Synnefo » snf-ganeti

{-| Unittests for ganeti-htools

-}

{-

Copyright (C) 2009, 2010 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 Ganeti.HTools.QC

    ( testUtils

    , testPeerMap

    , testContainer

    , testInstance

    , testNode

    , testText

    , testOpCodes

    , testJobs

    , testCluster

    , testLoader

    ) where

import Test.QuickCheck

import Test.QuickCheck.Batch

import Data.List (findIndex, intercalate)

import Data.Maybe

import Control.Monad

import qualified Text.JSON as J

import qualified Data.Map

import qualified Data.IntMap as IntMap

import qualified Ganeti.OpCodes as OpCodes

import qualified Ganeti.Jobs as Jobs

import qualified Ganeti.Luxi

import qualified Ganeti.HTools.CLI as CLI

import qualified Ganeti.HTools.Cluster as Cluster

import qualified Ganeti.HTools.Container as Container

import qualified Ganeti.HTools.ExtLoader

import qualified Ganeti.HTools.IAlloc as IAlloc

import qualified Ganeti.HTools.Instance as Instance

import qualified Ganeti.HTools.Loader as Loader

import qualified Ganeti.HTools.Luxi

import qualified Ganeti.HTools.Node as Node

import qualified Ganeti.HTools.PeerMap as PeerMap

import qualified Ganeti.HTools.Rapi

import qualified Ganeti.HTools.Simu

import qualified Ganeti.HTools.Text as Text

import qualified Ganeti.HTools.Types as Types

import qualified Ganeti.HTools.Utils as Utils

import qualified Ganeti.HTools.Version

-- * Constants

-- | Maximum memory (1TiB, somewhat random value)

maxMem :: Int

maxMem = 1024 * 1024

-- | Maximum disk (8TiB, somewhat random value)

maxDsk :: Int

maxDsk = 1024 * 1024 * 8

-- | Max CPUs (1024, somewhat random value)

maxCpu :: Int

maxCpu = 1024

-- * Helper functions

-- | Simple checker for whether OpResult is fail or pass

isFailure :: Types.OpResult a -> Bool

isFailure (Types.OpFail _) = True

isFailure _ = False

-- | Simple checker for whether Result is fail or pass

isOk :: Types.Result a -> Bool

isOk (Types.Ok _ ) = True

isOk _ = False

isBad :: Types.Result a  -> Bool

isBad = not . isOk

-- | Update an instance to be smaller than a node

setInstanceSmallerThanNode node inst =

    inst { Instance.mem = Node.availMem node `div` 2

         , Instance.dsk = Node.availDisk node `div` 2

         , Instance.vcpus = Node.availCpu node `div` 2

         }

-- | Create an instance given its spec

createInstance mem dsk vcpus =

    Instance.create "inst-unnamed" mem dsk vcpus "running" [] (-1) (-1)

-- | Create a small cluster by repeating a node spec

makeSmallCluster :: Node.Node -> Int -> Node.List

makeSmallCluster node count =

    let fn = Node.buildPeers node Container.empty

        namelst = map (\n -> (Node.name n, n)) (replicate count fn)

        (_, nlst) = Loader.assignIndices namelst

    in Container.fromAssocList nlst

-- | Checks if a node is "big" enough

isNodeBig :: Node.Node -> Int -> Bool

isNodeBig node size = Node.availDisk node > size * Types.unitDsk

                      && Node.availMem node > size * Types.unitMem

                      && Node.availCpu node > size * Types.unitCpu

canBalance :: Cluster.Table -> Bool -> Bool -> Bool

canBalance tbl dm evac = isJust $ Cluster.tryBalance tbl dm evac 0 0

-- * Arbitrary instances

-- copied from the introduction to quickcheck

instance Arbitrary Char where

    arbitrary = choose ('\32', '\128')

newtype DNSChar = DNSChar { dnsGetChar::Char }

instance Arbitrary DNSChar where

    arbitrary = do

      x <- elements (['a'..'z'] ++ ['0'..'9'] ++ "_-")

      return (DNSChar x)

getName :: Gen String

getName = do

  n <- choose (1, 64)

  dn <- vector n::Gen [DNSChar]

  return (map dnsGetChar dn)

getFQDN :: Gen String

getFQDN = do

  felem <- getName

  ncomps <- choose (1, 4)

  frest <- vector ncomps::Gen [[DNSChar]]

  let frest' = map (map dnsGetChar) frest

  return (felem ++ "." ++ intercalate "." frest')

