Files
Hotel-Booking/Backend/venv/lib/python3.12/site-packages/pydantic_settings/sources.py
2025-11-16 15:59:05 +02:00

650 lines
24 KiB
Python

from __future__ import annotations as _annotations
import json
import os
import warnings
from abc import ABC, abstractmethod
from collections import deque
from dataclasses import is_dataclass
from pathlib import Path
from typing import TYPE_CHECKING, Any, List, Mapping, Sequence, Tuple, Union, cast
from dotenv import dotenv_values
from pydantic import AliasChoices, AliasPath, BaseModel, Json
from pydantic._internal._typing_extra import origin_is_union
from pydantic._internal._utils import deep_update, lenient_issubclass
from pydantic.fields import FieldInfo
from typing_extensions import get_args, get_origin
from pydantic_settings.utils import path_type_label
if TYPE_CHECKING:
from pydantic_settings.main import BaseSettings
DotenvType = Union[Path, str, List[Union[Path, str]], Tuple[Union[Path, str], ...]]
# This is used as default value for `_env_file` in the `BaseSettings` class and
# `env_file` in `DotEnvSettingsSource` so the default can be distinguished from `None`.
# See the docstring of `BaseSettings` for more details.
ENV_FILE_SENTINEL: DotenvType = Path('')
class SettingsError(ValueError):
pass
class PydanticBaseSettingsSource(ABC):
"""
Abstract base class for settings sources, every settings source classes should inherit from it.
"""
def __init__(self, settings_cls: type[BaseSettings]):
self.settings_cls = settings_cls
self.config = settings_cls.model_config
@abstractmethod
def get_field_value(self, field: FieldInfo, field_name: str) -> tuple[Any, str, bool]:
"""
Gets the value, the key for model creation, and a flag to determine whether value is complex.
This is an abstract method that should be overridden in every settings source classes.
Args:
field: The field.
field_name: The field name.
Returns:
A tuple contains the key, value and a flag to determine whether value is complex.
"""
pass
def field_is_complex(self, field: FieldInfo) -> bool:
"""
Checks whether a field is complex, in which case it will attempt to be parsed as JSON.
Args:
field: The field.
Returns:
Whether the field is complex.
"""
return _annotation_is_complex(field.annotation, field.metadata)
def prepare_field_value(self, field_name: str, field: FieldInfo, value: Any, value_is_complex: bool) -> Any:
"""
Prepares the value of a field.
Args:
field_name: The field name.
field: The field.
value: The value of the field that has to be prepared.
value_is_complex: A flag to determine whether value is complex.
Returns:
The prepared value.
"""
if value is not None and (self.field_is_complex(field) or value_is_complex):
return self.decode_complex_value(field_name, field, value)
return value
def decode_complex_value(self, field_name: str, field: FieldInfo, value: Any) -> Any:
"""
Decode the value for a complex field
Args:
field_name: The field name.
field: The field.
value: The value of the field that has to be prepared.
Returns:
The decoded value for further preparation
"""
return json.loads(value)
@abstractmethod
def __call__(self) -> dict[str, Any]:
pass
class InitSettingsSource(PydanticBaseSettingsSource):
"""
Source class for loading values provided during settings class initialization.
"""
def __init__(self, settings_cls: type[BaseSettings], init_kwargs: dict[str, Any]):
self.init_kwargs = init_kwargs
super().__init__(settings_cls)
def get_field_value(self, field: FieldInfo, field_name: str) -> tuple[Any, str, bool]:
# Nothing to do here. Only implement the return statement to make mypy happy
return None, '', False
def __call__(self) -> dict[str, Any]:
return self.init_kwargs
def __repr__(self) -> str:
return f'InitSettingsSource(init_kwargs={self.init_kwargs!r})'
class PydanticBaseEnvSettingsSource(PydanticBaseSettingsSource):
def __init__(
self, settings_cls: type[BaseSettings], case_sensitive: bool | None = None, env_prefix: str | None = None
) -> None:
super().__init__(settings_cls)
self.case_sensitive = case_sensitive if case_sensitive is not None else self.config.get('case_sensitive', False)
self.env_prefix = env_prefix if env_prefix is not None else self.config.get('env_prefix', '')
def _apply_case_sensitive(self, value: str) -> str:
return value.lower() if not self.case_sensitive else value
def _extract_field_info(self, field: FieldInfo, field_name: str) -> list[tuple[str, str, bool]]:
"""
Extracts field info. This info is used to get the value of field from environment variables.
