Synnefo » snf-ganeti

#

#

# Copyright (C) 2006, 2007, 2011, 2012, 2013 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.

"""Module for the LUXI protocol

This module implements the local unix socket protocol. You only need

this module and the opcodes module in the client program in order to

communicate with the master.

The module is also used by the master daemon.

"""

import logging

from ganeti import serializer

from ganeti import constants

from ganeti import errors

from ganeti import objects

from ganeti import pathutils

from ganeti.rpc import transport as t

from ganeti.rpc.errors import (ProtocolError, ConnectionClosedError,

                               TimeoutError, RequestError, NoMasterError,

                               PermissionError)

__all__ = [

  # functions:

  "ProtocolError",

  "ConnectionClosedError",

  "TimeoutError",

  "RequestError",

  "NoMasterError",

  "PermissionError",

  "ParseRequest",

  "ParseResponse",

  "FormatRequest",

  "FormatResponse",

  "CallLuxiMethod",

  # classes:

  "Client"

  ]

KEY_METHOD = constants.LUXI_KEY_METHOD

KEY_ARGS = constants.LUXI_KEY_ARGS

KEY_SUCCESS = constants.LUXI_KEY_SUCCESS

KEY_RESULT = constants.LUXI_KEY_RESULT

KEY_VERSION = constants.LUXI_KEY_VERSION

REQ_SUBMIT_JOB = constants.LUXI_REQ_SUBMIT_JOB

REQ_SUBMIT_JOB_TO_DRAINED_QUEUE = constants.LUXI_REQ_SUBMIT_JOB_TO_DRAINED_QUEUE

REQ_SUBMIT_MANY_JOBS = constants.LUXI_REQ_SUBMIT_MANY_JOBS

REQ_PICKUP_JOB = constants.LUXI_REQ_PICKUP_JOB

REQ_WAIT_FOR_JOB_CHANGE = constants.LUXI_REQ_WAIT_FOR_JOB_CHANGE

REQ_CANCEL_JOB = constants.LUXI_REQ_CANCEL_JOB

REQ_ARCHIVE_JOB = constants.LUXI_REQ_ARCHIVE_JOB

REQ_CHANGE_JOB_PRIORITY = constants.LUXI_REQ_CHANGE_JOB_PRIORITY

REQ_AUTO_ARCHIVE_JOBS = constants.LUXI_REQ_AUTO_ARCHIVE_JOBS

REQ_QUERY = constants.LUXI_REQ_QUERY

REQ_QUERY_FIELDS = constants.LUXI_REQ_QUERY_FIELDS

REQ_QUERY_JOBS = constants.LUXI_REQ_QUERY_JOBS

REQ_QUERY_INSTANCES = constants.LUXI_REQ_QUERY_INSTANCES

REQ_QUERY_NODES = constants.LUXI_REQ_QUERY_NODES

REQ_QUERY_GROUPS = constants.LUXI_REQ_QUERY_GROUPS

REQ_QUERY_NETWORKS = constants.LUXI_REQ_QUERY_NETWORKS

REQ_QUERY_EXPORTS = constants.LUXI_REQ_QUERY_EXPORTS

REQ_QUERY_CONFIG_VALUES = constants.LUXI_REQ_QUERY_CONFIG_VALUES

REQ_QUERY_CLUSTER_INFO = constants.LUXI_REQ_QUERY_CLUSTER_INFO

REQ_QUERY_TAGS = constants.LUXI_REQ_QUERY_TAGS

REQ_SET_DRAIN_FLAG = constants.LUXI_REQ_SET_DRAIN_FLAG

REQ_SET_WATCHER_PAUSE = constants.LUXI_REQ_SET_WATCHER_PAUSE

REQ_ALL = constants.LUXI_REQ_ALL

DEF_RWTO = constants.LUXI_DEF_RWTO

WFJC_TIMEOUT = constants.LUXI_WFJC_TIMEOUT

def ParseRequest(msg):

  """Parses a LUXI request message.

  """

  try:

    request = serializer.LoadJson(msg)

  except ValueError, err:

    raise ProtocolError("Invalid LUXI request (parsing error): %s" % err)

  logging.debug("LUXI request: %s", request)

  if not isinstance(request, dict):

    logging.error("LUXI request not a dict: %r", msg)

    raise ProtocolError("Invalid LUXI request (not a dict)")

  method = request.get(KEY_METHOD, None) # pylint: disable=E1103

  args = request.get(KEY_ARGS, None) # pylint: disable=E1103

  version = request.get(KEY_VERSION, None) # pylint: disable=E1103

  if method is None or args is None:

    logging.error("LUXI request missing method or arguments: %r", msg)

    raise ProtocolError(("Invalid LUXI request (no method or arguments"

                         " in request): %r") % msg)

  return (method, args, version)

def ParseResponse(msg):

  """Parses a LUXI response message.

