Synnefo » snf-ganeti

#!/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.

"""Ganeti node daemon"""

# functions in this module need to have a given name structure, so:

# pylint: disable-msg=C0103

import os

import sys

import resource

import traceback

from optparse import OptionParser

from ganeti import backend

from ganeti import logger

from ganeti import constants

from ganeti import objects

from ganeti import errors

from ganeti import ssconf

from twisted.spread import pb

from twisted.internet import reactor

from twisted.cred import checkers, portal

from OpenSSL import SSL

class ServerContextFactory:

  """SSL context factory class that uses a given certificate.

  """

  @staticmethod

  def getContext():

    """Return a customized context.

    The context will be set to use our certificate.

    """

    ctx = SSL.Context(SSL.TLSv1_METHOD)

    ctx.use_certificate_file(constants.SSL_CERT_FILE)

    ctx.use_privatekey_file(constants.SSL_CERT_FILE)

    return ctx

class ServerObject(pb.Avatar):

  """The server implementation.

  This class holds all methods exposed over the RPC interface.

  """

  def __init__(self, name):

    self.name = name

  def perspectiveMessageReceived(self, broker, message, args, kw):

    """Custom message dispatching function.

    This function overrides the pb.Avatar function in order to provide

    a simple form of exception passing (as text only).

    """

    args = broker.unserialize(args, self)

    kw = broker.unserialize(kw, self)

    method = getattr(self, "perspective_%s" % message)

    tb = None

    state = None

    try:

      state = method(*args, **kw)

    except:

      tb = traceback.format_exc()

    return broker.serialize((tb, state), self, method, args, kw)

  # the new block devices  --------------------------

  @staticmethod

  def perspective_blockdev_create(params):

    """Create a block device.

    """

    bdev_s, size, on_primary, info = params

    bdev = objects.ConfigObject.Loads(bdev_s)

    if bdev is None:

      raise ValueError("can't unserialize data!")

    return backend.CreateBlockDevice(bdev, size, on_primary, info)

  @staticmethod

  def perspective_blockdev_remove(params):

    """Remove a block device.

    """

    bdev_s = params[0]

    bdev = objects.ConfigObject.Loads(bdev_s)

    return backend.RemoveBlockDevice(bdev)

  @staticmethod

  def perspective_blockdev_assemble(params):

    """Assemble a block device.

    """

    bdev_s, on_primary = params

    bdev = objects.ConfigObject.Loads(bdev_s)

    if bdev is None:

      raise ValueError("can't unserialize data!")

    return backend.AssembleBlockDevice(bdev, on_primary)

  @staticmethod

  def perspective_blockdev_shutdown(params):

    """Shutdown a block device.

    """

    bdev_s = params[0]

    bdev = objects.ConfigObject.Loads(bdev_s)

    if bdev is None:

      raise ValueError("can't unserialize data!")

    return backend.ShutdownBlockDevice(bdev)

  @staticmethod

  def perspective_blockdev_addchild(params):

    """Add a child to a mirror device.

    Note: this is only valid for mirror devices. It's the caller's duty

    to send a correct disk, otherwise we raise an error.

    """

    bdev_s, ndev_s = params

    bdev = objects.ConfigObject.Loads(bdev_s)

    ndev = objects.ConfigObject.Loads(ndev_s)

    if bdev is None or ndev is None:

      raise ValueError("can't unserialize data!")

    return backend.MirrorAddChild(bdev, ndev)

  @staticmethod

  def perspective_blockdev_removechild(params):

    """Remove a child from a mirror device.

    This is only valid for mirror devices, of course. It's the callers

    duty to send a correct disk, otherwise we raise an error.

    """

    bdev_s, ndev_s = params

    bdev = objects.ConfigObject.Loads(bdev_s)

    ndev = objects.ConfigObject.Loads(ndev_s)

    if bdev is None or ndev is None:

      raise ValueError("can't unserialize data!")

    return backend.MirrorRemoveChild(bdev, ndev)

  @staticmethod

  def perspective_blockdev_getmirrorstatus(params):

    """Return the mirror status for a list of disks.

    """

    disks = [objects.ConfigObject.Loads(dsk_s)

            for dsk_s in params]

    return backend.GetMirrorStatus(disks)

  @staticmethod

  def perspective_blockdev_find(params):

    """Expose the FindBlockDevice functionality for a disk.

    This will try to find but not activate a disk.

    """

    disk = objects.ConfigObject.Loads(params[0])

    return backend.FindBlockDevice(disk)

  @staticmethod

  def perspective_blockdev_snapshot(params):

    """Create a snapshot device.

    Note that this is only valid for LVM disks, if we get passed

    something else we raise an exception. The snapshot device can be

    remove by calling the generic block device remove call.

    """

    cfbd = objects.ConfigObject.Loads(params[0])

    return backend.SnapshotBlockDevice(cfbd)

  # export/import  --------------------------

  @staticmethod

  def perspective_snapshot_export(params):

    """Export a given snapshot.

