Initial commit: Javis project

javis-slave/src/javis_slave/logging_setup.py

@@ -0,0 +1,46 @@
+"""Minimal stdlib logging helper (kept dependency-free from the javis package).
+
+Logs go to stderr and to a rotating file under ``<config dir>/logs/slave.log``
+so tablet/Pi problems can be diagnosed after the fact.
+"""
+from __future__ import annotations
+
+import logging
+import sys
+from logging.handlers import RotatingFileHandler
+
+_configured = False
+_FMT = logging.Formatter(
+    "%(asctime)s | %(levelname)-7s | %(name)s - %(message)s", datefmt="%H:%M:%S",
+)
+
+
+def _configure_once() -> None:
+    global _configured
+    if _configured:
+        return
+    root = logging.getLogger("javis_slave")
+    root.setLevel(logging.INFO)
+    root.propagate = False
+
+    handler = logging.StreamHandler(sys.stderr)
+    handler.setFormatter(_FMT)
+    root.addHandler(handler)
+
+    try:
+        from .config import config_dir
+        log_dir = config_dir() / "logs"
+        log_dir.mkdir(parents=True, exist_ok=True)
+        fh = RotatingFileHandler(log_dir / "slave.log", maxBytes=2_000_000,
+                                 backupCount=3, encoding="utf-8")
+        fh.setFormatter(logging.Formatter(
+            "%(asctime)s | %(levelname)-7s | %(name)s - %(message)s"))
+        root.addHandler(fh)
+    except Exception as exc:  # noqa: BLE001  (read-only FS etc. — stderr still works)
+        root.warning(f"file logging disabled: {exc}")
+    _configured = True
+
+
+def get_logger(name: str) -> logging.Logger:
+    _configure_once()
+    return logging.getLogger(f"javis_slave.{name}")