ENH: replace verbosity with standard logging patterns

Using verbosity and setLevel within the library is an antipattern.

The approach shall be that the end client script
sets the logging level, format, etc. instead.

src/fmu/dataio/_design_kw.py

@@ -7,14 +7,15 @@
 
 from __future__ import annotations
 
-import logging
 import re
 import shlex
 from typing import Any, Final, Iterable
 
+from ._logging import null_logger
+
 _STATUS_FILE_NAME: Final = "DESIGN_KW.OK"
 
-_logger: Final = logging.getLogger(__name__)
+_logger: Final = null_logger(__name__)
 
 
 def run(

src/fmu/dataio/_filedata_provider.py

@@ -5,14 +5,15 @@
 """
 from __future__ import annotations
 
-import logging
 from copy import deepcopy
 from dataclasses import dataclass, field
 from pathlib import Path
 from typing import Any, Final, Optional
 from warnings import warn
 
-logger: Final = logging.getLogger(__name__)
+from ._logging import null_logger
+
+logger: Final = null_logger(__name__)
 
 
 @dataclass
@@ -33,7 +34,6 @@ class _FileDataProvider:
     rootpath: Path = field(default_factory=Path)
     itername: str = ""
     realname: str = ""
-    verbosity: str = "CRITICAL"
 
     # storing results in these variables
     relative_path: Optional[str] = field(default="", init=False)
@@ -43,8 +43,6 @@ class _FileDataProvider:
     checksum_md5: Optional[str] = field(default="", init=False)
 
     def __post_init__(self) -> None:
-        logger.setLevel(level=self.verbosity)
-
         if self.dataio.name:
             self.name = self.dataio.name
         else:

src/fmu/dataio/_fmu_provider.py

@@ -9,7 +9,6 @@
 from __future__ import annotations
 
 import json
-import logging
 import pathlib
 import re
 from copy import deepcopy
@@ -22,12 +21,13 @@
 from fmu.config import utilities as ut
 
 from . import _utils
+from ._logging import null_logger
 
 # case metadata relative to rootpath
 ERT2_RELATIVE_CASE_METADATA_FILE: Final = "share/metadata/fmu_case.yml"
 RESTART_PATH_ENVNAME: Final = "RESTART_FROM_PATH"
 
-logger: Final = logging.getLogger(__name__)
+logger: Final = null_logger(__name__)
 
 
 def _get_folderlist(current: Path) -> list:
@@ -49,7 +49,6 @@ class _FmuProvider:
     """Class for detecting the run environment (e.g. an ERT2) and provide metadata."""
 
     dataio: Any
-    verbosity: str = "CRITICAL"
 
     provider: Optional[str] = field(default=None, init=False)
     is_fmurun: Optional[bool] = field(default=False, init=False)
@@ -68,8 +67,6 @@ class _FmuProvider:
     rootpath: Optional[Path] = field(default=None, init=False)
 
     def __post_init__(self) -> None:
-        logger.setLevel(level=self.verbosity)
-
         self.rootpath = Path(self.dataio._rootpath.absolute())
 
         self.rootpath_initial = self.rootpath

src/fmu/dataio/_logging.py

@@ -0,0 +1,32 @@
+from __future__ import annotations
+
+import logging
+
+
+def null_logger(name: str) -> logging.Logger:
+    """
+    Create and return a logger with a NullHandler.
+
+    This function creates a logger for the specified name and attaches a
+    NullHandler to it. The NullHandler prevents logging messages from being
+    automatically output to the console or other default handlers. This is
+    particularly useful in library modules where you want to provide the
+    users of the library the flexibility to configure their own logging behavior.
+
+    Args:
+        name (str): The name of the logger to be created. This is typically
+                    the name of the module in which the logger is
+                    created (e.g., using __name__).
+
+    Returns:
+        logging.Logger: A logger object configured with a NullHandler.
+
+    Example:
+        # In a library module
+        logger = null_logger(__name__)
+        logger.info("This info won't be logged to the console by default.")
+    """
+
+    logger = logging.getLogger(name)
+    logger.addHandler(logging.NullHandler())
+    return logger

src/fmu/dataio/_metadata.py

@@ -8,7 +8,6 @@
 
 import datetime
 import getpass
-import logging
 from dataclasses import dataclass, field
 from datetime import timezone
 from pathlib import Path
@@ -29,7 +28,9 @@
     read_named_envvar,
 )
 
