Open
Description
- I've checked docs and closed issues for possible solutions.
- I can't find my issue in the FAQ.
Describe the bug
RichHandler does not handle exceptions raised while formatting the log message, unlike
default builtin Python handlers.
Simple example
Below I set up the logger with RichHandler and provide bad arguments to the log.warning call.
>>> import logging
>>> from rich.logging import RichHandler
>>> log = logging.getLogger(__name__)
>>> log.handlers = [RichHandler()]
>>> log.warning("{bad}", 123)
... print("logic continues")
---------------------------------------------------------------------------
TypeError Traceback (most recent call last)
Cell In[12], line 1
----> 1 log.warning("{bad}", 123)
2 print("logic continues")
...
File ~/.local/share/pyenv/versions/3.8.19/lib/python3.8/logging/__init__.py:373, in LogRecord.getMessage(self)
371 msg = str(self.msg)
372 if self.args:
--> 373 msg = msg % self.args
374 return msg
TypeError: not all arguments converted during string formatting
>>>I expected the logic to continue running with message logic continues printed. Compare
this with the default behaviour:
>>> import logging
>>> log = logging.getLogger(__name__)
>>> log.handlers = [logging.StreamHandler()]
>>> log.warning("{bad}", 123)
... print("logic continues")
--- Logging error ---
Traceback (most recent call last):
File "/home/sarunas/.local/share/pyenv/versions/3.8.19/lib/python3.8/logging/__init__.py", line 1085, in emit
msg = self.format(record)
...
File "<ipython-input-7-ee55d4d922a6>", line 1, in <module>
log.warning("{bad}", 123)
Message: '{bad}'
Arguments: (123,)
logic continues
>>>Here the exception got handled and my logic continued running with the message being printed.
The cause
I had a quick glance at RichHandler implementation and compared it with StreamHandler. I think the issue lies in emit method implementation:
class StreamHandler(Handler):
...
def emit(self, record):
try:
msg = self.format(record)
stream = self.stream
# issue 35046: merged two stream.writes into one.
stream.write(msg + self.terminator)
self.flush()
except RecursionError: # See issue 36272
raise
except Exception:
self.handleError(record)and
class RichHandler(Handler):
...
def emit(self, record: LogRecord) -> None:
"""Invoked by logging."""
message = self.format(record)
traceback = None
...In StreamHandler, the self.format(record) call is tucked under the try statement while in RichHandler it is not.