  """

  # Parse the result

  try:

    data = serializer.LoadJson(msg)

  except KeyboardInterrupt:

    raise

  except Exception, err:

    raise ProtocolError("Error while deserializing response: %s" % str(err))

  # Validate response

  if not (isinstance(data, dict) and

          KEY_SUCCESS in data and

          KEY_RESULT in data):

    raise ProtocolError("Invalid response from server: %r" % data)

  return (data[KEY_SUCCESS], data[KEY_RESULT],

          data.get(KEY_VERSION, None)) # pylint: disable=E1103

def FormatResponse(success, result, version=None):

  """Formats a LUXI response message.

  """

  response = {

    KEY_SUCCESS: success,

    KEY_RESULT: result,

    }

  if version is not None:

    response[KEY_VERSION] = version

  logging.debug("LUXI response: %s", response)

  return serializer.DumpJson(response)

def FormatRequest(method, args, version=None):

  """Formats a LUXI request message.

  """

  # Build request

  request = {

    KEY_METHOD: method,

    KEY_ARGS: args,

    }

  if version is not None:

    request[KEY_VERSION] = version

  # Serialize the request

  return serializer.DumpJson(request)

def CallLuxiMethod(transport_cb, method, args, version=None):

  """Send a LUXI request via a transport and return the response.

  """

  assert callable(transport_cb)

  request_msg = FormatRequest(method, args, version=version)

  # Send request and wait for response

  response_msg = transport_cb(request_msg)

  (success, result, resp_version) = ParseResponse(response_msg)

  # Verify version if there was one in the response

  if resp_version is not None and resp_version != version:

    raise errors.LuxiError("LUXI version mismatch, client %s, response %s" %

                           (version, resp_version))

  if success:

    return result

  errors.MaybeRaise(result)

  raise RequestError(result)

class Client(object):

  """High-level client implementation.

  This uses a backing Transport-like class on top of which it

  implements data serialization/deserialization.

  """

  def __init__(self, address=None, timeouts=None, transport=t.Transport):

    """Constructor for the Client class.

    Arguments:

      - address: a valid address the the used transport class

      - timeout: a list of timeouts, to be used on connect and read/write

      - transport: a Transport-like class

    If timeout is not passed, the default timeouts of the transport

    class are used.

    """

    if address is None:

      address = pathutils.MASTER_SOCKET

    self.address = address

    self.timeouts = timeouts

    self.transport_class = transport

    self.transport = None

    self._InitTransport()

  def _InitTransport(self):

    """(Re)initialize the transport if needed.

    """

    if self.transport is None:

      self.transport = self.transport_class(self.address,

                                            timeouts=self.timeouts)

  def _CloseTransport(self):

    """Close the transport, ignoring errors.

    """

    if self.transport is None:

      return

    try:

      old_transp = self.transport

      self.transport = None

      old_transp.Close()

    except Exception: # pylint: disable=W0703

      pass

  def _SendMethodCall(self, data):

    # Send request and wait for response

    try:

      self._InitTransport()

      return self.transport.Call(data)

    except Exception:

      self._CloseTransport()

      raise

  def Close(self):

    """Close the underlying connection.

    """

    self._CloseTransport()

  def CallMethod(self, method, args):

    """Send a generic request and return the response.

    """

    if not isinstance(args, (list, tuple)):

      raise errors.ProgrammerError("Invalid parameter passed to CallMethod:"