It returns a list of tuples, each tuple contains:
* field_key: The key of field that has to be used in model creation.
* env_name: The environment variable name of the field.
* value_is_complex: A flag to determine whether the value from environment variable
is complex and has to be parsed.
Args:
field (FieldInfo): The field.
field_name (str): The field name.
Returns:
list[tuple[str, str, bool]]: List of tuples, each tuple contains field_key, env_name, and value_is_complex.
"""
field_info: list[tuple[str, str, bool]] = []
if isinstance(field.validation_alias, (AliasChoices, AliasPath)):
v_alias: str | list[str | int] | list[list[str | int]] | None = field.validation_alias.convert_to_aliases()
else:
v_alias = field.validation_alias
if v_alias:
if isinstance(v_alias, list): # AliasChoices, AliasPath
for alias in v_alias:
if isinstance(alias, str): # AliasPath
field_info.append((alias, self._apply_case_sensitive(alias), True if len(alias) > 1 else False))
elif isinstance(alias, list): # AliasChoices
first_arg = cast(str, alias[0]) # first item of an AliasChoices must be a str
field_info.append(
(first_arg, self._apply_case_sensitive(first_arg), True if len(alias) > 1 else False)
)
else: # string validation alias
field_info.append((v_alias, self._apply_case_sensitive(v_alias), False))
else:
field_info.append((field_name, self._apply_case_sensitive(self.env_prefix + field_name), False))
return field_info
def _replace_field_names_case_insensitively(self, field: FieldInfo, field_values: dict[str, Any]) -> dict[str, Any]:
"""
Replace field names in values dict by looking in models fields insensitively.
By having the following models:
```py
class SubSubSub(BaseModel):
VaL3: str
class SubSub(BaseModel):
Val2: str
SUB_sub_SuB: SubSubSub
class Sub(BaseModel):
VAL1: str
SUB_sub: SubSub
class Settings(BaseSettings):
nested: Sub
model_config = SettingsConfigDict(env_nested_delimiter='__')
```
Then:
_replace_field_names_case_insensitively(
field,
{"val1": "v1", "sub_SUB": {"VAL2": "v2", "sub_SUB_sUb": {"vAl3": "v3"}}}
)
Returns {'VAL1': 'v1', 'SUB_sub': {'Val2': 'v2', 'SUB_sub_SuB': {'VaL3': 'v3'}}}
"""
values: dict[str, Any] = {}
for name, value in field_values.items():
sub_model_field: FieldInfo | None = None
# This is here to make mypy happy
# Item "None" of "Optional[Type[Any]]" has no attribute "model_fields"
if not field.annotation or not hasattr(field.annotation, 'model_fields'):
values[name] = value
continue
# Find field in sub model by looking in fields case insensitively
for sub_model_field_name, f in field.annotation.model_fields.items():
if not f.validation_alias and sub_model_field_name.lower() == name.lower():
sub_model_field = f
break
if not sub_model_field:
values[name] = value
continue
if lenient_issubclass(sub_model_field.annotation, BaseModel) and isinstance(value, dict):
values[sub_model_field_name] = self._replace_field_names_case_insensitively(sub_model_field, value)
else:
values[sub_model_field_name] = value
return values
def __call__(self) -> dict[str, Any]:
data: dict[str, Any] = {}
for field_name, field in self.settings_cls.model_fields.items():
try:
field_value, field_key, value_is_complex = self.get_field_value(field, field_name)
except Exception as e:
raise SettingsError(
f'error getting value for field "{field_name}" from source "{self.__class__.__name__}"'
) from e
try:
field_value = self.prepare_field_value(field_name, field, field_value, value_is_complex)
except ValueError as e:
raise SettingsError(
f'error parsing value for field "{field_name}" from source "{self.__class__.__name__}"'
) from e
if field_value is not None:
if (
not self.case_sensitive
and lenient_issubclass(field.annotation, BaseModel)
and isinstance(field_value, dict)
):
data[field_key] = self._replace_field_names_case_insensitively(field, field_value)
else:
data[field_key] = field_value
return data
class SecretsSettingsSource(PydanticBaseEnvSettingsSource):
"""
Source class for loading settings values from secret files.