-- let's generate a random instance

instance Arbitrary Instance.Instance where

    arbitrary = do

      name <- getFQDN

      mem <- choose (0, maxMem)

      dsk <- choose (0, maxDsk)

      run_st <- elements ["ERROR_up", "ERROR_down", "ADMIN_down"

                         , "ERROR_nodedown", "ERROR_nodeoffline"

                         , "running"

                         , "no_such_status1", "no_such_status2"]

      pn <- arbitrary

      sn <- arbitrary

      vcpus <- choose (0, maxCpu)

      return $ Instance.create name mem dsk vcpus run_st [] pn sn

-- and a random node

instance Arbitrary Node.Node where

    arbitrary = do

      name <- getFQDN

      mem_t <- choose (0, maxMem)

      mem_f <- choose (0, mem_t)

      mem_n <- choose (0, mem_t - mem_f)

      dsk_t <- choose (0, maxDsk)

      dsk_f <- choose (0, dsk_t)

      cpu_t <- choose (0, maxCpu)

      offl <- arbitrary

      let n = Node.create name (fromIntegral mem_t) mem_n mem_f

              (fromIntegral dsk_t) dsk_f (fromIntegral cpu_t) offl

          n' = Node.buildPeers n Container.empty

      return n'

-- replace disks

instance Arbitrary OpCodes.ReplaceDisksMode where

  arbitrary = elements [ OpCodes.ReplaceOnPrimary

                       , OpCodes.ReplaceOnSecondary

                       , OpCodes.ReplaceNewSecondary

                       , OpCodes.ReplaceAuto

                       ]

instance Arbitrary OpCodes.OpCode where

  arbitrary = do

    op_id <- elements [ "OP_TEST_DELAY"

                      , "OP_INSTANCE_REPLACE_DISKS"

                      , "OP_INSTANCE_FAILOVER"

                      , "OP_INSTANCE_MIGRATE"

                      ]

    (case op_id of

        "OP_TEST_DELAY" ->

          liftM3 OpCodes.OpTestDelay arbitrary arbitrary arbitrary

        "OP_INSTANCE_REPLACE_DISKS" ->

          liftM5 OpCodes.OpReplaceDisks arbitrary arbitrary

          arbitrary arbitrary arbitrary

        "OP_INSTANCE_FAILOVER" ->

          liftM2 OpCodes.OpFailoverInstance arbitrary arbitrary

        "OP_INSTANCE_MIGRATE" ->

          liftM3 OpCodes.OpMigrateInstance arbitrary arbitrary arbitrary

        _ -> fail "Wrong opcode")

instance Arbitrary Jobs.OpStatus where

  arbitrary = elements [minBound..maxBound]

instance Arbitrary Jobs.JobStatus where

  arbitrary = elements [minBound..maxBound]

-- * Actual tests

-- If the list is not just an empty element, and if the elements do

-- not contain commas, then join+split should be idepotent

prop_Utils_commaJoinSplit lst = lst /= [""] &&

                                all (not . elem ',') lst ==>

                                Utils.sepSplit ',' (Utils.commaJoin lst) == lst

-- Split and join should always be idempotent

prop_Utils_commaSplitJoin s = Utils.commaJoin (Utils.sepSplit ',' s) == s

testUtils =

  [ run prop_Utils_commaJoinSplit

  , run prop_Utils_commaSplitJoin

  ]