                                   " expected list, got %s" % type(args))

    return CallLuxiMethod(self._SendMethodCall, method, args,

                          version=constants.LUXI_VERSION)

  def SetQueueDrainFlag(self, drain_flag):

    return self.CallMethod(REQ_SET_DRAIN_FLAG, (drain_flag, ))

  def SetWatcherPause(self, until):

    return self.CallMethod(REQ_SET_WATCHER_PAUSE, (until, ))

  def PickupJob(self, job):

    return self.CallMethod(REQ_PICKUP_JOB, (job,))

  def SubmitJob(self, ops):

    ops_state = map(lambda op: op.__getstate__(), ops)

    return self.CallMethod(REQ_SUBMIT_JOB, (ops_state, ))

  def SubmitJobToDrainedQueue(self, ops):

    ops_state = map(lambda op: op.__getstate__(), ops)

    return self.CallMethod(REQ_SUBMIT_JOB_TO_DRAINED_QUEUE, (ops_state, ))

  def SubmitManyJobs(self, jobs):

    jobs_state = []

    for ops in jobs:

      jobs_state.append([op.__getstate__() for op in ops])

    return self.CallMethod(REQ_SUBMIT_MANY_JOBS, (jobs_state, ))

  def CancelJob(self, job_id):

    return self.CallMethod(REQ_CANCEL_JOB, (job_id, ))

  def ArchiveJob(self, job_id):

    return self.CallMethod(REQ_ARCHIVE_JOB, (job_id, ))

  def ChangeJobPriority(self, job_id, priority):

    return self.CallMethod(REQ_CHANGE_JOB_PRIORITY, (job_id, priority))

  def AutoArchiveJobs(self, age):

    timeout = (DEF_RWTO - 1) / 2

    return self.CallMethod(REQ_AUTO_ARCHIVE_JOBS, (age, timeout))

  def WaitForJobChangeOnce(self, job_id, fields,

                           prev_job_info, prev_log_serial,

                           timeout=WFJC_TIMEOUT):

    """Waits for changes on a job.

    @param job_id: Job ID

    @type fields: list

    @param fields: List of field names to be observed

    @type prev_job_info: None or list

    @param prev_job_info: Previously received job information

    @type prev_log_serial: None or int/long

    @param prev_log_serial: Highest log serial number previously received

    @type timeout: int/float

    @param timeout: Timeout in seconds (values larger than L{WFJC_TIMEOUT} will

                    be capped to that value)

    """

    assert timeout >= 0, "Timeout can not be negative"

    return self.CallMethod(REQ_WAIT_FOR_JOB_CHANGE,

                           (job_id, fields, prev_job_info,

                            prev_log_serial,

                            min(WFJC_TIMEOUT, timeout)))

  def WaitForJobChange(self, job_id, fields, prev_job_info, prev_log_serial):

    while True:

      result = self.WaitForJobChangeOnce(job_id, fields,

                                         prev_job_info, prev_log_serial)

      if result != constants.JOB_NOTCHANGED:

        break

    return result

  def Query(self, what, fields, qfilter):

    """Query for resources/items.

    @param what: One of L{constants.QR_VIA_LUXI}

    @type fields: List of strings

    @param fields: List of requested fields

    @type qfilter: None or list

    @param qfilter: Query filter

    @rtype: L{objects.QueryResponse}

    """

    result = self.CallMethod(REQ_QUERY, (what, fields, qfilter))

    return objects.QueryResponse.FromDict(result)

  def QueryFields(self, what, fields):

    """Query for available fields.

    @param what: One of L{constants.QR_VIA_LUXI}

    @type fields: None or list of strings

    @param fields: List of requested fields

    @rtype: L{objects.QueryFieldsResponse}

    """

    result = self.CallMethod(REQ_QUERY_FIELDS, (what, fields))

    return objects.QueryFieldsResponse.FromDict(result)

  def QueryJobs(self, job_ids, fields):

    return self.CallMethod(REQ_QUERY_JOBS, (job_ids, fields))

  def QueryInstances(self, names, fields, use_locking):

    return self.CallMethod(REQ_QUERY_INSTANCES, (names, fields, use_locking))

  def QueryNodes(self, names, fields, use_locking):

    return self.CallMethod(REQ_QUERY_NODES, (names, fields, use_locking))

  def QueryGroups(self, names, fields, use_locking):

    return self.CallMethod(REQ_QUERY_GROUPS, (names, fields, use_locking))

  def QueryNetworks(self, names, fields, use_locking):

    return self.CallMethod(REQ_QUERY_NETWORKS, (names, fields, use_locking))

  def QueryExports(self, nodes, use_locking):

    return self.CallMethod(REQ_QUERY_EXPORTS, (nodes, use_locking))

  def QueryClusterInfo(self):

    return self.CallMethod(REQ_QUERY_CLUSTER_INFO, ())

  def QueryConfigValues(self, fields):

    return self.CallMethod(REQ_QUERY_CONFIG_VALUES, (fields, ))

  def QueryTags(self, kind, name):

    return self.CallMethod(REQ_QUERY_TAGS, (kind, name))