add basic config module

Signed-off-by: NMark Hymers <mhy@debian.org>

daklib/Config.py

+#!/usr/bin/env python
+
+# Config access class
+# Copyright (C) 2008  Mark Hymers <mhy@debian.org>
+
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 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 General Public License for more details.
+
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+################################################################################
+
+# <NCommander> mhy, how about "Now with 20% more monty python references"
+
+################################################################################
+
+import apt_pkg
+import socket
+
+from Singleton import Singleton
+
+################################################################################
+
+default_config = "/etc/dak/dak.conf"
+
+def which_conf_file(Cnf):
+    res = socket.gethostbyaddr(socket.gethostname())
+    if Cnf.get("Config::" + res[0] + "::DakConfig"):
+        return Cnf["Config::" + res[0] + "::DakConfig"]
+    else:
+        return default_config
+
+class Config(Singleton):
+    """
+    A Config object is a singleton containing
+    information about the DAK configuration
+    """
+    def __init__(self, *args, **kwargs):
+        super(Config, self).__init__(*args, **kwargs)
+
+    def _readconf(self):
+        apt_pkg.init()
+
+        self.Cnf = apt_pkg.newConfiguration()
+
+        apt_pkg.ReadConfigFileISC(self.Cnf, default_config)
+
+        # Check whether our dak.conf was the real one or
+        # just a pointer to our main one
+        res = socket.gethostbyaddr(socket.gethostname())
+        conffile = self.Cnf.get("Config::" + res[0] + "::DakConfig")
+        if conffile:
+            apt_pkg.ReadConfigFileISC(self.Cnf, conffile)
+
+        # Rebind some functions
+        # TODO: Clean this up
+        self.get = self.Cnf.get
+        self.SubTree = self.Cnf.SubTree
+        self.ValueList = self.Cnf.ValueList
+
+    def _startup(self, *args, **kwargs):
+        self._readconf()
+
+    def __getitem__(self, name):
+        return self.Cnf[name]
+
+    def GetDBConnString(self):
+        s = "dbname=%s" % self.Cnf["DB::Name"]
+        if self.Cnf["DB::Host"]:
+            s += " host=%s" % self.Cnf["DB::Host"]
+        if self.Cnf["DB::Port"] and self.Cnf["DB::Port"] != "-1":
+            s += " port=%s" % self.Cnf["DB::Port"]
+
+        return s