[BugFix] Fix logging disabling bug and add tests (#1218)

SUMMARY:
Fixed logging and clear loggers enabling/disabling bug. Previously, any
value on the right environment variables would disable logging. Now, we
explicitly check for `true`

TEST PLAN:
Added unit tests for enabling logging.
`make test` passes

---------

Signed-off-by: Aman Gupta <[email protected]>
Co-authored-by: Dipika Sikka <[email protected]>

Author: aman2304

src/llmcompressor/logger.py

@@ -53,9 +53,9 @@ class LoggerConfig:
     metrics_disabled: bool = False
 
 
-def configure_logger(config: Optional[LoggerConfig] = None):
+def configure_logger(config: Optional[LoggerConfig] = None) -> None:
     """
-    Configure the metrics for LLM Compressor.
+    Configure the logger for LLM Compressor.
     This function sets up the console and file logging
     as per the specified or default parameters.
 
@@ -68,9 +68,9 @@ def configure_logger(config: Optional[LoggerConfig] = None):
 
     # env vars get priority
     if (disabled := os.getenv("LLM_COMPRESSOR_LOG_DISABLED")) is not None:
-        logger_config.disabled = disabled.lower()
+        logger_config.disabled = disabled.lower() == "true"
     if (clear_loggers := os.getenv("LLM_COMPRESSOR_CLEAR_LOGGERS")) is not None:
-        logger_config.clear_loggers = clear_loggers.lower()
+        logger_config.clear_loggers = clear_loggers.lower() == "true"
     if (console_log_level := os.getenv("LLM_COMPRESSOR_LOG_LEVEL")) is not None:
         logger_config.console_log_level = console_log_level.upper()
     if (log_file := os.getenv("LLM_COMPRESSOR_LOG_FILE")) is not None:

tests/unit/test_logger.py

@@ -103,3 +103,16 @@ def test_environment_variable_disable_logging(monkeypatch, capsys):
     captured = capsys.readouterr()
     assert captured.out == ""
     assert captured.err == ""
+
+
+def test_environment_variable_enable_logging(monkeypatch, capsys):
+    # Test environment variable to enable logging
+    monkeypatch.setenv("LLM_COMPRESSOR_LOG_DISABLED", "false")
+
+    configure_logger(config=LoggerConfig())
+    logger.info("Info message")
+    logger.error("Error message")
+
+    captured = capsys.readouterr()
+    assert captured.out.count("Info message") == 1
+    assert captured.out.count("Error message") == 1