#!/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
import time
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(constants.LOG_BURNIN, debug=False, stderr_logging=True)
    self._feed_buf = StringIO()
    self.nodes = []
    self.instances = []
    self.to_rem = []
    self.opts = None
    self.cl = cli.GetClient()
    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("%s %s\n" % (time.ctime(utils.MergeTime(msg[0])),
                                      msg[2]))
    if self.opts.verbose:
      Log(msg)

  def ExecOp(self, op):
    """Execute an opcode and manage the exec buffer."""
    self.ClearFeedbackBuf()
    return cli.SubmitOpCode(op, feedback_fn=self.Feedback, cl=self.cl)

  def ExecJobSet(self, jobs):
    """Execute a set of jobs and return once all are done.

    The method will return the list of results, if all jobs are
    successfull. Otherwise, OpExecError will be raised from within
    cli.py.

    """
    self.ClearFeedbackBuf()
    job_ids = [cli.SendJob(job, cl=self.cl) for job in jobs]
    Log("- Submitted job IDs %s" % ", ".join(job_ids))
    results = []
    for jid in job_ids:
      Log("- Waiting for job %s" % jid)
      results.append(cli.PollJob(jid, cl=self.cl, feedback_fn=self.Feedback))

    return results

  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("--os-growth", dest="sda_growth", help="Disk growth",
                      default=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("--swap-growth", dest="sdb_growth", help="Swap growth",
                      default=1024, type="unit", metavar="<size>")
    parser.add_option("--mem-size", dest="mem_size", help="Memory size",
                      default=128, 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("--rename", dest="rename", default=None,
                      help="Give one unused instance name which is taken"
                           " to start the renaming sequence",
                      metavar="<instance_name>")
    parser.add_option("-t", "--disk-template", dest="disk_template",
                      choices=("diskless", "file", "plain", "drbd"),
                      default="drbd",
                      help="Disk template (diskless, file, plain or drbd)"
                            " [drbd]")
    parser.add_option("-n", "--nodes", dest="nodes", default="",
                      help="Comma separated list of nodes to perform"
                      " the burnin on (defaults to all nodes)")
    parser.add_option("--iallocator", dest="iallocator",
                      default=None, type="string",
                      help="Perform the allocation using an iallocator"
                      " instead of fixed node spread (node restrictions no"
                      " longer apply, therefore -n/--nodes must not be used")
    parser.add_option("-p", "--parallel", default=False, action="store_true",
                      dest="parallel",
                      help="Enable parallelization of some operations in"
                      " order to speed burnin or to test granular locking")

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

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

    if options.nodes and options.iallocator:
      Log("Give either the nodes option or the iallocator option, not both")
      sys.exit(1)

    self.opts = options
    self.instances = args
    self.bep = {
      constants.BE_MEMORY: options.mem_size,
      constants.BE_VCPUS: 1,
      }
    self.hvp = {}

  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(output_fields=["name", "valid"],
                                              names=[]))

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

    # filter non-valid OS-es
    os_set = [val[0] for val in result if val[1]]

    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)
    jobset = []

    for pnode, snode, instance in mytor:
      if self.opts.iallocator:
        pnode = snode = None
        Log("- Add instance %s (iallocator: %s)" %
              (instance, self.opts.iallocator))
      elif self.opts.disk_template not in constants.DTS_NET_MIRROR:
        snode = None
        Log("- Add instance %s on node %s" % (instance, pnode))
      else:
        Log("- Add instance %s on nodes %s/%s" % (instance, pnode, snode))

      op = opcodes.OpCreateInstance(instance_name=instance,
                                    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,
                                    start=True,
                                    ip_check=True,
                                    wait_for_sync=True,
                                    mac="auto",
                                    file_driver="loop",
                                    file_storage_dir=None,
                                    iallocator=self.opts.iallocator,
                                    beparams=self.bep,
                                    hvparams=self.hvp,
                                    )

