Implemented logging and configuration files

.gitignore

@@ -1,3 +1,6 @@
+# backups
+*~
+
 # script-generated
 aliases*.json
 nodedb/

backend.py

@@ -11,9 +11,11 @@ Erweiterte Version von Freifunk Pinneberg
 
 """
 import argparse
+import configparser
 import json
 import os
 import sys
+import logging, logging.handlers
 from datetime import datetime
 
 import networkx as nx
@@ -29,6 +31,18 @@ from lib.validate import validate_nodeinfos
 NODES_VERSION = 1
 GRAPH_VERSION = 1
 
+cfg = {
+    'cfgfile': '/etc/ffmap/ffmap-test.cfg',
+    'logfile': '/var/log/ffmap.log',
+    'loglevel': 5,
+    'dest_dir': '/var/lib/ffmap/mapdata',
+    'aliases': [],
+    'prune': 0,
+    'nodedb': '/var/lib/ffmap/nodedb',
+    'rrd_data': False,
+    'rrd_graphs': False,
+    'redis': False
+}
 
 def main(params):
     os.makedirs(params['dest_dir'], exist_ok=True)
@@ -67,7 +81,7 @@ def main(params):
     try:
         with open(nodes_fn, 'r') as nodedb_handle:
             nodedb = json.load(nodedb_handle)
-    except IOError:
+    except (IOError, ValueError):
         nodedb = {'nodes': dict()}
 
     # flush nodedb if it uses the old format
@@ -171,6 +185,19 @@ def main(params):
         if params['img']:
             rrd.update_images()
 
+def set_loglevel(nr):
+    """
+    Umsetzen der Nummer auf einen für "logging" passenden Wert
+    Die Nummer kann ein Wert zwischen 0 - kein Logging und 5 - Debug sein
+    """
+    level = (None, logging.CRITICAL, logging.ERROR, logging.WARNING,
+             logging.INFO, logging.DEBUG)
+    if nr > 5:
+        nr = 5
+    elif nr < 0:
+        nr = 0
+    return level[nr]
+
 if __name__ == '__main__':
 
     # get options from command line
@@ -188,7 +215,9 @@ if __name__ == '__main__':
                              'bat0:/run/alfred0.sock.')
     parser.add_argument('-d', '--dest-dir', action='store',
                         help='Write output to destination directory',
-                        required=True)
+                        required=False)
+    parser.add_argument('-c', '--config', action='store', metavar='FILE',
+                        help='read configuration from FILE')
     parser.add_argument('-V', '--vpn', nargs='+', metavar='MAC',
                         help='Assume MAC addresses are part of vpn')
     parser.add_argument('-p', '--prune', metavar='DAYS', type=int,
@@ -204,4 +233,37 @@ if __name__ == '__main__':
                              'intensive)')
 
     options = vars(parser.parse_args())
+    if options['config']:
+        cfg['cfgfile'] = options['config']
+
+    config = configparser.ConfigParser(cfg)
+    if config.read(cfg['cfgfile']):
+        if not options['nodedb']:
+            options['nodedb'] = config.get('rrd', 'nodedb')
+        if not options['dest_dir']:
+            options['dest_dir'] = config.get('global', 'dest_dir')
+        if not options['rrd']:
+            options['rrd'] = config.getboolean('rrd', 'enabled')
+        if not options['img']:
+            options['img'] = config.getboolean('rrd', 'graphs')
+        cfg['logfile'] = config.get('global', 'logfile')
+        cfg['loglevel'] = config.getint('global', 'loglevel')
+
+    # At this point global configuration is available. Time to enable logging
+    # Logging is handled by the operating system, so use WatchedFileHandler
+    handler = logging.handlers.WatchedFileHandler(cfg['logfile'])
+    handler.setFormatter(logging.Formatter(fmt='%(asctime)s %(levelname)s %(message)s',
+                                           datefmt='%Y-%m-%d %H:%M:%S'))
+    log = logging.getLogger()
+    log.addHandler(handler)
+    loglevel = set_loglevel(cfg['loglevel'])
+    if loglevel:
+        log.setLevel(loglevel)
+    else:
+        log.disabled = True
+
+    log.info("%s started" % sys.argv[0])
+    if os.path.isfile(cfg['cfgfile']):
+        log.info("using configuration from '%s'" % cfg['cfgfile'])
     main(options)
+    log.info("%s finished" % sys.argv[0])