[core/config] enable logging into a log file

Re-enable the -f | --logfile parameter, but still default to logging to
stderr.

Also, add a "debug" module that is automatically displayed if a bar is
run in debug mode (thanks to @bbernhard for the excellent suggestion)

fixes #614

bumblebee-status

@@ -1,5 +1,6 @@
 #!/usr/bin/env python
 
+import os
 import sys
 import json
 import select
@@ -38,13 +39,22 @@ def handle_input(output):
     poll.unregister(sys.stdin.fileno())
 
 def main():
-    logging.basicConfig(
-        level=logging.DEBUG,
-        format="[%(asctime)s] %(module)-16s %(levelname)-8s %(message)s",
-        stream=sys.stderr
-    )
-
     config = core.config.Config(sys.argv[1:])
+
+    level = logging.DEBUG if config.debug() else logging.ERROR
+    if config.logfile():
+        logging.basicConfig(
+            level=level,
+            format="[%(asctime)s] %(module)-16s %(levelname)-8s %(message)s",
+            filename=os.path.abspath(os.path.expanduser(config.logfile()))
+        )
+    else:
+        logging.basicConfig(
+            level=level,
+            format="[%(asctime)s] %(module)-16s %(levelname)-8s %(message)s",
+            stream=sys.stderr
+        )
+
     theme = core.theme.Theme(config.theme(), config.iconset())
     output = core.output.i3(theme, config)
     modules = []
@@ -53,6 +63,9 @@ def main():
     input_thread.daemon = True
     input_thread.start()
 
+    if config.debug():
+        modules.append(core.module.load('debug', config, theme))
+
     for module in config.modules():
         modules.append(core.module.load(module, config, theme))
     output.modules(modules)

core/config.py

@@ -26,6 +26,7 @@ class Config(util.store.Store):
             help='Specify a list of modules to hide when not in warning/error state')
         parser.add_argument('-d', '--debug', action='store_true',
             help='Add debug fields to i3 output')
+        parser.add_argument('-f', '--logfile', help='destination for the debug log file, if -d|--debug is specified; defaults to stderr')
         self.__args = parser.parse_args(args)
 
         parameters = [ item for sub in self.__args.parameters for item in sub ]
@@ -45,6 +46,9 @@ class Config(util.store.Store):
     def debug(self):
         return self.__args.debug
 
+    def logfile(self):
+        return self.__args.logfile
+
     def theme(self):
         return self.__args.theme
 

modules/core/debug.py

@@ -0,0 +1,22 @@
+# pylint: disable=C0111,R0903
+
+"""Shows that debug is enabled"""
+
+import platform
+
+import core.module
+import core.widget
+import core.decorators
+
+class Module(core.module.Module):
+    @core.decorators.every(minutes=60)
+    def __init__(self, config, theme):
+        super().__init__(config, theme, core.widget.Widget(self.full_text))
+
+    def full_text(self, widgets):
+        return 'debug'
+
+    def state(self, widget):
+        return 'warning'
+
+# vim: tabstop=8 expandtab shiftwidth=4 softtabstop=4