core/logging: set exc_info during logging automatically

src/promnesia/__main__.py

@@ -106,7 +106,7 @@ def do_index(
     if len(errors) > 0:
         logger.error('%d errors, printing them out:', len(errors))
         for e in errors:
-            logger.error('    %s', e, exc_info=e)
+            logger.exception(e)
         logger.error('%d errors, exit code 1', len(errors))
         sys.exit(1)
 

src/promnesia/logging.py

@@ -72,6 +72,7 @@ def setup_logger(logger: logging.Logger, level: LevelIsh) -> None:
         formatter = logging.Formatter(fmt=FORMAT_NOCOLOR, datefmt=DATEFMT)
         use_logzero = False
 
+    logger.addFilter(AddExceptionTraceback())
     if use_logzero and not COLLAPSE_DEBUG_LOGS: # all set, nothing to do
         # 'simple' setup
         logzero.setup_logger(logger.name, level=lvl, formatter=formatter)
@@ -104,6 +105,24 @@ def isEnabledFor_lazyinit(*args, logger=logger, orig=logger.isEnabledFor, **kwar
         return cast(LazyLogger, logger)
 
 
+# by default, logging.exception isn't logging traceback
+# which is a bit annoying since we have to
+# also see https://stackoverflow.com/questions/75121925/why-doesnt-python-logging-exception-method-log-traceback-by-default
+# tod also amend by post about defensive error handling?
+class AddExceptionTraceback(logging.Filter):
+    def filter(self, record):
+        s = super().filter(record)
+        if s is False:
+            return False
+        if record.levelname == 'ERROR':
+            exc = record.msg
+            if isinstance(exc, BaseException):
+                if record.exc_info is None or record.exc_info == (None, None, None):
+                    exc_info = (type(exc), exc, exc.__traceback__)
+                    record.exc_info = exc_info
+        return s
+
+
 # todo also save full log in a file?
 class CollapseDebugHandler(logging.StreamHandler):
     '''