Fix pylint-detected issues

[ganeti-local] / lib / rpc.py

#
#

# 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.


"""Script to show add a new node to the cluster

"""

# pylint: disable-msg=C0103

import os
import socket
import httplib

import simplejson

from ganeti import logger
from ganeti import utils
from ganeti import objects
from ganeti import ssconf


class NodeController:
  """Node-handling class.

  For each node that we speak with, we create an instance of this
  class, so that we have a safe place to store the details of this
  individual call.

  """
  def __init__(self, parent, node):
    self.parent = parent
    self.node = node
    self.failed = False

    self.http_conn = hc = httplib.HTTPConnection(node, self.parent.port)
    try:
      hc.connect()
      hc.putrequest('PUT', "/%s" % self.parent.procedure,
                    skip_accept_encoding=True)
      hc.putheader('Content-Length', str(len(parent.body)))
      hc.endheaders()
      hc.send(parent.body)
    except socket.error, err:
      logger.Error("Error connecting to %s: %s" % (node, str(err)))
      self.failed = True

  def get_response(self):
    """Try to process the response from the node.

    """
    if self.failed:
      # we already failed in connect
      return False
    resp = self.http_conn.getresponse()
    if resp.status != 200:
      return False
    try:
      length = int(resp.getheader('Content-Length', '0'))
    except ValueError:
      return False
    if not length:
      logger.Error("Zero-length reply from %s" % self.node)
      return False
    payload = resp.read(length)
    unload = simplejson.loads(payload)
    return unload


class Client:
  """RPC Client class.

  This class, given a (remote) method name, a list of parameters and a
  list of nodes, will contact (in parallel) all nodes, and return a
  dict of results (key: node name, value: result).

  One current bug is that generic failure is still signalled by
  'False' result, which is not good. This overloading of values can
  cause bugs.

  """
  result_set = False
  result = False
  allresult = []

  def __init__(self, procedure, args):
    ss = ssconf.SimpleStore()
    self.port = ss.GetNodeDaemonPort()
    self.nodepw = ss.GetNodeDaemonPassword()
    self.nc = {}
    self.results = {}
    self.procedure = procedure
    self.args = args
    self.body = simplejson.dumps(args)

  #--- generic connector -------------

  def connect_list(self, node_list):
    """Add a list of nodes to the target nodes.

    """
    for node in node_list:
      self.connect(node)

  def connect(self, connect_node):
    """Add a node to the target list.

    """
    self.nc[connect_node] = nc = NodeController(self, connect_node)

  def getresult(self):
    """Return the results of the call.

    """
    return self.results

  def run(self):
    """Wrapper over reactor.run().

    This function simply calls reactor.run() if we have any requests
    queued, otherwise it does nothing.

    """
    for node, nc in self.nc.items():
      self.results[node] = nc.get_response()


def call_volume_list(node_list, vg_name):
  """Gets the logical volumes present in a given volume group.

  This is a multi-node call.

  """
  c = Client("volume_list", [vg_name])
  c.connect_list(node_list)
  c.run()
  return c.getresult()


def call_vg_list(node_list):
  """Gets the volume group list.

  This is a multi-node call.

  """
  c = Client("vg_list", [])
  c.connect_list(node_list)
  c.run()
  return c.getresult()


def call_bridges_exist(node, bridges_list):
  """Checks if a node has all the bridges given.

  This method checks if all bridges given in the bridges_list are
  present on the remote node, so that an instance that uses interfaces
  on those bridges can be started.

  This is a single-node call.

  """
  c = Client("bridges_exist", [bridges_list])
  c.connect(node)
  c.run()
  return c.getresult().get(node, False)


def call_instance_start(node, instance, extra_args):
  """Starts an instance.

  This is a single-node call.

  """
  c = Client("instance_start", [instance.ToDict(), extra_args])
  c.connect(node)
  c.run()
  return c.getresult().get(node, False)


def call_instance_shutdown(node, instance):
  """Stops an instance.

  This is a single-node call.

  """
  c = Client("instance_shutdown", [instance.ToDict()])
  c.connect(node)
  c.run()
  return c.getresult().get(node, False)


def call_instance_migrate(node, instance, target, live):
  """Migrate an instance.

  This is a single-node call.

