Add documentation for disabling file logging

Author: trey-stafford

README.md

@@ -59,6 +59,20 @@ Commands:
   nrt     Run NRT Sea Ice ECDR.
 ```
 
+### Logging
+
+By default, logs are written to disk at
+`/share/apps/G02202_V5/{ECDR_PRODUCT_VERSION}/{YYYY-MM-DD}.log`. Up to 31 of
+these logs can exist at once (older log files get removed).
+
+During large re-processing efforts, it may be desirable to temporarily disable
+logging to improve processing speed and reduce disk usage. To do so, set the
+`DISABLE_FILE_LOGGING` envvar to `TRUE`.
+
+```
+export DISABLE_FILE_LOGGING=TRUE
+```
+
 ## Development/contributing
 
 See [doc/development.md](doc/development.md) for more information.

seaice_ecdr/__init__.py

@@ -23,13 +23,21 @@
 # regular ops runs up to a certain date, which might help w/ debugging
 # issues...Larger reprocessing efforts could disable file logging (or change the
 # level?) for speed and space consideration issues.
-do_not_log = os.environ.get("DISABLE_FILE_LOGGING")
+disable_file_logging = os.environ.get("DISABLE_FILE_LOGGING")
+do_not_log = disable_file_logging is not None and disable_file_logging.upper() in (
+    "TRUE",
+    "YES",
+)
+
 if not do_not_log:
     # One file per day.
     file_sink_fp = LOGS_DIR / "{time:%Y-%m-%d}.log"
+    logger.debug(f"Logging to {file_sink_fp}")
     logger.add(
         file_sink_fp,
         level=DEFAULT_LOG_LEVEL,
         # Retain logs for up to a month.
         retention=31,
     )
+else:
+    logger.debug(f"Not logging to file (DISABLE_FILE_LOGGING={disable_file_logging}).")