"""
def __init__(
self,
settings_cls: type[BaseSettings],
secrets_dir: str | Path | None = None,
case_sensitive: bool | None = None,
env_prefix: str | None = None,
) -> None:
super().__init__(settings_cls, case_sensitive, env_prefix)
self.secrets_dir = secrets_dir if secrets_dir is not None else self.config.get('secrets_dir')
def __call__(self) -> dict[str, Any]:
"""
Build fields from "secrets" files.
"""
secrets: dict[str, str | None] = {}
if self.secrets_dir is None:
return secrets
self.secrets_path = Path(self.secrets_dir).expanduser()
if not self.secrets_path.exists():
warnings.warn(f'directory "{self.secrets_path}" does not exist')
return secrets
if not self.secrets_path.is_dir():
raise SettingsError(f'secrets_dir must reference a directory, not a {path_type_label(self.secrets_path)}')
return super().__call__()
@classmethod
def find_case_path(cls, dir_path: Path, file_name: str, case_sensitive: bool) -> Path | None:
"""
Find a file within path's directory matching filename, optionally ignoring case.
Args:
dir_path: Directory path.
file_name: File name.
case_sensitive: Whether to search for file name case sensitively.
Returns:
Whether file path or `None` if file does not exist in directory.
"""
for f in dir_path.iterdir():
if f.name == file_name:
return f
elif not case_sensitive and f.name.lower() == file_name.lower():
return f
return None
def get_field_value(self, field: FieldInfo, field_name: str) -> tuple[Any, str, bool]:
"""
Gets the value for field from secret file and a flag to determine whether value is complex.
Args:
field: The field.
field_name: The field name.
Returns:
A tuple contains the key, value if the file exists otherwise `None`, and
a flag to determine whether value is complex.
"""
for field_key, env_name, value_is_complex in self._extract_field_info(field, field_name):
path = self.find_case_path(self.secrets_path, env_name, self.case_sensitive)
if not path:
# path does not exist, we currently don't return a warning for this
continue
if path.is_file():
return path.read_text().strip(), field_key, value_is_complex
else:
warnings.warn(
f'attempted to load secret file "{path}" but found a {path_type_label(path)} instead.',
stacklevel=4,
)
return None, field_key, value_is_complex
def __repr__(self) -> str:
return f'SecretsSettingsSource(secrets_dir={self.secrets_dir!r})'
class EnvSettingsSource(PydanticBaseEnvSettingsSource):
"""
Source class for loading settings values from environment variables.
"""
def __init__(
self,
settings_cls: type[BaseSettings],
case_sensitive: bool | None = None,
env_prefix: str | None = None,
env_nested_delimiter: str | None = None,
) -> None:
super().__init__(settings_cls, case_sensitive, env_prefix)
self.env_nested_delimiter = (
env_nested_delimiter if env_nested_delimiter is not None else self.config.get('env_nested_delimiter')
)
self.env_prefix_len = len(self.env_prefix)
self.env_vars = self._load_env_vars()
def _load_env_vars(self) -> Mapping[str, str | None]:
if self.case_sensitive:
return os.environ
return {k.lower(): v for k, v in os.environ.items()}
def get_field_value(self, field: FieldInfo, field_name: str) -> tuple[Any, str, bool]:
"""
Gets the value for field from environment variables and a flag to determine whether value is complex.
Args:
field: The field.
field_name: The field name.
Returns:
A tuple contains the key, value if the file exists otherwise `None`, and
a flag to determine whether value is complex.