  """
  c = Client("instance_migrate", [instance.name, target, live])
  c.connect(node)
  c.run()
  return c.getresult().get(node, False)


def call_instance_reboot(node, instance, reboot_type, extra_args):
  """Reboots an instance.

  This is a single-node call.

  """
  c = Client("instance_reboot", [instance.ToDict(), reboot_type, extra_args])
  c.connect(node)
  c.run()
  return c.getresult().get(node, False)


def call_instance_os_add(node, inst, osdev, swapdev):
  """Installs an OS on the given instance.

  This is a single-node call.

  """
  params = [inst.ToDict(), osdev, swapdev]
  c = Client("instance_os_add", params)
  c.connect(node)
  c.run()
  return c.getresult().get(node, False)


def call_instance_run_rename(node, inst, old_name, osdev, swapdev):
  """Run the OS rename script for an instance.

  This is a single-node call.

  """
  params = [inst.ToDict(), old_name, osdev, swapdev]
  c = Client("instance_run_rename", params)
  c.connect(node)
  c.run()
  return c.getresult().get(node, False)


def call_instance_info(node, instance):
  """Returns information about a single instance.

  This is a single-node call.

  """
  c = Client("instance_info", [instance])
  c.connect(node)
  c.run()
  return c.getresult().get(node, False)


def call_all_instances_info(node_list):
  """Returns information about all instances on a given node.

  This is a single-node call.

  """
  c = Client("all_instances_info", [])
  c.connect_list(node_list)
  c.run()
  return c.getresult()


def call_instance_list(node_list):
  """Returns the list of running instances on a given node.

  This is a single-node call.

  """
  c = Client("instance_list", [])
  c.connect_list(node_list)
  c.run()
  return c.getresult()


def call_node_tcp_ping(node, source, target, port, timeout, live_port_needed):
  """Do a TcpPing on the remote node

  This is a single-node call.
  """
  c = Client("node_tcp_ping", [source, target, port, timeout,
                               live_port_needed])
  c.connect(node)
  c.run()
  return c.getresult().get(node, False)


def call_node_info(node_list, vg_name):
  """Return node information.

  This will return memory information and volume group size and free
  space.

  This is a multi-node call.

  """
  c = Client("node_info", [vg_name])
  c.connect_list(node_list)
  c.run()
  retux = c.getresult()

  for node_name in retux:
    ret = retux.get(node_name, False)
    if type(ret) != dict:
      logger.Error("could not connect to node %s" % (node_name))
      ret = {}

    utils.CheckDict(ret,
                    { 'memory_total' : '-',
                      'memory_dom0' : '-',
                      'memory_free' : '-',
                      'vg_size' : 'node_unreachable',
                      'vg_free' : '-' },
                    "call_node_info",
                    )
  return retux


def call_node_add(node, dsa, dsapub, rsa, rsapub, ssh, sshpub):
  """Add a node to the cluster.

  This is a single-node call.

  """
  params = [dsa, dsapub, rsa, rsapub, ssh, sshpub]
  c = Client("node_add", params)
  c.connect(node)
  c.run()
  return c.getresult().get(node, False)


def call_node_verify(node_list, checkdict):
  """Request verification of given parameters.

  This is a multi-node call.

  """
  c = Client("node_verify", [checkdict])
  c.connect_list(node_list)
  c.run()
  return c.getresult()


def call_node_start_master(node, start_daemons):
  """Tells a node to activate itself as a master.

  This is a single-node call.

  """
  c = Client("node_start_master", [start_daemons])
  c.connect(node)
  c.run()
  return c.getresult().get(node, False)


def call_node_stop_master(node, stop_daemons):
  """Tells a node to demote itself from master status.

  This is a single-node call.

  """
  c = Client("node_stop_master", [stop_daemons])
  c.connect(node)
  c.run()
  return c.getresult().get(node, False)


def call_version(node_list):
  """Query node version.

  This is a multi-node call.

  """
  c = Client("version", [])
  c.connect_list(node_list)
  c.run()
  return c.getresult()


def call_blockdev_create(node, bdev, size, owner, on_primary, info):
  """Request creation of a given block device.

  This is a single-node call.

  """
  params = [bdev.ToDict(), size, owner, on_primary, info]
  c = Client("blockdev_create", params)
  c.connect(node)
  c.run()
  return c.getresult().get(node, False)


def call_blockdev_remove(node, bdev):
  """Request removal of a given block device.