-- | Make sure add is idempotent

prop_PeerMap_addIdempotent pmap key em =

    fn puniq == fn (fn puniq)

    where _types = (pmap::PeerMap.PeerMap,

                    key::PeerMap.Key, em::PeerMap.Elem)

          fn = PeerMap.add key em

          puniq = PeerMap.accumArray const pmap

-- | Make sure remove is idempotent

prop_PeerMap_removeIdempotent pmap key =

    fn puniq == fn (fn puniq)

    where _types = (pmap::PeerMap.PeerMap, key::PeerMap.Key)

          fn = PeerMap.remove key

          puniq = PeerMap.accumArray const pmap

-- | Make sure a missing item returns 0

prop_PeerMap_findMissing pmap key =

    PeerMap.find key (PeerMap.remove key puniq) == 0

    where _types = (pmap::PeerMap.PeerMap, key::PeerMap.Key)

          puniq = PeerMap.accumArray const pmap

-- | Make sure an added item is found

prop_PeerMap_addFind pmap key em =

    PeerMap.find key (PeerMap.add key em puniq) == em

    where _types = (pmap::PeerMap.PeerMap,

                    key::PeerMap.Key, em::PeerMap.Elem)

          puniq = PeerMap.accumArray const pmap

-- | Manual check that maxElem returns the maximum indeed, or 0 for null

prop_PeerMap_maxElem pmap =

    PeerMap.maxElem puniq == if null puniq then 0

                             else (maximum . snd . unzip) puniq

    where _types = pmap::PeerMap.PeerMap

          puniq = PeerMap.accumArray const pmap

testPeerMap =

    [ run prop_PeerMap_addIdempotent

    , run prop_PeerMap_removeIdempotent

    , run prop_PeerMap_maxElem

    , run prop_PeerMap_addFind

    , run prop_PeerMap_findMissing

    ]

-- Container tests

prop_Container_addTwo cdata i1 i2 =

    fn i1 i2 cont == fn i2 i1 cont &&

       fn i1 i2 cont == fn i1 i2 (fn i1 i2 cont)

    where _types = (cdata::[Int],

                    i1::Int, i2::Int)

          cont = foldl (\c x -> Container.add x x c) Container.empty cdata

          fn x1 x2 = Container.addTwo x1 x1 x2 x2

testContainer =

    [ run prop_Container_addTwo ]

-- Simple instance tests, we only have setter/getters

prop_Instance_creat inst =

    Instance.name inst == Instance.alias inst

prop_Instance_setIdx inst idx =

    Instance.idx (Instance.setIdx inst idx) == idx

    where _types = (inst::Instance.Instance, idx::Types.Idx)

prop_Instance_setName inst name =

    Instance.name newinst == name &&

    Instance.alias newinst == name

    where _types = (inst::Instance.Instance, name::String)

          newinst = Instance.setName inst name

prop_Instance_setAlias inst name =

    Instance.name newinst == Instance.name inst &&

    Instance.alias newinst == name

    where _types = (inst::Instance.Instance, name::String)

          newinst = Instance.setAlias inst name

prop_Instance_setPri inst pdx =

    Instance.pNode (Instance.setPri inst pdx) == pdx

    where _types = (inst::Instance.Instance, pdx::Types.Ndx)

prop_Instance_setSec inst sdx =

    Instance.sNode (Instance.setSec inst sdx) == sdx

    where _types = (inst::Instance.Instance, sdx::Types.Ndx)

prop_Instance_setBoth inst pdx sdx =

    Instance.pNode si == pdx && Instance.sNode si == sdx

    where _types = (inst::Instance.Instance, pdx::Types.Ndx, sdx::Types.Ndx)

