diff -r f4956b4ceba1 -r 011066435e6f VirtualMailManager/cli/config.py
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/VirtualMailManager/cli/config.py	Wed Jul 28 02:08:03 2010 +0000
@@ -0,0 +1,93 @@
+# -*- coding: UTF-8 -*-
+# Copyright (c) 2010, Pascal Volk
+# See COPYING for distribution information.
+"""
+    VirtualMailManager.cli.config
+    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+    Adds some interactive stuff to the Config class.
+"""
+
+from ConfigParser import RawConfigParser
+from shutil import copy2
+
+from VirtualMailManager import ENCODING
+from VirtualMailManager.config import Config, ConfigValueError, LazyConfig
+from VirtualMailManager.errors import ConfigError
+from VirtualMailManager.cli import w_err, w_std
+from VirtualMailManager.constants import VMM_TOO_MANY_FAILURES
+
+_ = lambda msg: msg
+
+
+class CliConfig(Config):
+    """Adds the interactive ``configure`` method to the `Config` class
+    and overwrites `LazyConfig.set(), in order to update a single option
+    in the configuration file with a single command line command.
+    """
+
+    def configure(self, sections):
+        """Interactive method for configuring all options of the given
+        iterable ``sections`` object."""
+        input_fmt = _(u'Enter new value for option %(option)s '
+                      u'[%(current_value)s]: ')
+        failures = 0
+
+        w_std(_(u'Using configuration file: %s\n') % self._cfg_filename)
+        for section in sections:
+            w_std(_(u'* Configuration section: %r') % section)
+            for opt, val in self.items(section):
+                failures = 0
+                while True:
+                    newval = raw_input(input_fmt.encode(ENCODING, 'replace') %
+                                       {'option': opt, 'current_value': val})
+                    if newval and newval != val:
+                        try:
+                            LazyConfig.set(self, '%s.%s' % (section, opt),
+                                           newval)
+                            break
+                        except (ValueError, ConfigValueError), err:
+                            w_err(0, _(u'Warning: %s') % err)
+                            failures += 1
+                            if failures > 2:
+                                raise ConfigError(_(u'Too many failures - try '
+                                                    u'again later.'),
+                                                  VMM_TOO_MANY_FAILURES)
+                    else:
+                        break
+            print
+        if self._modified:
+            self.__save_changes()
+
+    def set(self, option, value):
+        """Set the value of an option.
+
+        If the new `value` has been set, the configuration file will be
+        immediately updated.
+
+        Throws a ``ValueError`` if `value` couldn't be converted to
+        ``LazyConfigOption.cls``"""
+        section, option_ = self._get_section_option(option)
+        val = self._cfg[section][option_].cls(value)
+        if self._cfg[section][option_].validate:
+            val = self._cfg[section][option_].validate(val)
+        # Do not write default values also skip identical values
+        if not self._cfg[section][option_].default is None:
+            old_val = self.dget(option)
+        else:
+            old_val = self.pget(option)
+        if val == old_val:
+            return
+        if not RawConfigParser.has_section(self, section):
+            self.add_section(section)
+        RawConfigParser.set(self, section, option_, val)
+        self.__save_changes()
+
+    def __save_changes(self):
+        """Writes changes to the configuration file."""
+        copy2(self._cfg_filename, self._cfg_filename + '.bak')
+        self._cfg_file = open(self._cfg_filename, 'w')
+        self.write(self._cfg_file)
+        self._cfg_file.close()
+
+del _