feat(TrialLogHandler): Hook into Python's logging

experitur/core/log_handler.py

@@ -0,0 +1,45 @@
+import logging
+
+from typing import TYPE_CHECKING
+
+if TYPE_CHECKING:
+    from experitur.core.trial import Trial
+
+
+class TrialLogHandler(logging.Handler):
+    """
+    Hook into Python's logging to save entries in the trial log.
+
+    Example:
+        with TrialLogHandler(trial):
+            ...
+    """
+
+    def __init__(self, trial: "Trial"):
+        super().__init__()
+        self.trial = trial
+
+    def emit(self, record):
+        """
+        Emit a record.
+
+        If a formatter is specified, it is used to format the record.
+        The record is then written to the stream with a trailing newline.  If
+        exception information is present, it is formatted using
+        traceback.print_exception and appended to the stream.  If the stream
+        has an 'encoding' attribute, it is used to determine how to do the
+        output to the stream.
+        """
+        try:
+            msg = self.format(record)
+            self.trial.log_msg(msg)
+        except RecursionError:
+            raise
+        except Exception:  # pylint: disable=broad-except
+            self.handleError(record)
+
+    def __enter__(self):
+        logging.root.addHandler(self)
+
+    def __exit__(self, *_, **__):
+        logging.root.removeHandler(self)