Config

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.

Attributes

Attribute	Type	Description
root_path	`str	os.PathLike[str]`

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Constructor

Signature

def Config(
    root_path: str | os.PathLike[str],
    defaults: dict[str, t.Any]| None = None
) - > None

Parameters

Name	Type	Description
root_path	`str	os.PathLike[str]`
defaults	`dict[str, t.Any]	None` = None

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Methods

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from_envvar()

@classmethod
def from_envvar(
    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'])

Parameters

Name	Type	Description
variable_name	str	The name of the environment variable that contains the path to the configuration file
silent	bool = False	Set to True if you want silent failure for missing files.

Returns

Type	Description
bool	True if the file was loaded successfully.

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from_prefixed_env()

@classmethod
def from_prefixed_env(
    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.

Parameters

Name	Type	Description
prefix	str = "FLASK"	Load env vars that start with this prefix, separated with an underscore (_).
loads	t.Callable[[str], t.Any] = json.loads	Pass each string value to this function and use the returned value as the config value.

Returns

Type	Description
bool	Always returns True after processing matching environment variables

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from_pyfile()

@classmethod
def from_pyfile(
    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 from_object function.

Parameters

Name	Type	Description
filename	`str	os.PathLike[str]`
silent	bool = False	Set to True if you want silent failure for missing files.

Returns

Type	Description
bool	True if the file was loaded successfully.

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from_object()

@classmethod
def from_object(
    obj: object | str
)

Updates the values from the given object. Objects are usually either modules or classes. from_object loads only the uppercase attributes of the module/class.

Parameters

Name	Type	Description
obj	`object	str`

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from_file()

@classmethod
def from_file(
    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 from_mapping method.

Parameters

Name	Type	Description
filename	`str	os.PathLike[str]`
load	t.Callable[[t.IO[t.Any]], t.Mapping[str, t.Any]]	A callable that takes a file handle and returns a mapping of loaded data from the file.
silent	bool = False	Ignore the file if it doesn't exist.
text	bool = True	Open the file in text or binary mode.

Returns

Type	Description
bool	True if the file was loaded successfully.

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from_mapping()

@classmethod
def from_mapping(
    mapping: t.Mapping[str, t.Any]| None = None,
    kwargs: t.Any
) - > bool

Updates the config like update ignoring items with non-upper keys.

Parameters

Name	Type	Description
mapping	`t.Mapping[str, t.Any]	None` = None
kwargs	t.Any	Arbitrary keyword arguments to be used as configuration values

Returns

Type	Description
bool	Always returns True.

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get_namespace()

@classmethod
def get_namespace(
    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.

Parameters

Name	Type	Description
namespace	str	A configuration namespace string to filter keys by
lowercase	bool = True	A flag indicating if the keys of the resulting dictionary should be lowercase
trim_namespace	bool = True	A flag indicating if the keys of the resulting dictionary should not include the namespace

Returns

Type	Description
dict[str, t.Any]	A dictionary containing the filtered configuration keys, optionally lowercased and with the namespace prefix removed

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