Contain logger configuration (#318)

* only configure the iohub logger

* add regression testing

Author: ziw-liu

iohub/__init__.py

@@ -14,9 +14,18 @@
 __all__ = ["open_ome_zarr", "read_images"]
 
 
-_level = os.environ.get("IOHUB_LOG_LEVEL", logging.INFO)
-if str(_level).isdigit():
-    _level = int(_level)
+def _configure_logging():
+    """Configure logging for iohub."""
+    level = os.environ.get("IOHUB_LOG_LEVEL", logging.INFO)
+    if str(level).isdigit():
+        level = int(level)
+    iohub_logger = logging.getLogger(__name__)
+    iohub_logger.setLevel(level)
+    stream_handler = logging.StreamHandler()
+    stream_handler.setFormatter(
+        logging.Formatter(fmt="%(levelname)s:%(name)s:%(message)s")
+    )
+    iohub_logger.addHandler(stream_handler)
 
-logging.basicConfig()
-logging.getLogger(__name__).setLevel(_level)
+
+_configure_logging()

tests/test_log_level.py

@@ -0,0 +1,11 @@
+import logging
+
+import iohub  # noqa: F401
+
+
+def test_external_logging_level(caplog):
+    with caplog.at_level(logging.DEBUG):
+        iohub_logger = logging.getLogger("iohub")
+        assert iohub_logger.getEffectiveLevel() == logging.INFO
+        other_logger = logging.getLogger(__name__)
+        assert other_logger.getEffectiveLevel() == logging.DEBUG