code/runserver.py

   1 #!/usr/bin/env python
   2 # -*- coding: utf8 -*-
   3 """A script for starting a Breadcrumb server."""
   4
   5 # Copyright (C) 2008 Laurens Van Houtven <lvh at laurensvh.be>
   6 # This program is free software: you can redistribute it and/or modify
   7 # it under the terms of the GNU General Public License as published by
   8 # the Free Software Foundation, either version 3 of the License, or
   9 # (at your option) any later version.
  10 #
  11 # This program is distributed in the hope that it will be useful,
  12 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 # GNU General Public License for more details.
  15 #
  16 # You should have received a copy of the GNU General Public License
  17 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18
  19 import os
  20 import sys
  21 import logging
  22
  23 import optparse
  24 import ConfigParser
  25
  26 import breadcrumb.server.net as net
  27 import breadcrumb.server.handlers.base as base
  28 import breadcrumb.common.consts as consts
  29 from breadcrumb.common.loggingtools import get_logging_level
  30
  31 def main():
  32     """ Starts the default Breadcrumb server. """
  33     config = find_configuration()
  34     serverargs = get_serverargs(config)
  35
  36     if 'verbosity' in serverargs:
  37         logger.setLevel(get_logging_level(serverargs['verbosity']))
  38
  39     if 'pythonpath' in serverargs:
  40         sys.path.append(os.path.abspath(serverargs['pythonpath']))
  41         del serverargs['pythonpath']
  42
  43     handler = parse_handlers(config)
  44
  45     net.start_server(handler = handler, **serverargs)
  46
  47 def find_configuration(filename = None):
  48     """Tries to find and parse a server configuration file.
  49
  50     Returns a ConfigParser object."""
  51     config = ConfigParser.ConfigParser()
  52
  53     filenames = filter(None, consts.SERVER_CONFIG_FILENAMES + [filename])
  54     for filename in filenames:
  55         try:
  56             filename = os.path.expanduser(filename)
  57             config.readfp(open(filename))
  58             logger.info("Using config file %s..." % filename)
  59             return config
  60         except NameError:
  61             logger.debug("No config file at %s..." % filename)
  62             continue
  63
  64     logger.warning("No usable config files found!")
  65
  66 def parse_handlers(config):
  67     """Parses the handlers described in the configuration file.
  68
  69     Returns a sequential handler with all the (correctly configured) handlers
  70     from the configuration file.
  71     """
  72     seqhandler = base.SequentialHandler(name = "sequential")
  73
  74     for name in config.sections():
  75         if name == "server":
  76             continue
  77
  78         logger.debug("Found new handler section (name: %s)..." % name)
  79
  80         data = dict(config.items(name) + [['name', name]])
  81
  82         if 'class' not in data:
  83             logger.error(
  84                 'No class specified for handler section %s, skipping...' % name)
  85             continue
  86
  87         splitnames = data['class'].split('.')
  88         del data['class']
  89         modulename, classname = '.'.join(splitnames[:-1]), splitnames[-1]
  90
  91         if 'pythonpath' in data:
  92             logger.debug("Extra path specified, adding to sys.path...")
  93             sys.path.append(data['pythonpath'])
  94             del data['pythonpath']
  95
  96         try:
  97             __import__(modulename, globals(), locals(), [classname])
  98         except ImportError:
  99             logger.error("Couldn't import %s, skipping..." % modulename)
 100             continue
 101
 102         handler_class = getattr(sys.modules[modulename], classname)
 103
 104         logger.debug("Creating handler with args: %s" % repr(data))
 105         handler = handler_class(**data)
 106
 107         seqhandler.add_handler(handler)
 108
 109     return seqhandler
 110
 111 def get_serverargs(config):
 112     """Gets the server arguments from the ConfigParser object.
 113
 114     Returns a dict.
 115     """
 116     if not config.has_section('server'):
 117         logger.info("Config file doesn't have a [server] section...")
 118         return {}
 119
 120     return dict(config.items('server'))
 121
 122 if __name__ == "__main__":
 123     logging.basicConfig(level=logging.INFO)
 124     logger = logging.getLogger("Breadcrumb.Scripts.runserver")
 125     main()