-logger: Final = logging.getLogger(__name__)
+from ._logging import null_logger
+
+logger: Final = null_logger(__name__)
 
 
 class ConfigurationError(ValueError):
@@ -214,7 +215,6 @@ class _MetaData:
     # input variables
     obj: Any
     dataio: Any
-    verbosity: str = "CRITICAL"
     compute_md5: bool = True
 
     # storage state variables
@@ -238,7 +238,6 @@ class _MetaData:
     meta_existing: dict = field(default_factory=dict, init=False)
 
     def __post_init__(self) -> None:
-        logger.setLevel(level=self.verbosity)
         logger.info("Initialize _MetaData instance.")
 
         # one special case is that obj is a file path, and dataio.reuse_metadata_rule is
@@ -268,7 +267,7 @@ def _get_case_metadata(self) -> object:
 
         The _FmuDataProvider is ran first -> self.fmudata
         """
-        self.fmudata = _FmuProvider(self.dataio, verbosity=self.verbosity)
+        self.fmudata = _FmuProvider(self.dataio)
         self.fmudata.detect_provider()
         logger.info("FMU provider is %s", self.fmudata.provider)
         return self.fmudata.case_metadata
@@ -281,7 +280,7 @@ def _populate_meta_fmu(self) -> None:
 
         The _FmuDataProvider is ran first -> self.fmudata
         """
-        self.fmudata = _FmuProvider(self.dataio, verbosity=self.verbosity)
+        self.fmudata = _FmuProvider(self.dataio)
         self.fmudata.detect_provider()
         logger.info("FMU provider is %s", self.fmudata.provider)
         self.meta_fmu = self.fmudata.metadata
@@ -309,7 +308,6 @@ def _populate_meta_file(self) -> None:
             Path(self.rootpath),
             self.fmudata.iter_name,
             self.fmudata.real_name,
-            self.verbosity,
         )
         fdata.derive_filedata()
 

src/fmu/dataio/_objectdata_provider.py

@@ -85,7 +85,6 @@
 """
 from __future__ import annotations
 
-import logging
 from dataclasses import dataclass, field
 from datetime import datetime as dt
 from pathlib import Path
@@ -97,9 +96,10 @@
 import xtgeo
 
 from ._definitions import ALLOWED_CONTENTS, STANDARD_TABLE_INDEX_COLUMNS, _ValidFormats
+from ._logging import null_logger
 from ._utils import generate_description, parse_timedata
 
-logger: Final = logging.getLogger(__name__)
+logger: Final = null_logger(__name__)
 
 
 class ConfigurationError(ValueError):

src/fmu/dataio/_utils.py

@@ -4,7 +4,6 @@
 import contextlib
 import hashlib
 import json
-import logging
 import os
 import shutil
 import uuid
@@ -21,8 +20,9 @@
 from fmu.config import utilities as ut
 
 from . import _design_kw
+from ._logging import null_logger
 
-logger: Final = logging.getLogger(__name__)
+logger: Final = null_logger(__name__)
 
 
 def detect_inside_rms() -> bool:
@@ -75,10 +75,8 @@ def export_metadata_file(
     file: Path,
     metadata: dict,
     savefmt: Literal["yaml", "json"] = "yaml",
-    verbosity: str = "WARNING",
 ) -> None:
     """Export genericly and ordered to the complementary metadata file."""
-    logger.setLevel(level=verbosity)
     if not metadata:
         raise RuntimeError(
             "Export of metadata was requested, but no metadata are present."