    """

    disk = objects.ConfigObject.Loads(params[0])

    dest_node = params[1]

    instance = objects.ConfigObject.Loads(params[2])

    return backend.ExportSnapshot(disk, dest_node, instance)

  @staticmethod

  def perspective_finalize_export(params):

    """Expose the finalize export functionality.

    """

    instance = objects.ConfigObject.Loads(params[0])

    snap_disks = [objects.ConfigObject.Loads(str_data)

                  for str_data in params[1]]

    return backend.FinalizeExport(instance, snap_disks)

  @staticmethod

  def perspective_export_info(params):

    """Query information about an existing export on this node.

    The given path may not contain an export, in which case we return

    None.

    """

    path = params[0]

    einfo = backend.ExportInfo(path)

    if einfo is None:

      return einfo

    return einfo.Dumps()

  @staticmethod

  def perspective_export_list(params):

    """List the available exports on this node.

    Note that as opposed to export_info, which may query data about an

    export in any path, this only queries the standard Ganeti path

    (constants.EXPORT_DIR).

    """

    return backend.ListExports()

  @staticmethod

  def perspective_export_remove(params):

    """Remove an export.

    """

    export = params[0]

    return backend.RemoveExport(export)

  # volume  --------------------------

  @staticmethod

  def perspective_volume_list(params):

    """Query the list of logical volumes in a given volume group.

    """

    vgname = params[0]

    return backend.GetVolumeList(vgname)

  @staticmethod

  def perspective_vg_list(params):

    """Query the list of volume groups.

    """

    return backend.ListVolumeGroups()

  # bridge  --------------------------

  @staticmethod

  def perspective_bridges_exist(params):

    """Check if all bridges given exist on this node.

    """

    bridges_list = params[0]

    return backend.BridgesExist(bridges_list)

  # instance  --------------------------

  @staticmethod

  def perspective_instance_os_add(params):

    """Install an OS on a given instance.

    """

    inst_s, os_disk, swap_disk = params

    inst = objects.ConfigObject.Loads(inst_s)

    return backend.AddOSToInstance(inst, os_disk, swap_disk)

  @staticmethod

  def perspective_instance_os_import(params):

    """Run the import function of an OS onto a given instance.

    """

    inst_s, os_disk, swap_disk, src_node, src_image = params

    inst = objects.ConfigObject.Loads(inst_s)

    return backend.ImportOSIntoInstance(inst, os_disk, swap_disk,

                                        src_node, src_image)

  @staticmethod

  def perspective_instance_shutdown(params):

    """Shutdown an instance.

    """

    instance = objects.ConfigObject.Loads(params[0])

    return backend.ShutdownInstance(instance)

  @staticmethod

  def perspective_instance_start(params):

    """Start an instance.

    """

    instance = objects.ConfigObject.Loads(params[0])

    extra_args = params[1]

    return backend.StartInstance(instance, extra_args)

  @staticmethod

  def perspective_instance_info(params):

    """Query instance information.

    """

    return backend.GetInstanceInfo(params[0])

  @staticmethod

  def perspective_all_instances_info(params):

    """Query information about all instances.

    """

    return backend.GetAllInstancesInfo()

  @staticmethod

  def perspective_instance_list(params):

    """Query the list of running instances.

    """

    return backend.GetInstanceList()

  # node --------------------------

  @staticmethod

  def perspective_node_info(params):

    """Query node information.

    """

    vgname = params[0]

    return backend.GetNodeInfo(vgname)

  @staticmethod

  def perspective_node_add(params):

    """Complete the registration of this node in the cluster.

    """

    return backend.AddNode(params[0], params[1], params[2],

                           params[3], params[4], params[5])

  @staticmethod

  def perspective_node_verify(params):

    """Run a verify sequence on this node.

    """

    return backend.VerifyNode(params[0])

  @staticmethod

  def perspective_node_start_master(params):

    """Promote this node to master status.

    """

    return backend.StartMaster()

  @staticmethod

  def perspective_node_stop_master(params):

    """Demote this node from master status.

    """

    return backend.StopMaster()

  @staticmethod

  def perspective_node_leave_cluster(params):

    """Cleanup after leaving a cluster.

    """

    return backend.LeaveCluster()

  @staticmethod

  def perspective_node_volumes(params):

    """Query the list of all logical volume groups.

    """

    return backend.NodeVolumes()

  # cluster --------------------------

  @staticmethod

  def perspective_version(params):

    """Query version information.

    """

    return constants.PROTOCOL_VERSION

  @staticmethod

  def perspective_upload_file(params):

    """Upload a file.

    Note that the backend implementation imposes strict rules on which

    files are accepted.

    """

    return backend.UploadFile(*params)

  # os -----------------------

  @staticmethod

  def perspective_os_diagnose(params):

    """Query detailed information about existing OSes.

