CasperSecurity
from __future__ import annotations
import logging
import sys
import typing as t
from werkzeug.local import LocalProxy
from .globals import request
if t.TYPE_CHECKING: # pragma: no cover
from .sansio.app import App
@LocalProxy
def wsgi_errors_stream() -> t.TextIO:
"""Find the most appropriate error stream for the application. If a request
is active, log to ``wsgi.errors``, otherwise use ``sys.stderr``.
If you configure your own :class:`logging.StreamHandler`, you may want to
use this for the stream. If you are using file or dict configuration and
can't import this directly, you can refer to it as
``ext://flask.logging.wsgi_errors_stream``.
"""
if request:
return request.environ["wsgi.errors"] # type: ignore[no-any-return]
return sys.stderr
def has_level_handler(logger: logging.Logger) -> bool:
"""Check if there is a handler in the logging chain that will handle the
given logger's :meth:`effective level <~logging.Logger.getEffectiveLevel>`.
"""
level = logger.getEffectiveLevel()
current = logger
while current:
if any(handler.level <= level for handler in current.handlers):
return True
if not current.propagate:
break
current = current.parent # type: ignore
return False
#: Log messages to :func:`~flask.logging.wsgi_errors_stream` with the format
#: ``[%(asctime)s] %(levelname)s in %(module)s: %(message)s``.
default_handler = logging.StreamHandler(wsgi_errors_stream) # type: ignore
default_handler.setFormatter(
logging.Formatter("[%(asctime)s] %(levelname)s in %(module)s: %(message)s")
)
def create_logger(app: App) -> logging.Logger:
"""Get the Flask app's logger and configure it if needed.
The logger name will be the same as
:attr:`app.import_name <flask.Flask.name>`.
When :attr:`~flask.Flask.debug` is enabled, set the logger level to
:data:`logging.DEBUG` if it is not set.
If there is no handler for the logger's effective level, add a
:class:`~logging.StreamHandler` for
:func:`~flask.logging.wsgi_errors_stream` with a basic format.
"""
logger = logging.getLogger(app.name)
if app.debug and not logger.level:
logger.setLevel(logging.DEBUG)
if not has_level_handler(logger):
logger.addHandler(default_handler)
return logger