qa_utils.py

#
#

# Copyright (C) 2007, 2011 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.


"""Utilities for QA tests.

"""

import os
import re
import sys
import subprocess
import random
import tempfile

from ganeti import utils
from ganeti import compat
from ganeti import constants

import qa_config
import qa_error


_INFO_SEQ = None
_WARNING_SEQ = None
_ERROR_SEQ = None
_RESET_SEQ = None

_MULTIPLEXERS = {}


def _SetupColours():
  """Initializes the colour constants.

  """
  # pylint: disable-msg=W0603
  # due to global usage
  global _INFO_SEQ, _WARNING_SEQ, _ERROR_SEQ, _RESET_SEQ

  # Don't use colours if stdout isn't a terminal
  if not sys.stdout.isatty():
    return

  try:
    import curses
  except ImportError:
    # Don't use colours if curses module can't be imported
    return

  curses.setupterm()

  _RESET_SEQ = curses.tigetstr("op")

  setaf = curses.tigetstr("setaf")
  _INFO_SEQ = curses.tparm(setaf, curses.COLOR_GREEN)
  _WARNING_SEQ = curses.tparm(setaf, curses.COLOR_YELLOW)
  _ERROR_SEQ = curses.tparm(setaf, curses.COLOR_RED)


_SetupColours()


def AssertIn(item, sequence):
  """Raises an error when item is not in sequence.

  """
  if item not in sequence:
    raise qa_error.Error('%r not in %r' % (item, sequence))


def AssertEqual(first, second):
  """Raises an error when values aren't equal.

  """
  if not first == second:
    raise qa_error.Error('%r == %r' % (first, second))


def AssertNotEqual(first, second):
  """Raises an error when values are equal.

  """
  if not first != second:
    raise qa_error.Error('%r != %r' % (first, second))


def AssertMatch(string, pattern):
  """Raises an error when string doesn't match regexp pattern.

  """
  if not re.match(pattern, string):
    raise qa_error.Error("%r doesn't match /%r/" % (string, pattern))


def AssertCommand(cmd, fail=False, node=None):
  """Checks that a remote command succeeds.

  @param cmd: either a string (the command to execute) or a list (to
      be converted using L{utils.ShellQuoteArgs} into a string)
  @type fail: boolean
  @param fail: if the command is expected to fail instead of succeeding
  @param node: if passed, it should be the node on which the command
      should be executed, instead of the master node (can be either a
      dict or a string)

  """
  if node is None:
    node = qa_config.GetMasterNode()

  if isinstance(node, basestring):
    nodename = node
  else:
    nodename = node["primary"]

  if isinstance(cmd, basestring):
    cmdstr = cmd
  else:
    cmdstr = utils.ShellQuoteArgs(cmd)

  rcode = StartSSH(nodename, cmdstr).wait()

  if fail:
    if rcode == 0:
      raise qa_error.Error("Command '%s' on node %s was expected to fail but"
                           " didn't" % (cmdstr, nodename))
  else:
    if rcode != 0:
      raise qa_error.Error("Command '%s' on node %s failed, exit code %s" %
                           (cmdstr, nodename, rcode))

  return rcode


def GetSSHCommand(node, cmd, strict=True, opts=None):
  """Builds SSH command to be executed.

  @type node: string
  @param node: node the command should run on
  @type cmd: string
  @param cmd: command to be executed in the node; if None or empty
      string, no command will be executed
  @type strict: boolean
  @param strict: whether to enable strict host key checking
  @type opts: list
  @param opts: list of additional options

  """
  args = [ 'ssh', '-oEscapeChar=none', '-oBatchMode=yes', '-l', 'root', '-t' ]

  if strict:
    tmp = 'yes'
  else:
    tmp = 'no'
  args.append('-oStrictHostKeyChecking=%s' % tmp)
  args.append('-oClearAllForwardings=yes')
  args.append('-oForwardAgent=yes')
  if opts:
    args.extend(opts)
  if node in _MULTIPLEXERS:
    spath = _MULTIPLEXERS[node][0]
    args.append('-oControlPath=%s' % spath)
    args.append('-oControlMaster=no')
  args.append(node)
  if cmd:
    args.append(cmd)

  return args


def StartLocalCommand(cmd, **kwargs):
  """Starts a local command.

