begin using logging

src/delta_barth/constants.py

@@ -4,6 +4,8 @@ from typing import Final
 
 from delta_barth.types import DualDict, HttpContentHeaders
 
+# ** config
+
 # ** lib path
 lib_path = Path(__file__).parent
 assert lib_path is not None, "lib path not resolved"
@@ -12,6 +14,12 @@ dummy_data_pth = LIB_PATH / "_dummy_data"
 assert dummy_data_pth.exists(), f"dummy data path not found: {dummy_data_pth}"
 DUMMY_DATA_PATH: Final[Path] = dummy_data_pth
 
+# ** logging
+ENABLE_LOGGING: Final[bool] = True
+LOGGING_TO_FILE: Final[bool] = True
+LOGGING_TO_STDERR: Final[bool] = True
+
+
 # ** error handling
 DEFAULT_INTERNAL_ERR_CODE: Final[int] = 100
 DEFAULT_API_ERR_CODE: Final[int] = 400

src/delta_barth/errors.py

@@ -1,11 +1,13 @@
 from __future__ import annotations
 
+import traceback
 import typing as t
 from collections.abc import Callable
 from functools import wraps
 from typing import Any, Final
 
 from delta_barth.constants import DEFAULT_API_ERR_CODE, DEFAULT_INTERNAL_ERR_CODE
+from delta_barth.logging import logger_wrapped_results as logger
 from delta_barth.types import DataPipeStates, Status
 
 if t.TYPE_CHECKING:
@@ -237,6 +239,11 @@ def wrap_result(
                 status = ResultWrapper(
                     result=NotSet(), exception=err, code_on_error=code_on_error
                 )
+                fmt_exc = traceback.format_exception(err)
+                exc_str = "".join(fmt_exc)
+                logger.error(
+                    "An exception in routine %s occured:\n%s", func.__name__, exc_str
+                )
 
             return status
 

src/delta_barth/logging.py

@@ -0,0 +1,53 @@
+from __future__ import annotations
+
+import logging
+import logging.handlers
+from pathlib import Path
+from time import gmtime
+from typing import Final
+
+from delta_barth.constants import ENABLE_LOGGING, LIB_PATH, LOGGING_TO_FILE, LOGGING_TO_STDERR
+
+# ** config
+logging.Formatter.converter = gmtime
+LOG_FMT: Final[str] = "%(asctime)s | lang_main:%(module)s:%(levelname)s | %(message)s"
+LOG_DATE_FMT: Final[str] = "%Y-%m-%d %H:%M:%S +0000"
+LOG_FILE_FOLDER: Final[Path] = LIB_PATH / "logs"
+if not LOG_FILE_FOLDER.exists():
+    LOG_FILE_FOLDER.mkdir(parents=True)
+
+LOG_FILE_PATH: Final[Path] = LOG_FILE_FOLDER / "lang-main.log"
+LOGGING_LEVEL_STDERR: Final[int] = logging.INFO
+LOGGING_LEVEL_FILE: Final[int] = logging.DEBUG
+
+# ** formatters
+logger_all_formater = logging.Formatter(fmt=LOG_FMT, datefmt=LOG_DATE_FMT)
+
+# ** handlers
+null_handler = logging.NullHandler()
+if ENABLE_LOGGING and LOGGING_TO_STDERR:
+    logger_all_handler_stderr = logging.StreamHandler()
+    logger_all_handler_stderr.setLevel(LOGGING_LEVEL_STDERR)
+    logger_all_handler_stderr.setFormatter(logger_all_formater)
+else:  # pragma: no cover
+    logger_all_handler_stderr = null_handler
+
+if ENABLE_LOGGING and LOGGING_TO_FILE:
+    logger_all_handler_file = logging.handlers.RotatingFileHandler(
+        LOG_FILE_PATH,
+        encoding="utf-8",
+        maxBytes=5_242_880,
+        backupCount=1,
+    )
+    logger_all_handler_file.setLevel(LOGGING_LEVEL_FILE)
+    logger_all_handler_file.setFormatter(logger_all_formater)
+else:  # pragma: no cover
+    logger_all_handler_file = null_handler
+
+# ** loggers and configuration
+logger_all = logging.getLogger("delta_barth")
+logger_all.addHandler(logger_all_handler_stderr)
+logger_all.addHandler(logger_all_handler_file)
+
+logger_wrapped_results = logging.getLogger("delta_barth.wrapped_results")
+logger_wrapped_results.setLevel(logging.DEBUG)