#!/usr/bin/env python
#
#  Copyright (C) 2002 Cluster File Systems, Inc.
#   Author: Robert Read <rread@clusterfs.com>
#   This file is part of Lustre, http://www.lustre.org.
#
#   Lustre is free software; you can redistribute it and/or
#   modify it under the terms of version 2 of the GNU General Public
#   License as published by the Free Software Foundation.
#
#   Lustre 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 Lustre; if not, write to the Free Software
#   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
#

# For all the OST/MDSs that are primary on the --primary node, set
# them to be active on --active if that OST is available on --active.
#
# Make the active node the active node for all devices it shares with the
# old. The bulk of this code is for figuring out which devices to
# change, and what to change them to.

# XXX add error checking
# XXX make this code less ugly

import sys, getopt, types
import string, os
import ldap
from stat import S_IROTH, S_IRGRP
PYMOD_DIR = "/usr/lib/lustre/python"

def development_mode():
    base = os.path.dirname(sys.argv[0])
    if os.access(base+"/Makefile.am", os.R_OK):
        return 1
    return 0

if not development_mode():
    sys.path.append(PYMOD_DIR)

import Lustre
PARAM = Lustre.Options.PARAM

lactive_options = [
    ('ldapurl',"LDAP server URL", PARAM, "ldap://localhost"),
    ('config', "Cluster config name used for LDAP query", PARAM),
    ('group', "The group of devices to update", PARAM),
    ('active', "The active node name", PARAM),
    ('pwfile', "File containing password", PARAM),
    ]

def fatal(*args):
    msg = string.join(map(str,args))
    print "! " + msg
    sys.exit(1)

cl = Lustre.Options("lactive","", lactive_options)
config, args = cl.parse(sys.argv[1:])

if not (config.group or config.active):
    fatal("Must specify both  group and active node.")

if not config.config:
    fatal("Missing config")

if config.pwfile:
    try:
        pwperm = os.stat(config.pwfile)[0]
        pwreadable = pwperm & (S_IRGRP | S_IROTH)
        if pwreadable:
            if pwreadable == (S_IRGRP | S_IROTH):
                readable_by = "group and others"
            elif pwreadable == S_IRGRP:
                readable_by = "group"
            else:
                readable_by = "others"
            print "WARNING: Password file %s is readable by %s" % (
                config.pwfile, readable_by)
                 
        pwfile = open(config.pwfile, "r")
        pw = string.strip(pwfile.readline())
        pwfile.close()
    except Exception, e:
        fatal("Can't read secret from pwfile %s: %s" % (config.pwfile, e))
else:
    print "no pwfile specified, binding anonymously"
    pw = ""

base = "config=%s,fs=lustre" % (config.config,)
db = Lustre.LustreDB_LDAP('', {}, base=base, pw = pw, url = config.ldapurl)

active_node = db.lookup_name(config.active)
if not active_node:
    fatal(config.active, "node not found in database.")

devices =  db.get_group(config.group)
if len(devices) < 0:
    fatal("no devices found for group", config.group)

# for all devices in group
  # lookup device in active node
  # update the active device 
for tgtuuid in devices:
    active_uuid = db.get_active_dev(tgtuuid)
    new_active_uuid = active_node.get_tgt_dev(tgtuuid)
    if active_uuid != new_active_uuid:
        print ("%s: changing active %s to %s:%s"
               % (tgtuuid, active_uuid,
                  config.active, new_active_uuid))
        db.update_active(tgtuuid, new_active_uuid)