  """
  print "Command: %s" % utils.ShellQuoteArgs(cmd)
  return subprocess.Popen(cmd, shell=False, **kwargs)


def StartSSH(node, cmd, strict=True):
  """Starts SSH.

  """
  return StartLocalCommand(GetSSHCommand(node, cmd, strict=strict))


def StartMultiplexer(node):
  """Starts a multiplexer command.

  @param node: the node for which to open the multiplexer

  """
  if node in _MULTIPLEXERS:
    return

  # Note: yes, we only need mktemp, since we'll remove the file anyway
  sname = tempfile.mktemp(prefix="ganeti-qa-multiplexer.")
  utils.RemoveFile(sname)
  opts = ["-N", "-oControlPath=%s" % sname, "-oControlMaster=yes"]
  print "Created socket at %s" % sname
  child = StartLocalCommand(GetSSHCommand(node, None, opts=opts))
  _MULTIPLEXERS[node] = (sname, child)


def CloseMultiplexers():
  """Closes all current multiplexers and cleans up.

  """
  for node in _MULTIPLEXERS.keys():
    (sname, child) = _MULTIPLEXERS.pop(node)
    utils.KillProcess(child.pid, timeout=10, waitpid=True)
    utils.RemoveFile(sname)


def GetCommandOutput(node, cmd):
  """Returns the output of a command executed on the given node.

  """
  p = StartLocalCommand(GetSSHCommand(node, cmd), stdout=subprocess.PIPE)
  AssertEqual(p.wait(), 0)
  return p.stdout.read()


def UploadFile(node, src):
  """Uploads a file to a node and returns the filename.

  Caller needs to remove the returned file on the node when it's not needed
  anymore.

  """
  # Make sure nobody else has access to it while preserving local permissions
  mode = os.stat(src).st_mode & 0700

  cmd = ('tmp=$(tempfile --mode %o --prefix gnt) && '
         '[[ -f "${tmp}" ]] && '
         'cat > "${tmp}" && '
         'echo "${tmp}"') % mode

  f = open(src, 'r')
  try:
    p = subprocess.Popen(GetSSHCommand(node, cmd), shell=False, stdin=f,
                         stdout=subprocess.PIPE)
    AssertEqual(p.wait(), 0)

    # Return temporary filename
    return p.stdout.read().strip()
  finally:
    f.close()


def UploadData(node, data, mode=0600, filename=None):
  """Uploads data to a node and returns the filename.

  Caller needs to remove the returned file on the node when it's not needed
  anymore.

  """
  if filename:
    tmp = "tmp=%s" % utils.ShellQuote(filename)
  else:
    tmp = "tmp=$(tempfile --mode %o --prefix gnt)" % mode
  cmd = ("%s && "
         "[[ -f \"${tmp}\" ]] && "
         "cat > \"${tmp}\" && "
         "echo \"${tmp}\"") % tmp

  p = subprocess.Popen(GetSSHCommand(node, cmd), shell=False,
                       stdin=subprocess.PIPE, stdout=subprocess.PIPE)
  p.stdin.write(data)
  p.stdin.close()
  AssertEqual(p.wait(), 0)

  # Return temporary filename
  return p.stdout.read().strip()


def BackupFile(node, path):
  """Creates a backup of a file on the node and returns the filename.

  Caller needs to remove the returned file on the node when it's not needed
  anymore.

  """
  cmd = ("tmp=$(tempfile --prefix .gnt --directory=$(dirname %s)) && "
         "[[ -f \"$tmp\" ]] && "
         "cp %s $tmp && "
         "echo $tmp") % (utils.ShellQuote(path), utils.ShellQuote(path))

  # Return temporary filename
  return GetCommandOutput(node, cmd).strip()


def _ResolveName(cmd, key):
  """Helper function.

  """
  master = qa_config.GetMasterNode()

  output = GetCommandOutput(master['primary'], utils.ShellQuoteArgs(cmd))
  for line in output.splitlines():
    (lkey, lvalue) = line.split(':', 1)
    if lkey == key:
      return lvalue.lstrip()
  raise KeyError("Key not found")


def ResolveInstanceName(instance):
  """Gets the full name of an instance.

