
In v2.11, we also introduced a [`validate_by_alias`][pydantic.config.ConfigDict.validate_by_alias] setting that introduces more fine grained
control for validation behavior.
Here's how you might go about using the new settings to achieve the same behavior:
```python
from pydantic import BaseModel, ConfigDict, Field
class Model(BaseModel):
model_config = ConfigDict(validate_by_name=True, validate_by_alias=True)
my_field: str = Field(alias='my_alias') # (1)!
m = Model(my_alias='foo') # (2)!
print(m)
#> my_field='foo'
m = Model(my_alias='foo') # (3)!
print(m)
#> my_field='foo'
```
1. The field `'my_field'` has an alias `'my_alias'`.
2. The model is populated by the alias `'my_alias'`.
3. The model is populated by the attribute name `'my_field'`.
"""
use_enum_values: bool
"""
Whether to populate models with the `value` property of enums, rather than the raw enum.
This may be useful if you want to serialize `model.model_dump()` later. Defaults to `False`.
!!! note
If you have an `Optional[Enum]` value that you set a default for, you need to use `validate_default=True`
for said Field to ensure that the `use_enum_values` flag takes effect on the default, as extracting an
enum's value occurs during validation, not serialization.
```python
from enum import Enum
from typing import Optional
from pydantic import BaseModel, ConfigDict, Field
class SomeEnum(Enum):
FOO = 'foo'
BAR = 'bar'
BAZ = 'baz'
class SomeModel(BaseModel):
model_config = ConfigDict(use_enum_values=True)
some_enum: SomeEnum
another_enum: Optional[SomeEnum] = Field(
default=SomeEnum.FOO, validate_default=True
)
model1 = SomeModel(some_enum=SomeEnum.BAR)
print(model1.model_dump())
#> {'some_enum': 'bar', 'another_enum': 'foo'}
model2 = SomeModel(some_enum=SomeEnum.BAR, another_enum=SomeEnum.BAZ)
print(model2.model_dump())
#> {'some_enum': 'bar', 'another_enum': 'baz'}
```
"""
validate_assignment: bool
"""
Whether to validate the data when the model is changed. Defaults to `False`.
The default behavior of Pydantic is to validate the data when the model is created.
In case the user changes the data after the model is created, the model is _not_ revalidated.
```python
from pydantic import BaseModel
class User(BaseModel):
name: str
user = User(name='John Doe') # (1)!
print(user)
#> name='John Doe'
user.name = 123 # (1)!
print(user)
#> name=123
```
1. The validation happens only when the model is created.
2. The validation does not happen when the data is changed.
In case you want to revalidate the model when the data is changed, you can use `validate_assignment=True`:
```python
from pydantic import BaseModel, ValidationError
class User(BaseModel, validate_assignment=True): # (1)!
name: str
user = User(name='John Doe') # (2)!
print(user)
#> name='John Doe'
try:
user.name = 123 # (3)!
except ValidationError as e:
print(e)
'''
1 validation error for User
name
Input should be a valid string [type=string_type, input_value=123, input_type=int]
'''
```
1. You can either use class keyword arguments, or `model_config` to set `validate_assignment=True`.
2. The validation happens when the model is created.
3. The validation _also_ happens when the data is changed.
"""
arbitrary_types_allowed: bool
"""
Whether arbitrary types are allowed for field types. Defaults to `False`.