    """

    os_list = backend.DiagnoseOS()

    if not os_list:

      # this catches also return values of 'False',

      # for which we can't iterate over

      return os_list

    result = []

    for data in os_list:

      if isinstance(data, objects.OS):

        result.append(data.Dumps())

      elif isinstance(data, errors.InvalidOS):

        result.append(data.args)

      else:

        raise errors.ProgrammerError("Invalid result from backend.DiagnoseOS"

                                     " (class %s, %s)" %

                                     (str(data.__class__), data))

    return result

  @staticmethod

  def perspective_os_get(params):

    """Query information about a given OS.

    """

    name = params[0]

    try:

      os_obj = backend.OSFromDisk(name).Dumps()

    except errors.InvalidOS, err:

      os_obj = err.args

    return os_obj

  # hooks -----------------------

  @staticmethod

  def perspective_hooks_runner(params):

    """Run hook scripts.

    """

    hpath, phase, env = params

    hr = backend.HooksRunner()

    return hr.RunHooks(hpath, phase, env)

class MyRealm:

  """Simple realm that forwards all requests to a ServerObject.

  """

  __implements__ = portal.IRealm

  def requestAvatar(self, avatarId, mind, *interfaces):

    """Return an avatar based on our ServerObject class.

    """

    if pb.IPerspective not in interfaces:

      raise NotImplementedError

    return pb.IPerspective, ServerObject(avatarId), lambda:None

def ParseOptions():

  """Parse the command line options.

  Returns:

    (options, args) as from OptionParser.parse_args()

  """

  parser = OptionParser(description="Ganeti node daemon",

                        usage="%prog [-f] [-d]",

                        version="%%prog (ganeti) %s" %

                        constants.RELEASE_VERSION)

  parser.add_option("-f", "--foreground", dest="fork",

                    help="Don't detach from the current terminal",

                    default=True, action="store_false")

  parser.add_option("-d", "--debug", dest="debug",

                    help="Enable some debug messages",

                    default=False, action="store_true")

  options, args = parser.parse_args()

  return options, args

def main():

  """Main function for the node daemon.

  """

  options, args = ParseOptions()

  for fname in (constants.SSL_CERT_FILE,):

    if not os.path.isfile(fname):

      print "config %s not there, will not run." % fname

      sys.exit(5)

  try:

    ss = ssconf.SimpleStore()

    port = ss.GetNodeDaemonPort()

    pwdata = ss.GetNodeDaemonPassword()

  except errors.ConfigurationError, err:

    print "Cluster configuration incomplete: '%s'" % str(err)

    sys.exit(5)

  # become a daemon

  if options.fork:

    createDaemon()

  logger.SetupLogging(twisted_workaround=True, debug=options.debug,

                      program="ganeti-noded")

  p = portal.Portal(MyRealm())

  p.registerChecker(

    checkers.InMemoryUsernamePasswordDatabaseDontUse(master_node=pwdata))

  reactor.listenSSL(port, pb.PBServerFactory(p), ServerContextFactory())

  reactor.run()

def createDaemon():

  """Detach a process from the controlling terminal and run it in the

  background as a daemon.

  """

  UMASK = 077

  WORKDIR = "/"

  # Default maximum for the number of available file descriptors.

  if 'SC_OPEN_MAX' in os.sysconf_names:

    try:

      MAXFD = os.sysconf('SC_OPEN_MAX')

      if MAXFD < 0:

        MAXFD = 1024

    except OSError:

      MAXFD = 1024

  else:

    MAXFD = 1024

  # The standard I/O file descriptors are redirected to /dev/null by default.

  #REDIRECT_TO = getattr(os, "devnull", "/dev/null")

  REDIRECT_TO = constants.LOG_NODESERVER

  try:

    pid = os.fork()

  except OSError, e:

    raise Exception("%s [%d]" % (e.strerror, e.errno))

  if (pid == 0):  # The first child.

    os.setsid()

    try:

      pid = os.fork() # Fork a second child.

    except OSError, e:

      raise Exception("%s [%d]" % (e.strerror, e.errno))

    if (pid == 0):  # The second child.

      os.chdir(WORKDIR)

      os.umask(UMASK)

    else:

      # exit() or _exit()?  See below.

      os._exit(0) # Exit parent (the first child) of the second child.

  else:

    os._exit(0) # Exit parent of the first child.

  maxfd = resource.getrlimit(resource.RLIMIT_NOFILE)[1]

  if (maxfd == resource.RLIM_INFINITY):

    maxfd = MAXFD

  # Iterate through and close all file descriptors.

  for fd in range(0, maxfd):

    try:

      os.close(fd)

    except OSError: # ERROR, fd wasn't open to begin with (ignored)

      pass

  os.open(REDIRECT_TO, os.O_RDWR|os.O_CREAT|os.O_APPEND) # standard input (0)

  # Duplicate standard input to standard output and standard error.

  os.dup2(0, 1)     # standard output (1)

  os.dup2(0, 2)     # standard error (2)

  return(0)

if __name__ == '__main__':

  main()