#!/usr/bin/python
#

# Copyright (C) 2006, 2007 Google Inc.
#
# 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., 51 Franklin Street, Fifth Floor, Boston, MA
# 02110-1301, USA.


"""Burnin program

"""

import os
import sys
import optparse
from itertools import izip, islice, cycle
from cStringIO import StringIO

from ganeti import opcodes
from ganeti import mcpu
from ganeti import constants
from ganeti import cli
from ganeti import logger
from ganeti import errors
from ganeti import utils


USAGE = ("\tburnin -o OS_NAME [options...] instance_name ...")


def Usage():
  """Shows program usage information and exits the program."""

  print >> sys.stderr, "Usage:"
  print >> sys.stderr, USAGE
  sys.exit(2)


def Log(msg):
  """Simple function that prints out its argument.

  """
  print msg
  sys.stdout.flush()


class Burner(object):
  """Burner class."""

  def __init__(self):
    """Constructor."""
    logger.SetupLogging(debug=False, program="ganeti/burnin")
    self._feed_buf = StringIO()
    self.proc = mcpu.Processor(feedback=self.Feedback)
    self.nodes = []
    self.instances = []
    self.to_rem = []
    self.opts = None
    self.ParseOptions()
    self.GetState()

  def ClearFeedbackBuf(self):
    """Clear the feedback buffer."""
    self._feed_buf.truncate(0)

  def GetFeedbackBuf(self):
    """Return the contents of the buffer."""
    return self._feed_buf.getvalue()

  def Feedback(self, msg):
    """Acumulate feedback in our buffer."""
    self._feed_buf.write(msg)
    self._feed_buf.write("\n")
    if self.opts.verbose:
      Log(msg)

  def ExecOp(self, op):
    """Execute an opcode and manage the exec buffer."""
    self.ClearFeedbackBuf()
    return self.proc.ExecOpCode(op)

  def ParseOptions(self):
    """Parses the command line options.

    In case of command line errors, it will show the usage and exit the
    program.

    """

    parser = optparse.OptionParser(usage="\n%s" % USAGE,
                                   version="%%prog (ganeti) %s" %
                                   constants.RELEASE_VERSION,
                                   option_class=cli.CliOption)

    parser.add_option("-o", "--os", dest="os", default=None,
                      help="OS to use during burnin",
                      metavar="<OS>")
    parser.add_option("--os-size", dest="os_size", help="Disk size",
                      default=4 * 1024, type="unit", metavar="<size>")
    parser.add_option("--swap-size", dest="swap_size", help="Swap size",
                      default=4 * 1024, type="unit", metavar="<size>")
    parser.add_option("-v", "--verbose",
                      action="store_true", dest="verbose", default=False,
                      help="print command execution messages to stdout")
    parser.add_option("--no-replace1", dest="do_replace1",
                      help="Skip disk replacement with the same secondary",
                      action="store_false", default=True)
    parser.add_option("--no-replace2", dest="do_replace2",
                      help="Skip disk replacement with a different secondary",
                      action="store_false", default=True)
    parser.add_option("--no-failover", dest="do_failover",
                      help="Skip instance failovers", action="store_false",
                      default=True)
    parser.add_option("--no-importexport", dest="do_importexport",
                      help="Skip instance export/import", action="store_false",
                      default=True)
    parser.add_option("--no-startstop", dest="do_startstop",
                      help="Skip instance stop/start", action="store_false",
                      default=True)
    parser.add_option("-t", "--disk-template", dest="disk_template",
                      choices=("diskless", "plain", "remote_raid1", "drbd"),
                      default="remote_raid1",
                      help="Template type for network mirroring (remote_raid1"
                      " or drbd) [remote_raid1]")
    parser.add_option("-n", "--nodes", dest="nodes", default="",
                      help="Comma separated list of nodes to perform"
                      " the burnin on (defaults to all nodes)")

    options, args = parser.parse_args()
    if len(args) < 1 or options.os is None:
      Usage()

