Add logging module

Based on qubes.log module from core-admin

qubesmgmt/log.py

@@ -0,0 +1,110 @@
+#
+# The Qubes OS Project, https://www.qubes-os.org/
+#
+# Copyright (C) 2014-2015  Joanna Rutkowska <joanna@invisiblethingslab.com>
+# Copyright (C) 2014-2015  Wojtek Porczyk <woju@invisiblethingslab.com>
+#
+# This program 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 program 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 program; if not, write to the Free Software Foundation, Inc.,
+# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+#
+
+'''Qubes logging routines
+
+See also: :py:attr:`qubes.vm.qubesvm.QubesVM.log`
+'''
+
+import logging
+import sys
+
+import dbus
+
+FORMAT_CONSOLE = '%(message)s'
+FORMAT_LOG = '%(asctime)s %(message)s'
+FORMAT_DEBUG = '%(asctime)s ' \
+    '[%(processName)s %(module)s.%(funcName)s:%(lineno)d] %(name)s: %(message)s'
+
+formatter_console = logging.Formatter(FORMAT_CONSOLE)
+formatter_log = logging.Formatter(FORMAT_LOG)
+formatter_debug = logging.Formatter(FORMAT_DEBUG)
+
+
+class DBusHandler(logging.Handler):
+    '''Handler which displays records as DBus notifications'''
+
+    #: mapping of loglevels to icons
+    app_icons = {
+        logging.ERROR:      'dialog-error',
+        logging.WARNING:    'dialog-warning',
+        logging.NOTSET:     'dialog-information',
+    }
+
+    def __init__(self, *args, **kwargs):
+        super(DBusHandler, self).__init__(*args, **kwargs)
+
+        self._notify_object = dbus.SessionBus().get_object(
+            'org.freedesktop.Notifications', '/org/freedesktop/Notifications')
+
+
+    def emit(self, record):
+        app_icon = self.app_icons[
+            max(level for level in self.app_icons if level <= record.levelno)]
+
+        try:
+            # https://developer.gnome.org/notification-spec/#command-notify
+            self._notify_object.Notify(
+                'Qubes',    # STRING app_name
+                0,          # UINT32 replaces_id
+                app_icon,   # STRING app_icon
+                record.msg, # STRING summary
+                '',         # STRING body
+                (),         # ARRAY actions
+                {},         # DICT hints
+                0,          # INT32 timeout
+                dbus_interface='org.freedesktop.Notifications')
+        except dbus.DBusException:
+            pass
+
+
+def enable():
+    '''Enable global logging
+
+    Use :py:mod:`logging` module from standard library to log messages.
+
+    >>> import qubes.log
+    >>> qubes.log.enable()          # doctest: +SKIP
+    >>> import logging
+    >>> logging.warning('Foobar')   # doctest: +SKIP
+    '''
+
+    if logging.root.handlers:
+        return
+
+    handler_console = logging.StreamHandler(sys.stderr)
+    handler_console.setFormatter(formatter_console)
+    logging.root.addHandler(handler_console)
+
+    logging.root.setLevel(logging.INFO)
+
+
+def enable_debug():
+    '''Enable debug logging
+
+    Enable more messages and additional info to message format.
+    '''
+
+    enable()
+    logging.root.setLevel(logging.DEBUG)
+
+    for handler in logging.root.handlers:
+        handler.setFormatter(formatter_debug)