```python
from pydantic import BaseModel, ConfigDict, ValidationError
# This is not a pydantic model, it's an arbitrary class
class Pet:
def __init__(self, name: str):
self.name = name
class Model(BaseModel):
model_config = ConfigDict(arbitrary_types_allowed=True)
pet: Pet
owner: str
pet = Pet(name='Hedwig')
# A simple check of instance type is used to validate the data
model = Model(owner='Harry', pet=pet)
print(model)
#> pet=<__main__.Pet object at 0x0123456789ab> owner='Harry'
print(model.pet)
#> <__main__.Pet object at 0x0123456789ab>
print(model.pet.name)
#> Hedwig
print(type(model.pet))
#> <class '__main__.Pet'>
try:
# If the value is not an instance of the type, it's invalid
Model(owner='Harry', pet='Hedwig')
except ValidationError as e:
print(e)
'''
1 validation error for Model
pet
Input should be an instance of Pet [type=is_instance_of, input_value='Hedwig', input_type=str]
'''
# Nothing in the instance of the arbitrary type is checked
# Here name probably should have been a str, but it's not validated
pet2 = Pet(name=42)
model2 = Model(owner='Harry', pet=pet2)
print(model2)
#> pet=<__main__.Pet object at 0x0123456789ab> owner='Harry'
print(model2.pet)
#> <__main__.Pet object at 0x0123456789ab>
print(model2.pet.name)
#> 42
print(type(model2.pet))
#> <class '__main__.Pet'>
```
"""
from_attributes: bool
"""
Whether to build models and look up discriminators of tagged unions using python object attributes.
"""
loc_by_alias: bool
"""Whether to use the actual key provided in the data (e.g. alias) for error `loc`s rather than the field's name. Defaults to `True`."""
alias_generator: Callable[[str], str] | AliasGenerator | None
"""
A callable that takes a field name and returns an alias for it
or an instance of [`AliasGenerator`][pydantic.aliases.AliasGenerator]. Defaults to `None`.
When using a callable, the alias generator is used for both validation and serialization.
If you want to use different alias generators for validation and serialization, you can use
[`AliasGenerator`][pydantic.aliases.AliasGenerator] instead.
If data source field names do not match your code style (e. g. CamelCase fields),
you can automatically generate aliases using `alias_generator`. Here's an example with
a basic callable:
```python
from pydantic import BaseModel, ConfigDict
from pydantic.alias_generators import to_pascal
class Voice(BaseModel):
model_config = ConfigDict(alias_generator=to_pascal)
name: str
language_code: str
voice = Voice(Name='Filiz', LanguageCode='tr-TR')
print(voice.language_code)
#> tr-TR
print(voice.model_dump(by_alias=True))
#> {'Name': 'Filiz', 'LanguageCode': 'tr-TR'}
```
If you want to use different alias generators for validation and serialization, you can use
[`AliasGenerator`][pydantic.aliases.AliasGenerator].
```python
from pydantic import AliasGenerator, BaseModel, ConfigDict
from pydantic.alias_generators import to_camel, to_pascal
class Athlete(BaseModel):
first_name: str
last_name: str
sport: str
model_config = ConfigDict(
alias_generator=AliasGenerator(
validation_alias=to_camel,
serialization_alias=to_pascal,
)
)
athlete = Athlete(firstName='John', lastName='Doe', sport='track')
print(athlete.model_dump(by_alias=True))
#> {'FirstName': 'John', 'LastName': 'Doe', 'Sport': 'track'}
```
Note:
Pydantic offers three built-in alias generators: [`to_pascal`][pydantic.alias_generators.to_pascal],
[`to_camel`][pydantic.alias_generators.to_camel], and [`to_snake`][pydantic.alias_generators.to_snake].
"""
ignored_types: tuple[type, ...]
"""A tuple of types that may occur as values of class attributes without annotations. This is
typically used for custom descriptors (classes that behave like `property`). If an attribute is set on a
class without an annotation and has a type that is not in this tuple (or otherwise recognized by
_pydantic_), an error will be raised. Defaults to `()`.
"""
allow_inf_nan: bool
"""Whether to allow infinity (`+inf` an `-inf`) and NaN values to float and decimal fields. Defaults to `True`."""
json_schema_extra: JsonDict | JsonSchemaExtraCallable | None
"""A dict or callable to provide extra JSON schema properties. Defaults to `None`."""
json_encoders: dict[type[object], JsonEncoder] | None
"""
A `dict` of custom JSON encoders for specific types. Defaults to `None`.
!!! warning "Deprecated"
This config option is a carryover from v1.