"""
env_val: str | None = None
for field_key, env_name, value_is_complex in self._extract_field_info(field, field_name):
env_val = self.env_vars.get(env_name)
if env_val is not None:
break
return env_val, field_key, value_is_complex
def prepare_field_value(self, field_name: str, field: FieldInfo, value: Any, value_is_complex: bool) -> Any:
"""
Prepare value for the field.
* Extract value for nested field.
* Deserialize value to python object for complex field.
Args:
field: The field.
field_name: The field name.
Returns:
A tuple contains prepared value for the field.
Raises:
ValuesError: When There is an error in deserializing value for complex field.
"""
is_complex, allow_parse_failure = self._field_is_complex(field)
if is_complex or value_is_complex:
if value is None:
# field is complex but no value found so far, try explode_env_vars
env_val_built = self.explode_env_vars(field_name, field, self.env_vars)
if env_val_built:
return env_val_built
else:
# field is complex and there's a value, decode that as JSON, then add explode_env_vars
try:
value = self.decode_complex_value(field_name, field, value)
except ValueError as e:
if not allow_parse_failure:
raise e
if isinstance(value, dict):
return deep_update(value, self.explode_env_vars(field_name, field, self.env_vars))
else:
return value
elif value is not None:
# simplest case, field is not complex, we only need to add the value if it was found
return value
def _union_is_complex(self, annotation: type[Any] | None, metadata: list[Any]) -> bool:
return any(_annotation_is_complex(arg, metadata) for arg in get_args(annotation))
def _field_is_complex(self, field: FieldInfo) -> tuple[bool, bool]:
"""
Find out if a field is complex, and if so whether JSON errors should be ignored
"""
if self.field_is_complex(field):
allow_parse_failure = False
elif origin_is_union(get_origin(field.annotation)) and self._union_is_complex(field.annotation, field.metadata):
allow_parse_failure = True
else:
return False, False
return True, allow_parse_failure
@staticmethod
def next_field(field: FieldInfo | None, key: str) -> FieldInfo | None:
"""
Find the field in a sub model by key(env name)
By having the following models:
```py
class SubSubModel(BaseSettings):
dvals: Dict
class SubModel(BaseSettings):
vals: list[str]
sub_sub_model: SubSubModel
class Cfg(BaseSettings):
sub_model: SubModel
```
Then:
next_field(sub_model, 'vals') Returns the `vals` field of `SubModel` class
next_field(sub_model, 'sub_sub_model') Returns `sub_sub_model` field of `SubModel` class
Args:
field: The field.
key: The key (env name).
Returns:
Field if it finds the next field otherwise `None`.
"""
if not field or origin_is_union(get_origin(field.annotation)):
# no support for Unions of complex BaseSettings fields
return None
elif field.annotation and hasattr(field.annotation, 'model_fields') and field.annotation.model_fields.get(key):
return field.annotation.model_fields[key]
return None
def explode_env_vars(self, field_name: str, field: FieldInfo, env_vars: Mapping[str, str | None]) -> dict[str, Any]:
"""
Process env_vars and extract the values of keys containing env_nested_delimiter into nested dictionaries.
This is applied to a single field, hence filtering by env_var prefix.
Args:
field_name: The field name.
field: The field.
env_vars: Environment variables.
Returns:
A dictionaty contains extracted values from nested env values.
"""
prefixes = [
f'{env_name}{self.env_nested_delimiter}' for _, env_name, _ in self._extract_field_info(field, field_name)
]
result: dict[str, Any] = {}
for env_name, env_val in env_vars.items():
if not any(env_name.startswith(prefix) for prefix in prefixes):
continue
# we remove the prefix before splitting in case the prefix has characters in common with the delimiter
env_name_without_prefix = env_name[self.env_prefix_len :]
_, *keys, last_key = env_name_without_prefix.split(self.env_nested_delimiter)
env_var = result
target_field: FieldInfo | None = field
for key in keys:
target_field = self.next_field(target_field, key)
env_var = env_var.setdefault(key, {})
# get proper field with last_key
target_field = self.next_field(target_field, last_key)
# check if env_val maps to a complex field and if so, parse the env_val
if target_field and env_val:
is_complex, allow_json_failure = self._field_is_complex(target_field)
if is_complex:
try:
env_val = self.decode_complex_value(last_key, target_field, env_val)
except ValueError as e:
if not allow_json_failure:
raise e
env_var[last_key] = env_val
return result
def __repr__(self) -> str:
return (
f'EnvSettingsSource(env_nested_delimiter={self.env_nested_delimiter!r}, '
f'env_prefix_len={self.env_prefix_len!r})'
)
class DotEnvSettingsSource(EnvSettingsSource):
"""
Source class for loading settings values from env files.
