Make it possible to skip logging before the actual call

Author: hmpf

python/nav/util.py

@@ -509,3 +509,20 @@ def _range_to_str(x, y):
             return str(x)
         else:
             return "{}-{}".format(x, y)
+
+
+def check_log_level(logger, loglevel):
+    """
+    Check that the level of the logger is equal to or below loglevel
+
+    Use before possibly expensive logging operations, like calling logging in
+    a loop or building an expensive object that will be logged and thrown away.
+
+    Avoid this classic mistake:
+
+        logger.info("%s", expensive_function())
+    """
+    level = logger.getEffectiveLevel()
+    if level <= loglevel:
+        return True
+    return False

python/nav/web/auth/remote_user.py

@@ -19,9 +19,12 @@
 import logging
 from os.path import join
 
+from django.conf import settings
+
 from nav.auditlog.models import LogEntry
 from nav.config import NAVConfigParser
 from nav.models.profiles import Account
+from nav.util import check_log_level
 from nav.web.auth.utils import ACCOUNT_ID_VAR
 
 try:
@@ -179,6 +182,10 @@ def get_username(request):
     if not request:
         return None
 
+    if settings.DEBUG or check_log_level(_logger, logging.DEBUG):
+        for metakey, value in request.META.items():
+            if metakey == metakey.upper():
+                _logger.debug('%s: %s', metakey, value)
     workaround = 'none'
     try:
         workaround_config = _config.get('remote-user', 'workaround')