We originally planned to remove it in v2 but didn't have a 1:1 replacement so we are keeping it for now.
It is still deprecated and will likely be removed in the future.
"""
# new in V2
strict: bool
"""
_(new in V2)_ If `True`, strict validation is applied to all fields on the model.
By default, Pydantic attempts to coerce values to the correct type, when possible.
There are situations in which you may want to disable this behavior, and instead raise an error if a value's type
does not match the field's type annotation.
To configure strict mode for all fields on a model, you can set `strict=True` on the model.
```python
from pydantic import BaseModel, ConfigDict
class Model(BaseModel):
model_config = ConfigDict(strict=True)
name: str
age: int
```
See [Strict Mode](../concepts/strict_mode.md) for more details.
See the [Conversion Table](../concepts/conversion_table.md) for more details on how Pydantic converts data in both
strict and lax modes.
"""
# whether instances of models and dataclasses (including subclass instances) should re-validate, default 'never'
revalidate_instances: Literal['always', 'never', 'subclass-instances']
"""
When and how to revalidate models and dataclasses during validation. Accepts the string
values of `'never'`, `'always'` and `'subclass-instances'`. Defaults to `'never'`.
- `'never'` will not revalidate models and dataclasses during validation
- `'always'` will revalidate models and dataclasses during validation
- `'subclass-instances'` will revalidate models and dataclasses during validation if the instance is a
subclass of the model or dataclass
By default, model and dataclass instances are not revalidated during validation.
```python
from pydantic import BaseModel
class User(BaseModel, revalidate_instances='never'): # (1)!
hobbies: list[str]
class SubUser(User):
sins: list[str]
class Transaction(BaseModel):
user: User
my_user = User(hobbies=['reading'])
t = Transaction(user=my_user)
print(t)
#> user=User(hobbies=['reading'])
my_user.hobbies = [1] # (2)!
t = Transaction(user=my_user) # (3)!
print(t)
#> user=User(hobbies=[1])
my_sub_user = SubUser(hobbies=['scuba diving'], sins=['lying'])
t = Transaction(user=my_sub_user)
print(t)
#> user=SubUser(hobbies=['scuba diving'], sins=['lying'])
```
1. `revalidate_instances` is set to `'never'` by **default.
2. The assignment is not validated, unless you set `validate_assignment` to `True` in the model's config.
3. Since `revalidate_instances` is set to `never`, this is not revalidated.
If you want to revalidate instances during validation, you can set `revalidate_instances` to `'always'`
in the model's config.
```python
from pydantic import BaseModel, ValidationError
class User(BaseModel, revalidate_instances='always'): # (1)!
hobbies: list[str]
class SubUser(User):
sins: list[str]
class Transaction(BaseModel):
user: User
my_user = User(hobbies=['reading'])
t = Transaction(user=my_user)
print(t)
#> user=User(hobbies=['reading'])
my_user.hobbies = [1]
try:
t = Transaction(user=my_user) # (2)!
except ValidationError as e:
print(e)
'''
1 validation error for Transaction
user.hobbies.0
Input should be a valid string [type=string_type, input_value=1, input_type=int]
'''
my_sub_user = SubUser(hobbies=['scuba diving'], sins=['lying'])
t = Transaction(user=my_sub_user)
print(t) # (3)!
#> user=User(hobbies=['scuba diving'])
```
1. `revalidate_instances` is set to `'always'`.
2. The model is revalidated, since `revalidate_instances` is set to `'always'`.
3. Using `'never'` we would have gotten `user=SubUser(hobbies=['scuba diving'], sins=['lying'])`.
It's also possible to set `revalidate_instances` to `'subclass-instances'` to only revalidate instances
of subclasses of the model.