          si = Instance.setBoth inst pdx sdx

prop_Instance_runStatus_True inst =

    let run_st = Instance.running inst

        run_tx = Instance.runSt inst

    in

      run_tx `elem` Instance.runningStates ==> run_st

prop_Instance_runStatus_False inst =

    let run_st = Instance.running inst

        run_tx = Instance.runSt inst

    in

      run_tx `notElem` Instance.runningStates ==> not run_st

prop_Instance_shrinkMG inst =

    Instance.mem inst >= 2 * Types.unitMem ==>

        case Instance.shrinkByType inst Types.FailMem of

          Types.Ok inst' ->

              Instance.mem inst' == Instance.mem inst - Types.unitMem

          _ -> False

prop_Instance_shrinkMF inst =

    Instance.mem inst < 2 * Types.unitMem ==>

        isBad $ Instance.shrinkByType inst Types.FailMem

prop_Instance_shrinkCG inst =

    Instance.vcpus inst >= 2 * Types.unitCpu ==>

        case Instance.shrinkByType inst Types.FailCPU of

          Types.Ok inst' ->

              Instance.vcpus inst' == Instance.vcpus inst - Types.unitCpu

          _ -> False

prop_Instance_shrinkCF inst =

    Instance.vcpus inst < 2 * Types.unitCpu ==>

        isBad $ Instance.shrinkByType inst Types.FailCPU

prop_Instance_shrinkDG inst =

    Instance.dsk inst >= 2 * Types.unitDsk ==>

        case Instance.shrinkByType inst Types.FailDisk of

          Types.Ok inst' ->

              Instance.dsk inst' == Instance.dsk inst - Types.unitDsk

          _ -> False

prop_Instance_shrinkDF inst =

    Instance.dsk inst < 2 * Types.unitDsk ==>

        isBad $ Instance.shrinkByType inst Types.FailDisk

prop_Instance_setMovable inst m =

    Instance.movable inst' == m

    where inst' = Instance.setMovable inst m

testInstance =

    [ run prop_Instance_creat

    , run prop_Instance_setIdx

    , run prop_Instance_setName

    , run prop_Instance_setAlias

    , run prop_Instance_setPri

    , run prop_Instance_setSec

    , run prop_Instance_setBoth

    , run prop_Instance_runStatus_True

    , run prop_Instance_runStatus_False

    , run prop_Instance_shrinkMG

    , run prop_Instance_shrinkMF

    , run prop_Instance_shrinkCG

    , run prop_Instance_shrinkCF

    , run prop_Instance_shrinkDG

    , run prop_Instance_shrinkDF

    , run prop_Instance_setMovable

    ]

-- Instance text loader tests

prop_Text_Load_Instance name mem dsk vcpus status pnode snode pdx sdx =

    not (null pnode) && pdx >= 0 && sdx >= 0 ==>

    let vcpus_s = show vcpus

        dsk_s = show dsk

        mem_s = show mem

        rsdx = if pdx == sdx

               then sdx + 1

               else sdx

        ndx = if null snode

              then [(pnode, pdx)]

              else [(pnode, pdx), (snode, rsdx)]

        tags = ""

        inst = Text.loadInst ndx

               [name, mem_s, dsk_s, vcpus_s, status, pnode, snode, tags]::

               Maybe (String, Instance.Instance)

        fail1 = Text.loadInst ndx

               [name, mem_s, dsk_s, vcpus_s, status, pnode, pnode, tags]::

               Maybe (String, Instance.Instance)

        _types = ( name::String, mem::Int, dsk::Int

                 , vcpus::Int, status::String

                 , pnode::String, snode::String

                 , pdx::Types.Ndx, sdx::Types.Ndx)

    in

      case inst of

        Nothing -> False

        Just (_, i) ->

            (Instance.name i == name &&

             Instance.vcpus i == vcpus &&

             Instance.mem i == mem &&

             Instance.pNode i == pdx &&

             Instance.sNode i == (if null snode

                                  then Node.noSecondary

                                  else rsdx) &&

             isNothing fail1)

prop_Text_Load_InstanceFail ktn fields =

    length fields /= 8 ==> isNothing $ Text.loadInst ktn fields

prop_Text_Load_Node name tm nm fm td fd tc fo =

    let conv v = if v < 0

                    then "?"

                    else show v

        tm_s = conv tm

        nm_s = conv nm

        fm_s = conv fm

        td_s = conv td

        fd_s = conv fd

        tc_s = conv tc

        fo_s = if fo

               then "Y"

               else "N"

        any_broken = any (< 0) [tm, nm, fm, td, fd, tc]

    in case Text.loadNode [name, tm_s, nm_s, fm_s, td_s, fd_s, tc_s, fo_s] of

         Nothing -> False

         Just (name', node) ->

             if fo || any_broken

             then Node.offline node

             else Node.name node == name' && name' == name &&

                  Node.alias node == name &&

                  Node.tMem node == fromIntegral tm &&

                  Node.nMem node == nm &&

                  Node.fMem node == fm &&

                  Node.tDsk node == fromIntegral td &&

                  Node.fDsk node == fd &&

                  Node.tCpu node == fromIntegral tc

prop_Text_Load_NodeFail fields =

    length fields /= 8 ==> isNothing $ Text.loadNode fields

prop_Text_NodeLSIdempotent node =

    (Text.loadNode .

