371 lines
13 KiB
Python
371 lines
13 KiB
Python
from __future__ import annotations
|
|
|
|
import errno
|
|
import json
|
|
import os
|
|
import types
|
|
import typing as t
|
|
|
|
from werkzeug.utils import import_string
|
|
|
|
if t.TYPE_CHECKING:
|
|
import typing_extensions as te
|
|
|
|
from .sansio.app import App
|
|
|
|
|
|
T = t.TypeVar("T")
|
|
|
|
|
|
class ConfigAttribute(t.Generic[T]):
|
|
"""Makes an attribute forward to the config"""
|
|
|
|
def __init__(
|
|
self, name: str, get_converter: t.Callable[[t.Any], T] | None = None
|
|
) -> None:
|
|
self.__name__ = name
|
|
self.get_converter = get_converter
|
|
|
|
@t.overload
|
|
def __get__(self, obj: None, owner: None) -> te.Self: ...
|
|
|
|
@t.overload
|
|
def __get__(self, obj: App, owner: type[App]) -> T: ...
|
|
|
|
def __get__(self, obj: App | None, owner: type[App] | None = None) -> T | te.Self:
|
|
if obj is None:
|
|
return self
|
|
|
|
rv = obj.config[self.__name__]
|
|
|
|
if self.get_converter is not None:
|
|
rv = self.get_converter(rv)
|
|
|
|
return rv # type: ignore[no-any-return]
|
|
|
|
def __set__(self, obj: App, value: t.Any) -> None:
|
|
obj.config[self.__name__] = value
|
|
|
|
|
|
class Config(dict): # type: ignore[type-arg]
|
|
"""Works exactly like a dict but provides ways to fill it from files
|
|
or special dictionaries. There are two common patterns to populate the
|
|
config.
|
|
|
|
Either you can fill the config from a config file::
|
|
|
|
app.config.from_pyfile('yourconfig.cfg')
|
|
|
|
Or alternatively you can define the configuration options in the
|
|
module that calls :meth:`from_object` or provide an import path to
|
|
a module that should be loaded. It is also possible to tell it to
|
|
use the same module and with that provide the configuration values
|
|
just before the call::
|
|
|
|
DEBUG = True
|
|
SECRET_KEY = 'development key'
|
|
app.config.from_object(__name__)
|
|
|
|
In both cases (loading from any Python file or loading from modules),
|
|
only uppercase keys are added to the config. This makes it possible to use
|
|
lowercase values in the config file for temporary values that are not added
|
|
to the config or to define the config keys in the same file that implements
|
|
the application.
|
|
|
|
Probably the most interesting way to load configurations is from an
|
|
environment variable pointing to a file::
|
|
|
|
app.config.from_envvar('YOURAPPLICATION_SETTINGS')
|
|
|
|
In this case before launching the application you have to set this
|
|
environment variable to the file you want to use. On Linux and OS X
|
|
use the export statement::
|
|
|
|
export YOURAPPLICATION_SETTINGS='/path/to/config/file'
|
|
|
|
On windows use `set` instead.
|
|
|
|
:param root_path: path to which files are read relative from. When the
|
|
config object is created by the application, this is
|
|
the application's :attr:`~flask.Flask.root_path`.
|
|
:param defaults: an optional dictionary of default values
|
|
"""
|
|
|
|
def __init__(
|
|
self,
|
|
root_path: str | os.PathLike[str],
|
|
defaults: dict[str, t.Any] | None = None,
|
|
) -> None:
|
|
super().__init__(defaults or {})
|
|
self.root_path = root_path
|
|
|
|
def from_envvar(self, variable_name: str, silent: bool = False) -> bool:
|
|
"""Loads a configuration from an environment variable pointing to
|
|
a configuration file. This is basically just a shortcut with nicer
|
|
error messages for this line of code::
|
|
|
|
app.config.from_pyfile(os.environ['YOURAPPLICATION_SETTINGS'])
|
|
|
|
:param variable_name: name of the environment variable
|
|
:param silent: set to ``True`` if you want silent failure for missing
|
|
files.
|
|
:return: ``True`` if the file was loaded successfully.
|
|
"""
|
|
rv = os.environ.get(variable_name)
|
|
if not rv:
|
|
if silent:
|
|
return False
|
|
raise RuntimeError(
|
|
f"The environment variable {variable_name!r} is not set"
|
|
" and as such configuration could not be loaded. Set"
|
|
" this variable and make it point to a configuration"
|
|
" file"
|
|
)
|
|
return self.from_pyfile(rv, silent=silent)
|
|
|
|
def from_prefixed_env(
|
|
self, prefix: str = "FLASK", *, loads: t.Callable[[str], t.Any] = json.loads
|
|
) -> bool:
|
|
"""Load any environment variables that start with ``FLASK_``,
|
|
dropping the prefix from the env key for the config key. Values
|
|
are passed through a loading function to attempt to convert them
|
|
to more specific types than strings.