```python
from pydantic import BaseModel
class User(BaseModel, revalidate_instances='subclass-instances'): # (1)!
hobbies: list[str]
class SubUser(User):
sins: list[str]
class Transaction(BaseModel):
user: User
my_user = User(hobbies=['reading'])
t = Transaction(user=my_user)
print(t)
#> user=User(hobbies=['reading'])
my_user.hobbies = [1]
t = Transaction(user=my_user) # (2)!
print(t)
#> user=User(hobbies=[1])
my_sub_user = SubUser(hobbies=['scuba diving'], sins=['lying'])
t = Transaction(user=my_sub_user)
print(t) # (3)!
#> user=User(hobbies=['scuba diving'])
```
1. `revalidate_instances` is set to `'subclass-instances'`.
2. This is not revalidated, since `my_user` is not a subclass of `User`.
3. Using `'never'` we would have gotten `user=SubUser(hobbies=['scuba diving'], sins=['lying'])`.
"""
ser_json_timedelta: Literal['iso8601', 'float']
"""
The format of JSON serialized timedeltas. Accepts the string values of `'iso8601'` and
`'float'`. Defaults to `'iso8601'`.
- `'iso8601'` will serialize timedeltas to ISO 8601 durations.
- `'float'` will serialize timedeltas to the total number of seconds.
"""
ser_json_bytes: Literal['utf8', 'base64', 'hex']
"""
The encoding of JSON serialized bytes. Defaults to `'utf8'`.
Set equal to `val_json_bytes` to get back an equal value after serialization round trip.
- `'utf8'` will serialize bytes to UTF-8 strings.
- `'base64'` will serialize bytes to URL safe base64 strings.
- `'hex'` will serialize bytes to hexadecimal strings.
"""
val_json_bytes: Literal['utf8', 'base64', 'hex']
"""
The encoding of JSON serialized bytes to decode. Defaults to `'utf8'`.
Set equal to `ser_json_bytes` to get back an equal value after serialization round trip.
- `'utf8'` will deserialize UTF-8 strings to bytes.
- `'base64'` will deserialize URL safe base64 strings to bytes.
- `'hex'` will deserialize hexadecimal strings to bytes.
"""
ser_json_inf_nan: Literal['null', 'constants', 'strings']
"""
The encoding of JSON serialized infinity and NaN float values. Defaults to `'null'`.
- `'null'` will serialize infinity and NaN values as `null`.
- `'constants'` will serialize infinity and NaN values as `Infinity` and `NaN`.
- `'strings'` will serialize infinity as string `"Infinity"` and NaN as string `"NaN"`.
"""
# whether to validate default values during validation, default False
validate_default: bool
"""Whether to validate default values during validation. Defaults to `False`."""
validate_return: bool
"""Whether to validate the return value from call validators. Defaults to `False`."""
protected_namespaces: tuple[str | Pattern[str], ...]
"""
A `tuple` of strings and/or patterns that prevent models from having fields with names that conflict with them.
For strings, we match on a prefix basis. Ex, if 'dog' is in the protected namespace, 'dog_name' will be protected.
For patterns, we match on the entire field name. Ex, if `re.compile(r'^dog$')` is in the protected namespace, 'dog' will be protected, but 'dog_name' will not be.
Defaults to `('model_validate', 'model_dump',)`.
The reason we've selected these is to prevent collisions with other validation / dumping formats
in the future - ex, `model_validate_{some_newly_supported_format}`.
Before v2.10, Pydantic used `('model_',)` as the default value for this setting to
prevent collisions between model attributes and `BaseModel`'s own methods. This was changed
in v2.10 given feedback that this restriction was limiting in AI and data science contexts,
where it is common to have fields with names like `model_id`, `model_input`, `model_output`, etc.
For more details, see https://github.com/pydantic/pydantic/issues/10315.
```python
import warnings
from pydantic import BaseModel
warnings.filterwarnings('error') # Raise warnings as errors
try:
class Model(BaseModel):
model_dump_something: str
except UserWarning as e:
print(e)
'''
Field "model_dump_something" in Model has conflict with protected namespace "model_dump".
You may be able to resolve this warning by setting `model_config['protected_namespaces'] = ('model_validate',)`.