    supported_disk_templates = (constants.DT_DISKLESS, constants.DT_PLAIN,
                                constants.DT_REMOTE_RAID1,
                                constants.DT_DRBD8)
    if options.disk_template not in supported_disk_templates:
      Log("Unknown disk template '%s'" % options.disk_template)
      sys.exit(1)

    self.opts = options
    self.instances = args

  def GetState(self):
    """Read the cluster state from the config."""
    if self.opts.nodes:
      names = self.opts.nodes.split(",")
    else:
      names = []
    try:
      op = opcodes.OpQueryNodes(output_fields=["name"], names=names)
      result = self.ExecOp(op)
    except errors.GenericError, err:
      err_code, msg = cli.FormatError(err)
      Log(msg)
      sys.exit(err_code)
    self.nodes = [data[0] for data in result]

    result = self.ExecOp(opcodes.OpDiagnoseOS())

    if not result:
      Log("Can't get the OS list")
      sys.exit(1)

    # filter non-valid OS-es
    oses = {}
    for node_name in result:
      oses[node_name] = [obj for obj in result[node_name] if obj]

    fnode = oses.keys()[0]
    os_set = set([os_inst.name for os_inst in oses[fnode]])
    del oses[fnode]
    for node in oses:
      os_set &= set([os_inst.name for os_inst in oses[node]])

    if self.opts.os not in os_set:
      Log("OS '%s' not found" % self.opts.os)
      sys.exit(1)

  def CreateInstances(self):
    """Create the given instances.

    """
    self.to_rem = []
    mytor = izip(cycle(self.nodes),
                 islice(cycle(self.nodes), 1, None),
                 self.instances)
    for pnode, snode, instance in mytor:
      op = opcodes.OpCreateInstance(instance_name=instance,
                                    mem_size=128,
                                    disk_size=self.opts.os_size,
                                    swap_size=self.opts.swap_size,
                                    disk_template=self.opts.disk_template,
                                    mode=constants.INSTANCE_CREATE,
                                    os_type=self.opts.os,
                                    pnode=pnode,
                                    snode=snode,
                                    vcpus=1,
                                    start=True,
                                    ip_check=True,
                                    wait_for_sync=True,
                                    mac="auto",
                                    kernel_path=None,
                                    initrd_path=None,
                                    hvm_boot_order=None)
      Log("- Add instance %s on nodes %s/%s" % (instance, pnode, snode))
      self.ExecOp(op)
      self.to_rem.append(instance)

  def ReplaceDisks1R1(self):
    """Replace disks with the same secondary for rr1."""
    # replace all, both disks
    for instance in self.instances:
      op = opcodes.OpReplaceDisks(instance_name=instance,
                                  remote_node=None,
                                  mode=constants.REPLACE_DISK_ALL,
                                  disks=["sda", "sdb"])

      Log("- Replace disks for instance %s" % (instance))
      self.ExecOp(op)

  def ReplaceDisks1D8(self):
    """Replace disks on primary and secondary for drbd8."""
    for instance in self.instances:
      for mode in constants.REPLACE_DISK_SEC, constants.REPLACE_DISK_PRI:
        op = opcodes.OpReplaceDisks(instance_name=instance,
                                    mode=mode,
                                    disks=["sda", "sdb"])
        Log("- Replace disks (%s) for instance %s" % (mode, instance))
        self.ExecOp(op)

  def ReplaceDisks2(self):
    """Replace secondary node."""
    if self.opts.disk_template == constants.DT_REMOTE_RAID1:
      mode = constants.REPLACE_DISK_ALL
    else:
      mode = constants.REPLACE_DISK_SEC

    mytor = izip(islice(cycle(self.nodes), 2, None),
                 self.instances)
    for tnode, instance in mytor:
      op = opcodes.OpReplaceDisks(instance_name=instance,
                                  mode=mode,
                                  remote_node=tnode,
                                  disks=["sda", "sdb"])
      Log("- Replace secondary (%s) for instance %s" % (mode, instance))
      self.ExecOp(op)

  def Failover(self):
    """Failover the instances."""

    for instance in self.instances:
      op = opcodes.OpFailoverInstance(instance_name=instance,
                                      ignore_consistency=False)

      Log("- Failover instance %s" % (instance))
      self.ExecOp(op)

  def ImportExport(self):
    """Export the instance, delete it, and import it back.