  This is a single-node call.

  """
  c = Client("blockdev_remove", [bdev.ToDict()])
  c.connect(node)
  c.run()
  return c.getresult().get(node, False)


def call_blockdev_rename(node, devlist):
  """Request rename of the given block devices.

  This is a single-node call.

  """
  params = [(d.ToDict(), uid) for d, uid in devlist]
  c = Client("blockdev_rename", params)
  c.connect(node)
  c.run()
  return c.getresult().get(node, False)


def call_blockdev_assemble(node, disk, owner, on_primary):
  """Request assembling of a given block device.

  This is a single-node call.

  """
  params = [disk.ToDict(), owner, on_primary]
  c = Client("blockdev_assemble", params)
  c.connect(node)
  c.run()
  return c.getresult().get(node, False)


def call_blockdev_shutdown(node, disk):
  """Request shutdown of a given block device.

  This is a single-node call.

  """
  c = Client("blockdev_shutdown", [disk.ToDict()])
  c.connect(node)
  c.run()
  return c.getresult().get(node, False)


def call_blockdev_addchildren(node, bdev, ndevs):
  """Request adding a list of children to a (mirroring) device.

  This is a single-node call.

  """
  params = [bdev.ToDict(), [disk.ToDict() for disk in ndevs]]
  c = Client("blockdev_addchildren", params)
  c.connect(node)
  c.run()
  return c.getresult().get(node, False)


def call_blockdev_removechildren(node, bdev, ndevs):
  """Request removing a list of children from a (mirroring) device.

  This is a single-node call.

  """
  params = [bdev.ToDict(), [disk.ToDict() for disk in ndevs]]
  c = Client("blockdev_removechildren", params)
  c.connect(node)
  c.run()
  return c.getresult().get(node, False)


def call_blockdev_getmirrorstatus(node, disks):
  """Request status of a (mirroring) device.

  This is a single-node call.

  """
  params = [dsk.ToDict() for dsk in disks]
  c = Client("blockdev_getmirrorstatus", params)
  c.connect(node)
  c.run()
  return c.getresult().get(node, False)


def call_blockdev_find(node, disk):
  """Request identification of a given block device.

  This is a single-node call.

  """
  c = Client("blockdev_find", [disk.ToDict()])
  c.connect(node)
  c.run()
  return c.getresult().get(node, False)


def call_blockdev_close(node, disks):
  """Closes the given block devices.

  This is a single-node call.

  """
  params = [cf.ToDict() for cf in disks]
  c = Client("blockdev_close", params)
  c.connect(node)
  c.run()
  return c.getresult().get(node, False)


def call_upload_file(node_list, file_name):
  """Upload a file.

  The node will refuse the operation in case the file is not on the
  approved file list.

  This is a multi-node call.

  """
  fh = file(file_name)
  try:
    data = fh.read()
  finally:
    fh.close()
  st = os.stat(file_name)
  params = [file_name, data, st.st_mode, st.st_uid, st.st_gid,
            st.st_atime, st.st_mtime]
  c = Client("upload_file", params)
  c.connect_list(node_list)
  c.run()
  return c.getresult()


def call_os_diagnose(node_list):
  """Request a diagnose of OS definitions.

  This is a multi-node call.

  """
  c = Client("os_diagnose", [])
  c.connect_list(node_list)
  c.run()
  result = c.getresult()
  new_result = {}
  for node_name in result:
    if result[node_name]:
      nr = [objects.OS.FromDict(oss) for oss in result[node_name]]
    else:
      nr = []
    new_result[node_name] = nr
  return new_result


def call_os_get(node, name):
  """Returns an OS definition.

  This is a single-node call.

  """
  c = Client("os_get", [name])
  c.connect(node)
  c.run()
  result = c.getresult().get(node, False)
  if isinstance(result, dict):
    return objects.OS.FromDict(result)
  else:
    return result


def call_hooks_runner(node_list, hpath, phase, env):
  """Call the hooks runner.

  Args:
    - op: the OpCode instance
    - env: a dictionary with the environment

  This is a multi-node call.

  """
  params = [hpath, phase, env]
  c = Client("hooks_runner", params)
  c.connect_list(node_list)
  c.run()
  result = c.getresult()
  return result


def call_iallocator_runner(node, name, idata):
  """Call an iallocator on a remote node

  Args:
    - name: the iallocator name
    - input: the json-encoded input string

  This is a single-node call.

