Logging: added set and reset logging level method, small logging modifications.

1 files changed, 101 insertions, 14 deletions

diff --git a/rumba/log.py b/rumba/log.py
index e856b42..0e3f0dc 100644
--- a/rumba/log.py
+++ b/rumba/log.py
@@ -1,3 +1,22 @@
+#
+# Logging wrapper for Rumba
+#
+#    Marco Capitani <m.capitani@nextworks.it>
+#
+# This library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 2.1 of the License, or (at your option) any later version.
+#
+# This library is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with this library; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+# MA  02110-1301  USA
 import logging
 
 import sys
@@ -5,21 +24,43 @@ import sys
 import multiprocessing
 
 
+loggers_set = set()
+
+
+class RumbaFormatter(logging.Formatter):
+    """The logging.Formatter subclass used by RUMBA"""
+
+    level_name_table = {
+        'CRITICAL': 'CRT',
+        'ERROR': 'ERR',
+        'WARNING': 'WRN',
+        'INFO': 'INF',
+        'DEBUG': 'DBG'
+    }
+
+    def __init__(self):
+        super(RumbaFormatter, self).__init__(
+            fmt='{asctime} | {levelname:3.3} | '
+                '{name:11.11} | {message}',
+            style='{',
+            datefmt='%H:%M:%S')
+
+    def format(self, record):
+        record.name = record.name.split('.')[-1]
+        record.levelname = self.level_name_table[record.levelname]
+        return super(RumbaFormatter, self).format(record)
+
+
 def setup():
+    """Configures the logging framework with default values."""
     handler = logging.StreamHandler(sys.stdout)
     handler.lock = multiprocessing.RLock()
-    logging.basicConfig(format='{asctime} | {levelname:3.3} | '
-                               '{name:11.11} | {message}',
-                        style='{',
-                        datefmt='%H:%M:%S',
-                        handlers=[handler],
-                        level=logging.DEBUG)
-    logging.addLevelName(logging.CRITICAL, 'CRT')
-    logging.addLevelName(logging.ERROR, 'ERR')
-    logging.addLevelName(logging.WARNING, 'WRN')
-    logging.addLevelName(logging.INFO, 'INF')
-    logging.addLevelName(logging.DEBUG, 'DBG')
+    handler.setLevel(logging.DEBUG)
+    formatter = RumbaFormatter()
+    handler.setFormatter(formatter)
+    logging.basicConfig(handlers=[handler], level=logging.DEBUG)
     logging.getLogger('').setLevel(logging.ERROR)
+    logging.getLogger('rumba').setLevel(logging.DEBUG)
 
 
 # Used for the first call, in order to configure logging
@@ -40,6 +81,52 @@ _get_logger = _get_logger_with_setup
 
 
 def get_logger(name):
-    logger = _get_logger(name.split('.')[-1])
-    logger.setLevel(logging.DEBUG)
-    return logger
+    """
+    Returns the logger named <name>.
+    <name> should be the module name, for consistency. If setup has not been
+    called yet, it will call it first.
+    :param name: the name of the desired logger
+    :return: The logger
+    """
+    return _get_logger(name)
+
+
+def set_logging_level(level, name=None):
+    """
+    Set the current logging level to <level> for logger named <name>.
+    If name is not specified, sets the logging level for all rumba loggers.
+    Accepted levels are: 
+        DEBUG == 10, 
+        INFO == 20, 
+        WARNING == 30, 
+        ERROR == 40, 
+        CRITICAL == 50,
+        NOTSET == 0
+    (resets the logger: its level is set to the default or its parents' level)
+    :param level: the desired logging level.
+    :param name: The name of the logger to configure
+    """
+    if name is None:
+        if level == 'NOTSET' or level == 0:
+            set_logging_level(logging.INFO)
+            return
+        name = 'rumba'
+    if (level == 'NOTSET' or level == 0) and name == '':
+        set_logging_level(logging.ERROR, '')
+        return
+    logger = get_logger(name)
+    loggers_set.add(logger)
+    logger.setLevel(level)
+
+
+def reset_logging_level():
+    """
+    Resets the current logging levels to the defaults.
+    Defaults are: rumba           -> INFO,
+                  everything else -> ERROR
+    """
+    # Un-sets every logger previously set
+    for logger in loggers_set:
+        logger.setLevel(logging.NOTSET)
+    set_logging_level(logging.INFO)
+    set_logging_level(logging.ERROR, '')