'''
```
You can customize this behavior using the `protected_namespaces` setting:
```python {test="skip"}
import re
import warnings
from pydantic import BaseModel, ConfigDict
with warnings.catch_warnings(record=True) as caught_warnings:
warnings.simplefilter('always') # Catch all warnings
class Model(BaseModel):
safe_field: str
also_protect_field: str
protect_this: str
model_config = ConfigDict(
protected_namespaces=(
'protect_me_',
'also_protect_',
re.compile('^protect_this$'),
)
)
for warning in caught_warnings:
print(f'{warning.message}')
'''
Field "also_protect_field" in Model has conflict with protected namespace "also_protect_".
You may be able to resolve this warning by setting `model_config['protected_namespaces'] = ('protect_me_', re.compile('^protect_this$'))`.
Field "protect_this" in Model has conflict with protected namespace "re.compile('^protect_this$')".
You may be able to resolve this warning by setting `model_config['protected_namespaces'] = ('protect_me_', 'also_protect_')`.
'''
```
While Pydantic will only emit a warning when an item is in a protected namespace but does not actually have a collision,
an error _is_ raised if there is an actual collision with an existing attribute:
```python
from pydantic import BaseModel, ConfigDict
try:
class Model(BaseModel):
model_validate: str
model_config = ConfigDict(protected_namespaces=('model_',))
except NameError as e:
print(e)
'''
Field "model_validate" conflicts with member <bound method BaseModel.model_validate of <class 'pydantic.main.BaseModel'>> of protected namespace "model_".
'''
```
"""
hide_input_in_errors: bool
"""
Whether to hide inputs when printing errors. Defaults to `False`.
Pydantic shows the input value and type when it raises `ValidationError` during the validation.
```python
from pydantic import BaseModel, ValidationError
class Model(BaseModel):
a: str
try:
Model(a=123)
except ValidationError as e:
print(e)
'''
1 validation error for Model
a
Input should be a valid string [type=string_type, input_value=123, input_type=int]
'''
```
You can hide the input value and type by setting the `hide_input_in_errors` config to `True`.
```python
from pydantic import BaseModel, ConfigDict, ValidationError
class Model(BaseModel):
a: str
model_config = ConfigDict(hide_input_in_errors=True)
try:
Model(a=123)
except ValidationError as e:
print(e)
'''
1 validation error for Model
a
Input should be a valid string [type=string_type]
'''
```
"""
defer_build: bool
"""
Whether to defer model validator and serializer construction until the first model validation. Defaults to False.
This can be useful to avoid the overhead of building models which are only
used nested within other models, or when you want to manually define type namespace via
[`Model.model_rebuild(_types_namespace=...)`][pydantic.BaseModel.model_rebuild].
Since v2.10, this setting also applies to pydantic dataclasses and TypeAdapter instances.
"""
plugin_settings: dict[str, object] | None
"""A `dict` of settings for plugins. Defaults to `None`."""
schema_generator: type[_GenerateSchema] | None
"""
!!! warning
`schema_generator` is deprecated in v2.10.
Prior to v2.10, this setting was advertised as highly subject to change.
It's possible that this interface may once again become public once the internal core schema generation
API is more stable, but that will likely come after significant performance improvements have been made.
"""
json_schema_serialization_defaults_required: bool
"""
Whether fields with default values should be marked as required in the serialization schema. Defaults to `False`.
This ensures that the serialization schema will reflect the fact a field with a default will always be present
when serializing the model, even though it is not required for validation.
However, there are scenarios where this may be undesirable β in particular, if you want to share the schema
between validation and serialization, and don't mind fields with defaults being marked as not required during
serialization. See [#7209](https://github.com/pydantic/pydantic/issues/7209) for more details.