  """
  params = [name, idata]
  c = Client("iallocator_runner", params)
  c.connect(node)
  c.run()
  result = c.getresult().get(node, False)
  return result


def call_blockdev_grow(node, cf_bdev, amount):
  """Request a snapshot of the given block device.

  This is a single-node call.

  """
  c = Client("blockdev_grow", [cf_bdev.ToDict(), amount])
  c.connect(node)
  c.run()
  return c.getresult().get(node, False)


def call_blockdev_snapshot(node, cf_bdev):
  """Request a snapshot of the given block device.

  This is a single-node call.

  """
  c = Client("blockdev_snapshot", [cf_bdev.ToDict()])
  c.connect(node)
  c.run()
  return c.getresult().get(node, False)


def call_snapshot_export(node, snap_bdev, dest_node, instance):
  """Request the export of a given snapshot.

  This is a single-node call.

  """
  params = [snap_bdev.ToDict(), dest_node, instance.ToDict()]
  c = Client("snapshot_export", params)
  c.connect(node)
  c.run()
  return c.getresult().get(node, False)


def call_finalize_export(node, instance, snap_disks):
  """Request the completion of an export operation.

  This writes the export config file, etc.

  This is a single-node call.

  """
  flat_disks = []
  for disk in snap_disks:
    flat_disks.append(disk.ToDict())
  params = [instance.ToDict(), flat_disks]
  c = Client("finalize_export", params)
  c.connect(node)
  c.run()
  return c.getresult().get(node, False)


def call_export_info(node, path):
  """Queries the export information in a given path.

  This is a single-node call.

  """
  c = Client("export_info", [path])
  c.connect(node)
  c.run()
  result = c.getresult().get(node, False)
  if not result:
    return result
  return objects.SerializableConfigParser.Loads(str(result))


def call_instance_os_import(node, inst, osdev, swapdev, src_node, src_image):
  """Request the import of a backup into an instance.

  This is a single-node call.

  """
  params = [inst.ToDict(), osdev, swapdev, src_node, src_image]
  c = Client("instance_os_import", params)
  c.connect(node)
  c.run()
  return c.getresult().get(node, False)


def call_export_list(node_list):
  """Gets the stored exports list.

  This is a multi-node call.

  """
  c = Client("export_list", [])
  c.connect_list(node_list)
  c.run()
  result = c.getresult()
  return result


def call_export_remove(node, export):
  """Requests removal of a given export.

  This is a single-node call.

  """
  c = Client("export_remove", [export])
  c.connect(node)
  c.run()
  return c.getresult().get(node, False)


def call_node_leave_cluster(node):
  """Requests a node to clean the cluster information it has.

  This will remove the configuration information from the ganeti data
  dir.

  This is a single-node call.

  """
  c = Client("node_leave_cluster", [])
  c.connect(node)
  c.run()
  return c.getresult().get(node, False)


def call_node_volumes(node_list):
  """Gets all volumes on node(s).

  This is a multi-node call.

  """
  c = Client("node_volumes", [])
  c.connect_list(node_list)
  c.run()
  return c.getresult()


def call_test_delay(node_list, duration):
  """Sleep for a fixed time on given node(s).

  This is a multi-node call.

  """
  c = Client("test_delay", [duration])
  c.connect_list(node_list)
  c.run()
  return c.getresult()


def call_file_storage_dir_create(node, file_storage_dir):
  """Create the given file storage directory.

  This is a single-node call.

  """
  c = Client("file_storage_dir_create", [file_storage_dir])
  c.connect(node)
  c.run()
  return c.getresult().get(node, False)


def call_file_storage_dir_remove(node, file_storage_dir):
  """Remove the given file storage directory.

  This is a single-node call.

  """
  c = Client("file_storage_dir_remove", [file_storage_dir])
  c.connect(node)
  c.run()
  return c.getresult().get(node, False)


def call_file_storage_dir_rename(node, old_file_storage_dir,
                                 new_file_storage_dir):
  """Rename file storage directory.

  This is a single-node call.

  """
  c = Client("file_storage_dir_rename",
             [old_file_storage_dir, new_file_storage_dir])
  c.connect(node)
  c.run()
  return c.getresult().get(node, False)