flask.config.Config

class documentation

class Config(dict):

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 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.

Parameters
root_path	path to which files are read relative from. When the config object is created by the application, this is the application's `~flask.Flask.root_path`.
defaults	an optional dictionary of default values

Method	`__init__`	Undocumented
Method	`__repr__`	Undocumented
Method	`from_envvar`	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:
Method	`from_file`	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.
Method	`from_json`	Update the values in the config from a JSON file. The loaded data is passed to the `from_mapping` method.
Method	`from_mapping`	Updates the config like `update` ignoring items with non-upper keys. :return: Always returns `True`.
Method	`from_object`	Updates the values from the given object. An object can be of one of the following two types:
Method	`from_pyfile`	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.
Method	`get_namespace`	Returns a dictionary containing a subset of configuration options that match the specified namespace/prefix. Example usage:
Instance Variable	`root_path`	Undocumented

def __init__(self, root_path, defaults=None):

Undocumented

Parameters
root_path:`str`	Undocumented
defaults:`t.Optional[dict]`	Undocumented

def __repr__(self):

Undocumented

Returns
`str`	Undocumented

def from_envvar(self, variable_name, silent=False):

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
variable_name:`str`	name of the environment variable
silent:`bool`	set to `True` if you want silent failure for missing files.
Returns
`bool`	`True` if the file was loaded successfully.

def from_file(self, filename, load, silent=False):

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.

import toml
app.config.from_file("config.toml", load=toml.load)

New in version 2.0.

Parameters
filename:`str`	The path to the data file. This can be an absolute path or relative to the config root path.
load:`Callable[[Reader], Mapping]` where `Reader` implements a `read` method.	A callable that takes a file handle and returns a mapping of loaded data from the file.
silent:`bool`	Ignore the file if it doesn't exist.
Returns
`bool`	`True` if the file was loaded successfully.

def from_json(self, filename, silent=False):

Update the values in the config from a JSON file. The loaded data is passed to the from_mapping method.

Deprecated since version 2.0.0: Will be removed in Flask 2.1. Use from_file instead. This was removed early in 2.0.0, was added back in 2.0.1.

New in version 0.11.

Parameters
filename:`str`	The path to the JSON file. This can be an absolute path or relative to the config root path.
silent:`bool`	Ignore the file if it doesn't exist.
Returns
`bool`	`True` if the file was loaded successfully.

def from_mapping(self, mapping=None, **kwargs):

Updates the config like update ignoring items with non-upper keys. :return: Always returns True.

New in version 0.11.

Parameters
mapping:`t.Optional[t.Mapping[str, t.Any]]`	Undocumented
**kwargs:`t.Any`	Undocumented
Returns
`bool`	Undocumented

def from_object(self, obj):

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. from_object loads only the uppercase attributes of the module/class. A dict object will not work with 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 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 from_object.

Parameters
obj:`t.Union[object, str]`	an import name or object

def from_pyfile(self, filename, silent=False):

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.

New in version 0.7: silent parameter.

Parameters
filename:`str`	the filename of the config. This can either be an absolute filename or a filename relative to the root path.
silent:`bool`	set to `True` if you want silent failure for missing files.
Returns
`bool`	`True` if the file was loaded successfully.

def get_namespace(self, namespace, lowercase=True, trim_namespace=True):

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.

New in version 0.11.

Parameters
namespace:`str`	a configuration namespace
lowercase:`bool`	a flag indicating if the keys of the resulting dictionary should be lowercase
trim_namespace:`bool`	a flag indicating if the keys of the resulting dictionary should not include the namespace
Returns
`t.Dict[str, t.Any]`	Undocumented

root_path =

Undocumented