Synnefo » snf-ganeti

#

#

# Copyright (C) 2006, 2007, 2008 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.

"""Remote API base resources library.

"""

import ganeti.cli

import ganeti.opcodes

from ganeti import luxi

from ganeti import rapi

from ganeti import http

def BuildUriList(ids, uri_format, uri_fields=("name", "uri")):

  """Builds a URI list as used by index resources.

  @param ids: list of ids as strings

  @param uri_format: format to be applied for URI

  @param uri_fields: optional parameter for field IDs

  """

  (field_id, field_uri) = uri_fields

  def _MapId(m_id):

    return { field_id: m_id, field_uri: uri_format % m_id, }

  # Make sure the result is sorted, makes it nicer to look at and simplifies

  # unittests.

  ids.sort()

  return map(_MapId, ids)

def ExtractField(sequence, index):

  """Creates a list containing one column out of a list of lists.

  @param sequence: sequence of lists

  @param index: index of field

  """

  return map(lambda item: item[index], sequence)

def MapFields(names, data):

  """Maps two lists into one dictionary.

  Example::

      >>> MapFields(["a", "b"], ["foo", 123])

      {'a': 'foo', 'b': 123}

  @param names: field names (list of strings)

  @param data: field data (list)

  """

  if len(names) != len(data):

    raise AttributeError("Names and data must have the same length")

  return dict(zip(names, data))

def _Tags_GET(kind, name=""):

  """Helper function to retrieve tags.

  """

  op = ganeti.opcodes.OpGetTags(kind=kind, name=name)

  tags = ganeti.cli.SubmitOpCode(op)

  return list(tags)

def _Tags_PUT(kind, tags, name=""):

  """Helper function to set tags.

  """

  cl = luxi.Client()

  return cl.SubmitJob([ganeti.opcodes.OpAddTags(kind=kind, name=name,

                                                tags=tags)])

def _Tags_DELETE(kind, tags, name=""):

  """Helper function to delete tags.

  """

  cl = luxi.Client()

  return cl.SubmitJob([ganeti.opcodes.OpDelTags(kind=kind, name=name,

                                                tags=tags)])

def MapBulkFields(itemslist, fields):

  """Map value to field name in to one dictionary.

  @param itemslist: a list of items values

  @param fields: a list of items names

  @return: a list of mapped dictionaries

  """

  items_details = []

  for item in itemslist:

    mapped = MapFields(fields, item)

    items_details.append(mapped)

  return items_details

def MakeParamsDict(opts, params):

  """Makes params dictionary out of a option set.

  This function returns a dictionary needed for hv or be parameters. But only

  those fields which provided in the option set. Takes parameters frozensets

  from constants.

  @type opts: dict

  @param opts: selected options

  @type params: frozenset

  @param params: subset of options

  @rtype: dict

  @return: dictionary of options, filtered by given subset.

  """

  result = {}

  for p in params:

    try:

      value = opts[p]

    except KeyError:

      continue

    result[p] = value

  return result

class R_Generic(object):

  """Generic class for resources.

  """

  # Default permission requirements

  GET_ACCESS = []

  PUT_ACCESS = [rapi.RAPI_ACCESS_WRITE]

  POST_ACCESS = [rapi.RAPI_ACCESS_WRITE]

  DELETE_ACCESS = [rapi.RAPI_ACCESS_WRITE]

  def __init__(self, items, queryargs, req):

    """Generic resource constructor.

    @param items: a list with variables encoded in the URL

    @param queryargs: a dictionary with additional options from URL

    """

    self.items = items

    self.queryargs = queryargs

    self.req = req

    self.sn = None

  def getSerialNumber(self):

    """Get Serial Number.

    """

    return self.sn

  def _checkIntVariable(self, name):

    """Return the parsed value of an int argument.

    """

    val = self.queryargs.get(name, 0)

    if isinstance(val, list):

      if val:

        val = val[0]

      else:

        val = 0

    try:

      val = int(val)

    except (ValueError, TypeError), err:

      raise http.HttpBadRequest("Invalid value for the"

                                " '%s' parameter" % (name,))

    return val

  def getBodyParameter(self, name, *args):

    """Check and return the value for a given parameter.

    If a second parameter is not given, an error will be returned,

    otherwise this parameter specifies the default value.

    @param name: the required parameter

    """

    if name in self.req.request_body:

      return self.req.request_body[name]

    elif args:

      return args[0]

    else:

      raise http.HttpBadRequest("Required parameter '%s' is missing" %

                                name)

  def useLocking(self):

    """Check if the request specifies locking.

    """

    return self._checkIntVariable('lock')

  def useBulk(self):

    """Check if the request specifies bulk querying.

    """

    return self._checkIntVariable('bulk')