    """

    mytor = izip(cycle(self.nodes),
                 islice(cycle(self.nodes), 1, None),
                 islice(cycle(self.nodes), 2, None),
                 self.instances)

    for pnode, snode, enode, instance in mytor:
      exp_op = opcodes.OpExportInstance(instance_name=instance,
                                           target_node=enode,
                                           shutdown=True)
      rem_op = opcodes.OpRemoveInstance(instance_name=instance)
      nam_op = opcodes.OpQueryInstances(output_fields=["name"],
                                           names=[instance])
      full_name = self.ExecOp(nam_op)[0][0]
      imp_dir = os.path.join(constants.EXPORT_DIR, full_name)
      imp_op = opcodes.OpCreateInstance(instance_name=instance,
                                        mem_size=128,
                                        disk_size=self.opts.os_size,
                                        swap_size=self.opts.swap_size,
                                        disk_template=self.opts.disk_template,
                                        mode=constants.INSTANCE_IMPORT,
                                        src_node=enode,
                                        src_path=imp_dir,
                                        pnode=pnode,
                                        snode=snode,
                                        vcpus=1,
                                        start=True,
                                        ip_check=True,
                                        wait_for_sync=True,
                                        mac="auto")

      Log("- Export instance %s to node %s" % (instance, enode))
      self.ExecOp(exp_op)
      Log("- Remove instance %s" % (instance))
      self.ExecOp(rem_op)
      self.to_rem.remove(instance)
      Log("- Import instance %s from node %s to node %s" %
          (instance, enode, pnode))
      self.ExecOp(imp_op)
      self.to_rem.append(instance)

  def StopStart(self):
    """Stop/start the instances."""
    for instance in self.instances:
      op = opcodes.OpShutdownInstance(instance_name=instance)
      Log("- Shutdown instance %s" % instance)
      self.ExecOp(op)
      op = opcodes.OpStartupInstance(instance_name=instance, force=False)
      Log("- Start instance %s" % instance)
      self.ExecOp(op)

  def Remove(self):
    """Remove the instances."""
    for instance in self.to_rem:
      op = opcodes.OpRemoveInstance(instance_name=instance)
      Log("- Remove instance %s" % instance)
      self.ExecOp(op)

  def BurninCluster(self):
    """Test a cluster intensively.

    This will create instances and then start/stop/failover them.
    It is safe for existing instances but could impact performance.

    """

    opts = self.opts

    Log("- Testing global parameters")

    if (len(self.nodes) == 1 and
        opts.disk_template not in (constants.DT_DISKLESS, constants.DT_PLAIN)):
      Log("When one node is available/selected the disk template must"
               " be 'plain' or 'diskless'")
      sys.exit(1)

    has_err = True
    try:
      self.CreateInstances()
      if opts.do_replace1 and opts.disk_template in constants.DTS_NET_MIRROR:
        if opts.disk_template == constants.DT_REMOTE_RAID1:
          self.ReplaceDisks1R1()
        elif opts.disk_template == constants.DT_DRBD8:
          self.ReplaceDisks1D8()
      if (opts.do_replace2 and len(self.nodes) > 2 and
          opts.disk_template in constants.DTS_NET_MIRROR) :
        self.ReplaceDisks2()

      if opts.do_failover and opts.disk_template in constants.DTS_NET_MIRROR:
        self.Failover()

      if opts.do_importexport:
        self.ImportExport()

      if opts.do_startstop:
        self.StopStart()

      has_err = False
    finally:
      if has_err:
        Log("Error detected: opcode buffer follows:\n\n")
        Log(self.GetFeedbackBuf())
        Log("\n\n")
      self.Remove()

    return 0


def main():
  """Main function"""

  burner = Burner()
  try:
    utils.Lock('cmd', max_retries=15, debug=True)
  except errors.LockError, err:
    logger.ToStderr(str(err))
    return 1
  try:
    retval = burner.BurninCluster()
  finally:
    utils.Unlock('cmd')
    utils.LockCleanup()
  return retval


if __name__ == "__main__":
  main()