```python
from pydantic import BaseModel, ConfigDict
class Model(BaseModel):
a: str = 'a'
model_config = ConfigDict(json_schema_serialization_defaults_required=True)
print(Model.model_json_schema(mode='validation'))
'''
{
'properties': {'a': {'default': 'a', 'title': 'A', 'type': 'string'}},
'title': 'Model',
'type': 'object',
}
'''
print(Model.model_json_schema(mode='serialization'))
'''
{
'properties': {'a': {'default': 'a', 'title': 'A', 'type': 'string'}},
'required': ['a'],
'title': 'Model',
'type': 'object',
}
'''
```
"""
json_schema_mode_override: Literal['validation', 'serialization', None]
"""
If not `None`, the specified mode will be used to generate the JSON schema regardless of what `mode` was passed to
the function call. Defaults to `None`.
This provides a way to force the JSON schema generation to reflect a specific mode, e.g., to always use the
validation schema.
It can be useful when using frameworks (such as FastAPI) that may generate different schemas for validation
and serialization that must both be referenced from the same schema; when this happens, we automatically append
`-Input` to the definition reference for the validation schema and `-Output` to the definition reference for the
serialization schema. By specifying a `json_schema_mode_override` though, this prevents the conflict between
the validation and serialization schemas (since both will use the specified schema), and so prevents the suffixes
from being added to the definition references.
```python
from pydantic import BaseModel, ConfigDict, Json
class Model(BaseModel):
a: Json[int] # requires a string to validate, but will dump an int
print(Model.model_json_schema(mode='serialization'))
'''
{
'properties': {'a': {'title': 'A', 'type': 'integer'}},
'required': ['a'],
'title': 'Model',
'type': 'object',
}
'''
class ForceInputModel(Model):
# the following ensures that even with mode='serialization', we
# will get the schema that would be generated for validation.
model_config = ConfigDict(json_schema_mode_override='validation')
print(ForceInputModel.model_json_schema(mode='serialization'))
'''
{
'properties': {
'a': {
'contentMediaType': 'application/json',
'contentSchema': {'type': 'integer'},
'title': 'A',
'type': 'string',
}
},
'required': ['a'],
'title': 'ForceInputModel',
'type': 'object',
}
'''
```
"""
coerce_numbers_to_str: bool
"""
If `True`, enables automatic coercion of any `Number` type to `str` in "lax" (non-strict) mode. Defaults to `False`.
Pydantic doesn't allow number types (`int`, `float`, `Decimal`) to be coerced as type `str` by default.
```python
from decimal import Decimal
from pydantic import BaseModel, ConfigDict, ValidationError
class Model(BaseModel):
value: str
try:
print(Model(value=42))
except ValidationError as e:
print(e)
'''
1 validation error for Model
value
Input should be a valid string [type=string_type, input_value=42, input_type=int]
'''
class Model(BaseModel):
model_config = ConfigDict(coerce_numbers_to_str=True)
value: str
repr(Model(value=42).value)
#> "42"
repr(Model(value=42.13).value)
#> "42.13"
repr(Model(value=Decimal('42.13')).value)
#> "42.13"
```
"""
regex_engine: Literal['rust-regex', 'python-re']
"""
The regex engine to be used for pattern validation.
Defaults to `'rust-regex'`.
- `rust-regex` uses the [`regex`](https://docs.rs/regex) Rust crate,
which is non-backtracking and therefore more DDoS resistant, but does not support all regex features.
- `python-re` use the [`re`](https://docs.python.org/3/library/re.html) module,
which supports all regex features, but may be slower.
!!! note
If you use a compiled regex pattern, the python-re engine will be used regardless of this setting.
This is so that flags such as `re.IGNORECASE` are respected.
```python
from pydantic import BaseModel, ConfigDict, Field, ValidationError
class Model(BaseModel):
model_config = ConfigDict(regex_engine='python-re')
value: str = Field(pattern=r'^abc(?=def)')
print(Model(value='abcdef').value)
#> abcdef
try:
print(Model(value='abxyzcdef'))
except ValidationError as e:
print(e)
'''
1 validation error for Model
value
String should match pattern '^abc(?=def)' [type=string_pattern_mismatch, input_value='abxyzcdef', input_type=str]
'''
```
"""
validation_error_cause: bool
"""
If `True`, Python exceptions that were part of a validation failure will be shown as an exception group as a cause. Can be useful for debugging. Defaults to `False`.