      if self.opts.parallel:
        jobset.append([op])
        # FIXME: here we should not append to to_rem uncoditionally,
        # but only when the job is successful
        self.to_rem.append(instance)
      else:
        self.ExecOp(op)
        self.to_rem.append(instance)
    if self.opts.parallel:
      self.ExecJobSet(jobset)

  def GrowDisks(self):
    """Grow both the os and the swap disks by the requested amount, if any."""
    for instance in self.instances:
      for disk in ['sda', 'sdb']:
        growth = getattr(self.opts, '%s_growth' % disk)
        if growth > 0:
          op = opcodes.OpGrowDisk(instance_name=instance, disk=disk,
                                  amount=growth, wait_for_sync=True)
          Log("- Increase %s's %s disk by %s MB" % (instance, disk, growth))
          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."""
    mode = constants.REPLACE_DISK_SEC

    mytor = izip(islice(cycle(self.nodes), 2, None),
                 self.instances)
    for tnode, instance in mytor:
      if self.opts.iallocator:
        tnode = None
      op = opcodes.OpReplaceDisks(instance_name=instance,
                                  mode=mode,
                                  remote_node=tnode,
                                  iallocator=self.opts.iallocator,
                                  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:

      if self.opts.iallocator:
        pnode = snode = None
        import_log_msg = ("- Import instance %s from node %s (iallocator: %s)" %
                          (instance, enode, self.opts.iallocator))
      elif self.opts.disk_template not in constants.DTS_NET_MIRROR:
        snode = None
        import_log_msg = ("- Import instance %s from node %s to node %s" %
                          (instance, enode, pnode))
      else:
        import_log_msg = ("- Import instance %s from node %s to nodes %s/%s" %
                          (instance, enode, pnode, snode))

      exp_op = opcodes.OpExportInstance(instance_name=instance,
                                           target_node=enode,
                                           shutdown=True)
      rem_op = opcodes.OpRemoveInstance(instance_name=instance,
                                        ignore_failures=True)
      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,
                                        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,
                                        start=True,
                                        ip_check=True,
                                        wait_for_sync=True,
                                        mac="auto",
                                        file_storage_dir=None,
                                        file_driver=None,
                                        iallocator=self.opts.iallocator,
                                        beparams=self.bep,
                                        hvparams=self.hvp,
                                        )

      erem_op = opcodes.OpRemoveExport(instance_name=instance)

      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_log_msg)
      self.ExecOp(imp_op)
      Log("- Remove export of instance %s" % (instance))
      self.ExecOp(erem_op)

      self.to_rem.append(instance)

  def StopInstance(self, instance):
    """Stop given instance."""
    op = opcodes.OpShutdownInstance(instance_name=instance)
    Log("- Shutdown instance %s" % instance)
    self.ExecOp(op)

  def StartInstance(self, instance):
    """Start given instance."""
    op = opcodes.OpStartupInstance(instance_name=instance, force=False)
    Log("- Start instance %s" % instance)
    self.ExecOp(op)

  def RenameInstance(self, instance, instance_new):
    """Rename instance."""
    op = opcodes.OpRenameInstance(instance_name=instance,
                                  new_name=instance_new)
    Log("- Rename instance %s to %s" % (instance, instance_new))
    self.ExecOp(op)

  def StopStart(self):
    """Stop/start the instances."""
    for instance in self.instances:
      self.StopInstance(instance)
      self.StartInstance(instance)

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


  def Rename(self):
    """Rename the instances."""
    rename = self.opts.rename
    for instance in self.instances:
      self.StopInstance(instance)
      self.RenameInstance(instance, rename)
      self.StartInstance(rename)
      self.StopInstance(rename)
      self.RenameInstance(rename, instance)
      self.StartInstance(instance)

  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,
                                   constants.DT_FILE)):
      Log("When one node is available/selected the disk template must"
          " be 'diskless', 'file' or 'plain'")
      sys.exit(1)

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

      if opts.disk_template != constants.DT_DISKLESS:
        self.GrowDisks()

      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()

      if opts.rename:
        self.Rename()

      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()
  return burner.BurninCluster()


if __name__ == "__main__":
  main()