When developing libraries, you’ll probably need to use the
N.B. This is part of the standard library since Python 2.7 / 3.1, so the version here is for use with earlier Python versions.
import logging try: from logging import NullHandler except ImportError: from logutils import NullHandler # use this in all your library's subpackages/submodules logger = logging.getLogger(__name__) # use this just in your library's top-level package logger.addHandler(NullHandler())
This handler does nothing. It’s intended to be used to avoid the “No handlers could be found for logger XXX” one-off warning. This is important for library code, which may contain code to log events. If a user of the library does not configure logging, the one-off warning might be produced; to avoid this, the library developer simply needs to instantiate a NullHandler and add it to the top-level logger of the library module or package.
Since this handler does nothing, it has no underlying I/O to protect against multi-threaded access, so this method returns None.
Emit a record. This does nothing and shouldn’t be called during normal
processing, unless you redefine
Handle a record. Does nothing in this class, but in other handlers it typically filters and then emits the record in a thread-safe way.