'Set up conditional defaults and check for dependencies.
If SSL is not available but an HTTPS server was configured, raise a
L{UsageError} indicating that this is not possible.
If no server port was supplied, select a default appropriate for the
other options supplied.'

def postOptions(self):

    if self['https']:
        try:
            reflect.namedModule('OpenSSL.SSL')
        except ImportError:
            raise usage.UsageError('SSL    support    not    installed')
    if (self['port'] is None):
        if self['personal']:
            path = os.path.expanduser(os.path.join('~', distrib.UserDirectory.userSocketName))
            self['port'] = ('unix:' + path)
        else:
            self['port'] = 'tcp:8080'