  @type instance: string
  @param instance: Instance name

  """
  return _ResolveName(['gnt-instance', 'info', instance],
                      'Instance name')


def ResolveNodeName(node):
  """Gets the full name of a node.

  """
  return _ResolveName(['gnt-node', 'info', node['primary']],
                      'Node name')


def GetNodeInstances(node, secondaries=False):
  """Gets a list of instances on a node.

  """
  master = qa_config.GetMasterNode()
  node_name = ResolveNodeName(node)

  # Get list of all instances
  cmd = ['gnt-instance', 'list', '--separator=:', '--no-headers',
         '--output=name,pnode,snodes']
  output = GetCommandOutput(master['primary'], utils.ShellQuoteArgs(cmd))

  instances = []
  for line in output.splitlines():
    (name, pnode, snodes) = line.split(':', 2)
    if ((not secondaries and pnode == node_name) or
        (secondaries and node_name in snodes.split(','))):
      instances.append(name)

  return instances


def _SelectQueryFields(rnd, fields):
  """Generates a list of fields for query tests.

  """
  # Create copy for shuffling
  fields = list(fields)
  rnd.shuffle(fields)

  # Check all fields
  yield fields
  yield sorted(fields)

  # Duplicate fields
  yield fields + fields

  # Check small groups of fields
  while fields:
    yield [fields.pop() for _ in range(rnd.randint(2, 10)) if fields]


def _List(listcmd, fields, names):
  """Runs a list command.

  """
  master = qa_config.GetMasterNode()

  cmd = [listcmd, "list", "--separator=|", "--no-header",
         "--output", ",".join(fields)]

  if names:
    cmd.extend(names)

  return GetCommandOutput(master["primary"],
                          utils.ShellQuoteArgs(cmd)).splitlines()


def GenericQueryTest(cmd, fields):
  """Runs a number of tests on query commands.

  @param cmd: Command name
  @param fields: List of field names

  """
  rnd = random.Random(hash(cmd))

  fields = list(fields)
  rnd.shuffle(fields)

  # Test a number of field combinations
  for testfields in _SelectQueryFields(rnd, fields):
    AssertCommand([cmd, "list", "--output", ",".join(testfields)])

  namelist_fn = compat.partial(_List, cmd, ["name"])

  # When no names were requested, the list must be sorted
  names = namelist_fn(None)
  AssertEqual(names, utils.NiceSort(names))

  # When requesting specific names, the order must be kept
  revnames = list(reversed(names))
  AssertEqual(namelist_fn(revnames), revnames)

  randnames = list(names)
  rnd.shuffle(randnames)
  AssertEqual(namelist_fn(randnames), randnames)

  # Listing unknown items must fail
  AssertCommand([cmd, "list", "this.name.certainly.does.not.exist"], fail=True)

  # Check exit code for listing unknown field
  AssertEqual(AssertCommand([cmd, "list", "--output=field/does/not/exist"],
                            fail=True),
              constants.EXIT_UNKNOWN_FIELD)


def GenericQueryFieldsTest(cmd, fields):
  master = qa_config.GetMasterNode()

  # Listing fields
  AssertCommand([cmd, "list-fields"])
  AssertCommand([cmd, "list-fields"] + fields)

  # Check listed fields (all, must be sorted)
  realcmd = [cmd, "list-fields", "--separator=|", "--no-headers"]
  output = GetCommandOutput(master["primary"],
                            utils.ShellQuoteArgs(realcmd)).splitlines()
  AssertEqual([line.split("|", 1)[0] for line in output],
              utils.NiceSort(fields))

  # Check exit code for listing unknown field
  AssertEqual(AssertCommand([cmd, "list-fields", "field/does/not/exist"],
                            fail=True),
              constants.EXIT_UNKNOWN_FIELD)


def _FormatWithColor(text, seq):
  if not seq:
    return text
  return "%s%s%s" % (seq, text, _RESET_SEQ)


FormatWarning = lambda text: _FormatWithColor(text, _WARNING_SEQ)
FormatError = lambda text: _FormatWithColor(text, _ERROR_SEQ)
FormatInfo = lambda text: _FormatWithColor(text, _INFO_SEQ)