|
|
|
|
Keys are loaded in :func:`sorted` order.
|
|
|
|
The default loading function attempts to parse values as any
|
|
valid JSON type, including dicts and lists.
|
|
|
|
Specific items in nested dicts can be set by separating the
|
|
keys with double underscores (``__``). If an intermediate key
|
|
doesn't exist, it will be initialized to an empty dict.
|
|
|
|
:param prefix: Load env vars that start with this prefix,
|
|
separated with an underscore (``_``).
|
|
:param loads: Pass each string value to this function and use
|
|
the returned value as the config value. If any error is
|
|
raised it is ignored and the value remains a string. The
|
|
default is :func:`json.loads`.
|
|
|
|
.. versionadded:: 2.1
|
|
"""
|
|
prefix = f"{prefix}_"
|
|
len_prefix = len(prefix)
|
|
|
|
for key in sorted(os.environ):
|
|
if not key.startswith(prefix):
|
|
continue
|
|
|
|
value = os.environ[key]
|
|
|
|
try:
|
|
value = loads(value)
|
|
except Exception:
|
|
# Keep the value as a string if loading failed.
|
|
pass
|
|
|
|
# Change to key.removeprefix(prefix) on Python >= 3.9.
|
|
key = key[len_prefix:]
|
|
|
|
if "__" not in key:
|
|
# A non-nested key, set directly.
|
|
self[key] = value
|
|
continue
|
|
|
|
# Traverse nested dictionaries with keys separated by "__".
|
|
current = self
|
|
*parts, tail = key.split("__")
|
|
|
|
for part in parts:
|
|
# If an intermediate dict does not exist, create it.
|
|
if part not in current:
|
|
current[part] = {}
|
|
|
|
current = current[part]
|
|
|
|
current[tail] = value
|
|
|
|
return True
|
|
|
|
def from_pyfile(
|
|
self, filename: str | os.PathLike[str], silent: bool = False
|
|
) -> bool:
|
|
"""Updates the values in the config from a Python file. This function
|
|
behaves as if the file was imported as module with the
|
|
:meth:`from_object` function.
|
|
|
|
:param filename: the filename of the config. This can either be an
|
|
absolute filename or a filename relative to the
|
|
root path.
|
|
:param silent: set to ``True`` if you want silent failure for missing
|
|
files.
|
|
:return: ``True`` if the file was loaded successfully.
|
|
|
|
.. versionadded:: 0.7
|
|
`silent` parameter.
|
|
"""
|
|
filename = os.path.join(self.root_path, filename)
|
|
d = types.ModuleType("config")
|
|
d.__file__ = filename
|
|
try:
|
|
with open(filename, mode="rb") as config_file:
|
|
exec(compile(config_file.read(), filename, "exec"), d.__dict__)
|
|
except OSError as e:
|
|
if silent and e.errno in (errno.ENOENT, errno.EISDIR, errno.ENOTDIR):
|
|
return False
|
|
e.strerror = f"Unable to load configuration file ({e.strerror})"
|
|
raise
|
|
self.from_object(d)
|
|
return True
|
|
|
|
def from_object(self, obj: object | str) -> None:
|
|
"""Updates the values from the given object. An object can be of one
|
|
of the following two types:
|
|
|
|
- a string: in this case the object with that name will be imported
|
|
- an actual object reference: that object is used directly
|
|
|
|
Objects are usually either modules or classes. :meth:`from_object`
|
|
loads only the uppercase attributes of the module/class. A ``dict``
|
|
object will not work with :meth:`from_object` because the keys of a
|
|
``dict`` are not attributes of the ``dict`` class.
|
|
|
|
Example of module-based configuration::
|
|
|
|
app.config.from_object('yourapplication.default_config')
|
|
from yourapplication import default_config
|
|
app.config.from_object(default_config)
|
|
|
|
Nothing is done to the object before loading. If the object is a
|
|
class and has ``@property`` attributes, it needs to be
|
|
instantiated before being passed to this method.
|
|
|
|
You should not use this function to load the actual configuration but
|
|
rather configuration defaults. The actual config should be loaded
|
|
with :meth:`from_pyfile` and ideally from a location not within the
|
|
package because the package might be installed system wide.
|
|
|
|
See :ref:`config-dev-prod` for an example of class-based configuration
|
|
using :meth:`from_object`.