Note:
Python 3.10 and older don't support exception groups natively. <=3.10, backport must be installed: `pip install exceptiongroup`.
Note:
The structure of validation errors are likely to change in future Pydantic versions. Pydantic offers no guarantees about their structure. Should be used for visual traceback debugging only.
"""
use_attribute_docstrings: bool
'''
Whether docstrings of attributes (bare string literals immediately following the attribute declaration)
should be used for field descriptions. Defaults to `False`.
Available in Pydantic v2.7+.
```python
from pydantic import BaseModel, ConfigDict, Field
class Model(BaseModel):
model_config = ConfigDict(use_attribute_docstrings=True)
x: str
"""
Example of an attribute docstring
"""
y: int = Field(description="Description in Field")
"""
Description in Field overrides attribute docstring
"""
print(Model.model_fields["x"].description)
# > Example of an attribute docstring
print(Model.model_fields["y"].description)
# > Description in Field
```
This requires the source code of the class to be available at runtime.
!!! warning "Usage with `TypedDict` and stdlib dataclasses"
Due to current limitations, attribute docstrings detection may not work as expected when using
[`TypedDict`][typing.TypedDict] and stdlib dataclasses, in particular when:
- inheritance is being used.
- multiple classes have the same name in the same source file.
'''
cache_strings: bool | Literal['all', 'keys', 'none']
"""
Whether to cache strings to avoid constructing new Python objects. Defaults to True.
Enabling this setting should significantly improve validation performance while increasing memory usage slightly.
- `True` or `'all'` (the default): cache all strings
- `'keys'`: cache only dictionary keys
- `False` or `'none'`: no caching
!!! note
`True` or `'all'` is required to cache strings during general validation because
validators don't know if they're in a key or a value.
!!! tip
If repeated strings are rare, it's recommended to use `'keys'` or `'none'` to reduce memory usage,
as the performance difference is minimal if repeated strings are rare.
"""
validate_by_alias: bool
"""
Whether an aliased field may be populated by its alias. Defaults to `True`.
!!! note
In v2.11, `validate_by_alias` was introduced in conjunction with [`validate_by_name`][pydantic.ConfigDict.validate_by_name]
to empower users with more fine grained validation control. In <v2.11, disabling validation by alias was not possible.
Here's an example of disabling validation by alias:
```py
from pydantic import BaseModel, ConfigDict, Field
class Model(BaseModel):
model_config = ConfigDict(validate_by_name=True, validate_by_alias=False)
my_field: str = Field(validation_alias='my_alias') # (1)!
m = Model(my_field='foo') # (2)!
print(m)
#> my_field='foo'
```
1. The field `'my_field'` has an alias `'my_alias'`.
2. The model can only be populated by the attribute name `'my_field'`.
!!! warning
You cannot set both `validate_by_alias` and `validate_by_name` to `False`.
This would make it impossible to populate an attribute.
See [usage errors](../errors/usage_errors.md#validate-by-alias-and-name-false) for an example.
If you set `validate_by_alias` to `False`, under the hood, Pydantic dynamically sets
`validate_by_name` to `True` to ensure that validation can still occur.
"""
validate_by_name: bool
"""
Whether an aliased field may be populated by its name as given by the model
attribute. Defaults to `False`.
!!! note
In v2.0-v2.10, the `populate_by_name` configuration setting was used to specify
whether or not a field could be populated by its name **and** alias.
In v2.11, `validate_by_name` was introduced in conjunction with [`validate_by_alias`][pydantic.ConfigDict.validate_by_alias]
to empower users with more fine grained validation behavior control.