"""
def __init__(
self,
settings_cls: type[BaseSettings],
env_file: DotenvType | None = ENV_FILE_SENTINEL,
env_file_encoding: str | None = None,
case_sensitive: bool | None = None,
env_prefix: str | None = None,
env_nested_delimiter: str | None = None,
) -> None:
self.env_file = env_file if env_file != ENV_FILE_SENTINEL else settings_cls.model_config.get('env_file')
self.env_file_encoding = (
env_file_encoding if env_file_encoding is not None else settings_cls.model_config.get('env_file_encoding')
)
super().__init__(settings_cls, case_sensitive, env_prefix, env_nested_delimiter)
def _load_env_vars(self) -> Mapping[str, str | None]:
return self._read_env_files(self.case_sensitive)
def _read_env_files(self, case_sensitive: bool) -> Mapping[str, str | None]:
env_files = self.env_file
if env_files is None:
return {}
if isinstance(env_files, (str, os.PathLike)):
env_files = [env_files]
dotenv_vars: dict[str, str | None] = {}
for env_file in env_files:
env_path = Path(env_file).expanduser()
if env_path.is_file():
dotenv_vars.update(
read_env_file(env_path, encoding=self.env_file_encoding, case_sensitive=case_sensitive)
)
return dotenv_vars
def __call__(self) -> dict[str, Any]:
data: dict[str, Any] = super().__call__()
data_lower_keys: list[str] = []
if not self.case_sensitive:
data_lower_keys = [x.lower() for x in data.keys()]
# As `extra` config is allowed in dotenv settings source, We have to
# update data with extra env variabels from dotenv file.
for env_name, env_value in self.env_vars.items():
if env_name.startswith(self.env_prefix) and env_value is not None:
env_name_without_prefix = env_name[self.env_prefix_len :]
first_key, *_ = env_name_without_prefix.split(self.env_nested_delimiter)
if (data_lower_keys and first_key not in data_lower_keys) or (
not data_lower_keys and first_key not in data
):
data[first_key] = env_value
return data
def __repr__(self) -> str:
return (
f'DotEnvSettingsSource(env_file={self.env_file!r}, env_file_encoding={self.env_file_encoding!r}, '
f'env_nested_delimiter={self.env_nested_delimiter!r}, env_prefix_len={self.env_prefix_len!r})'
)
def read_env_file(
file_path: Path, *, encoding: str | None = None, case_sensitive: bool = False
) -> Mapping[str, str | None]:
file_vars: dict[str, str | None] = dotenv_values(file_path, encoding=encoding or 'utf8')
if not case_sensitive:
return {k.lower(): v for k, v in file_vars.items()}
else:
return file_vars
def _annotation_is_complex(annotation: type[Any] | None, metadata: list[Any]) -> bool:
if any(isinstance(md, Json) for md in metadata): # type: ignore[misc]
return False
origin = get_origin(annotation)
return (
_annotation_is_complex_inner(annotation)
or _annotation_is_complex_inner(origin)
or hasattr(origin, '__pydantic_core_schema__')
or hasattr(origin, '__get_pydantic_core_schema__')
)
def _annotation_is_complex_inner(annotation: type[Any] | None) -> bool:
if lenient_issubclass(annotation, (str, bytes)):
return False
return lenient_issubclass(annotation, (BaseModel, Mapping, Sequence, tuple, set, frozenset, deque)) or is_dataclass(
annotation
)