|
|
|
|
:param obj: an import name or object
|
|
"""
|
|
if isinstance(obj, str):
|
|
obj = import_string(obj)
|
|
for key in dir(obj):
|
|
if key.isupper():
|
|
self[key] = getattr(obj, key)
|
|
|
|
def from_file(
|
|
self,
|
|
filename: str | os.PathLike[str],
|
|
load: t.Callable[[t.IO[t.Any]], t.Mapping[str, t.Any]],
|
|
silent: bool = False,
|
|
text: bool = True,
|
|
) -> bool:
|
|
"""Update the values in the config from a file that is loaded
|
|
using the ``load`` parameter. The loaded data is passed to the
|
|
:meth:`from_mapping` method.
|
|
|
|
.. code-block:: python
|
|
|
|
import json
|
|
app.config.from_file("config.json", load=json.load)
|
|
|
|
import tomllib
|
|
app.config.from_file("config.toml", load=tomllib.load, text=False)
|
|
|
|
:param filename: The path to the data file. This can be an
|
|
absolute path or relative to the config root path.
|
|
:param load: A callable that takes a file handle and returns a
|
|
mapping of loaded data from the file.
|
|
:type load: ``Callable[[Reader], Mapping]`` where ``Reader``
|
|
implements a ``read`` method.
|
|
:param silent: Ignore the file if it doesn't exist.
|
|
:param text: Open the file in text or binary mode.
|
|
:return: ``True`` if the file was loaded successfully.
|
|
|
|
.. versionchanged:: 2.3
|
|
The ``text`` parameter was added.
|
|
|
|
.. versionadded:: 2.0
|
|
"""
|
|
filename = os.path.join(self.root_path, filename)
|
|
|
|
try:
|
|
with open(filename, "r" if text else "rb") as f:
|
|
obj = load(f)
|
|
except OSError as e:
|
|
if silent and e.errno in (errno.ENOENT, errno.EISDIR):
|
|
return False
|
|
|
|
e.strerror = f"Unable to load configuration file ({e.strerror})"
|
|
raise
|
|
|
|
return self.from_mapping(obj)
|
|
|
|
def from_mapping(
|
|
self, mapping: t.Mapping[str, t.Any] | None = None, **kwargs: t.Any
|
|
) -> bool:
|
|
"""Updates the config like :meth:`update` ignoring items with
|
|
non-upper keys.
|
|
|
|
:return: Always returns ``True``.
|
|
|
|
.. versionadded:: 0.11
|
|
"""
|
|
mappings: dict[str, t.Any] = {}
|
|
if mapping is not None:
|
|
mappings.update(mapping)
|
|
mappings.update(kwargs)
|
|
for key, value in mappings.items():
|
|
if key.isupper():
|
|
self[key] = value
|
|
return True
|
|
|
|
def get_namespace(
|
|
self, namespace: str, lowercase: bool = True, trim_namespace: bool = True
|
|
) -> dict[str, t.Any]:
|
|
"""Returns a dictionary containing a subset of configuration options
|
|
that match the specified namespace/prefix. Example usage::
|
|
|
|
app.config['IMAGE_STORE_TYPE'] = 'fs'
|
|
app.config['IMAGE_STORE_PATH'] = '/var/app/images'
|
|
app.config['IMAGE_STORE_BASE_URL'] = 'http://img.website.com'
|
|
image_store_config = app.config.get_namespace('IMAGE_STORE_')
|
|
|
|
The resulting dictionary `image_store_config` would look like::
|
|
|
|
{
|
|
'type': 'fs',
|
|
'path': '/var/app/images',
|
|
'base_url': 'http://img.website.com'
|
|
}
|
|
|
|
This is often useful when configuration options map directly to
|
|
keyword arguments in functions or class constructors.
|
|
|
|
:param namespace: a configuration namespace
|
|
:param lowercase: a flag indicating if the keys of the resulting
|
|
dictionary should be lowercase
|
|
:param trim_namespace: a flag indicating if the keys of the resulting
|
|
dictionary should not include the namespace
|
|
|
|
.. versionadded:: 0.11
|
|
"""
|
|
rv = {}
|
|
for k, v in self.items():
|
|
if not k.startswith(namespace):
|
|
continue
|
|
if trim_namespace:
|
|
key = k[len(namespace) :]
|
|
else:
|
|
key = k
|
|
if lowercase:
|
|
key = key.lower()
|
|
rv[key] = v
|
|
return rv
|
|
|
|
def __repr__(self) -> str:
|
|
return f"<{type(self).__name__} {dict.__repr__(self)}>"
|