```python
from pydantic import BaseModel, ConfigDict, Field
class Model(BaseModel):
model_config = ConfigDict(validate_by_name=True, validate_by_alias=True)
my_field: str = Field(validation_alias='my_alias') # (1)!
m = Model(my_alias='foo') # (2)!
print(m)
#> my_field='foo'
m = Model(my_field='foo') # (3)!
print(m)
#> my_field='foo'
```
1. The field `'my_field'` has an alias `'my_alias'`.
2. The model is populated by the alias `'my_alias'`.
3. The model is populated by the attribute name `'my_field'`.
!!! warning
You cannot set both `validate_by_alias` and `validate_by_name` to `False`.
This would make it impossible to populate an attribute.
See [usage errors](../errors/usage_errors.md#validate-by-alias-and-name-false) for an example.
"""
serialize_by_alias: bool
"""
Whether an aliased field should be serialized by its alias. Defaults to `False`.
Note: In v2.11, `serialize_by_alias` was introduced to address the
[popular request](https://github.com/pydantic/pydantic/issues/8379)
for consistency with alias behavior for validation and serialization settings.
In v3, the default value is expected to change to `True` for consistency with the validation default.
```python
from pydantic import BaseModel, ConfigDict, Field
class Model(BaseModel):
model_config = ConfigDict(serialize_by_alias=True)
my_field: str = Field(serialization_alias='my_alias') # (1)!
m = Model(my_field='foo')
print(m.model_dump()) # (2)!
#> {'my_alias': 'foo'}
```
1. The field `'my_field'` has an alias `'my_alias'`.
2. The model is serialized using the alias `'my_alias'` for the `'my_field'` attribute.
"""
_TypeT = TypeVar('_TypeT', bound=type)
@overload
@deprecated('Passing `config` as a keyword argument is deprecated. Pass `config` as a positional argument instead.')
def with_config(*, config: ConfigDict) -> Callable[[_TypeT], _TypeT]: ...
@overload
def with_config(config: ConfigDict, /) -> Callable[[_TypeT], _TypeT]: ...
@overload
def with_config(**config: Unpack[ConfigDict]) -> Callable[[_TypeT], _TypeT]: ...
def with_config(config: ConfigDict | None = None, /, **kwargs: Any) -> Callable[[_TypeT], _TypeT]:
"""!!! abstract "Usage Documentation"
[Configuration with other types](../concepts/config.md#configuration-on-other-supported-types)
A convenience decorator to set a [Pydantic configuration](config.md) on a `TypedDict` or a `dataclass` from the standard library.
Although the configuration can be set using the `__pydantic_config__` attribute, it does not play well with type checkers,
especially with `TypedDict`.
!!! example "Usage"
```python
from typing_extensions import TypedDict
from pydantic import ConfigDict, TypeAdapter, with_config
@with_config(ConfigDict(str_to_lower=True))
class TD(TypedDict):
x: str
ta = TypeAdapter(TD)
print(ta.validate_python({'x': 'ABC'}))
#> {'x': 'abc'}
```
"""
if config is not None and kwargs:
raise ValueError('Cannot specify both `config` and keyword arguments')
if len(kwargs) == 1 and (kwargs_conf := kwargs.get('config')) is not None:
warnings.warn(
'Passing `config` as a keyword argument is deprecated. Pass `config` as a positional argument instead',
category=PydanticDeprecatedSince211,
stacklevel=2,
)
final_config = cast(ConfigDict, kwargs_conf)
else:
final_config = config if config is not None else cast(ConfigDict, kwargs)
def inner(class_: _TypeT, /) -> _TypeT:
# Ideally, we would check for `class_` to either be a `TypedDict` or a stdlib dataclass.
# However, the `@with_config` decorator can be applied *after* `@dataclass`. To avoid
# common mistakes, we at least check for `class_` to not be a Pydantic model.
from ._internal._utils import is_model_class
if is_model_class(class_):
raise PydanticUserError(
f'Cannot use `with_config` on {class_.__name__} as it is a Pydantic model',
code='with-config-on-model',
)
class_.__pydantic_config__ = final_config
return class_
return inner
__getattr__ = getattr_migration(__name__)
|