         Utils.sepSplit '|' . Text.serializeNode) n ==

    Just (Node.name n, n)

    -- override failN1 to what loadNode returns by default

    where n = node { Node.failN1 = True, Node.offline = False }

testText =

    [ run prop_Text_Load_Instance

    , run prop_Text_Load_InstanceFail

    , run prop_Text_Load_Node

    , run prop_Text_Load_NodeFail

    , run prop_Text_NodeLSIdempotent

    ]

-- Node tests

prop_Node_setAlias node name =

    Node.name newnode == Node.name node &&

    Node.alias newnode == name

    where _types = (node::Node.Node, name::String)

          newnode = Node.setAlias node name

prop_Node_setOffline node status =

    Node.offline newnode == status

    where newnode = Node.setOffline node status

prop_Node_setXmem node xm =

    Node.xMem newnode == xm

    where newnode = Node.setXmem node xm

prop_Node_setMcpu node mc =

    Node.mCpu newnode == mc

    where newnode = Node.setMcpu node mc

-- | Check that an instance add with too high memory or disk will be rejected

prop_Node_addPriFM node inst = Instance.mem inst >= Node.fMem node &&

                               not (Node.failN1 node)

                               ==>

                               case Node.addPri node inst'' of

                                 Types.OpFail Types.FailMem -> True

                                 _ -> False

    where _types = (node::Node.Node, inst::Instance.Instance)

          inst' = setInstanceSmallerThanNode node inst

          inst'' = inst' { Instance.mem = Instance.mem inst }

prop_Node_addPriFD node inst = Instance.dsk inst >= Node.fDsk node &&

                               not (Node.failN1 node)

                               ==>

                               case Node.addPri node inst'' of

                                 Types.OpFail Types.FailDisk -> True

                                 _ -> False

    where _types = (node::Node.Node, inst::Instance.Instance)

          inst' = setInstanceSmallerThanNode node inst

          inst'' = inst' { Instance.dsk = Instance.dsk inst }

prop_Node_addPriFC node inst = Instance.vcpus inst > Node.availCpu node &&

                               not (Node.failN1 node)

                               ==>

                               case Node.addPri node inst'' of

                                 Types.OpFail Types.FailCPU -> True

                                 _ -> False

    where _types = (node::Node.Node, inst::Instance.Instance)

          inst' = setInstanceSmallerThanNode node inst

          inst'' = inst' { Instance.vcpus = Instance.vcpus inst }

-- | Check that an instance add with too high memory or disk will be rejected

prop_Node_addSec node inst pdx =

    (Instance.mem inst >= (Node.fMem node - Node.rMem node) ||

     Instance.dsk inst >= Node.fDsk node) &&

    not (Node.failN1 node)

    ==> isFailure (Node.addSec node inst pdx)

        where _types = (node::Node.Node, inst::Instance.Instance, pdx::Int)

newtype SmallRatio = SmallRatio Double deriving Show

instance Arbitrary SmallRatio where

    arbitrary = do

      v <- choose (0, 1)

      return $ SmallRatio v

-- | Check mdsk setting

prop_Node_setMdsk node mx =

    Node.loDsk node' >= 0 &&

    fromIntegral (Node.loDsk node') <= Node.tDsk node &&

    Node.availDisk node' >= 0 &&

    Node.availDisk node' <= Node.fDsk node' &&

    fromIntegral (Node.availDisk node') <= Node.tDsk node' &&

    Node.mDsk node' == mx'

    where _types = (node::Node.Node, mx::SmallRatio)

          node' = Node.setMdsk node mx'

          SmallRatio mx' = mx

-- Check tag maps

prop_Node_tagMaps_idempotent tags =

    Node.delTags (Node.addTags m tags) tags == m

    where m = Data.Map.empty

prop_Node_tagMaps_reject tags =

    not (null tags) ==>

    any (\t -> Node.rejectAddTags m [t]) tags

    where m = Node.addTags Data.Map.empty tags

prop_Node_showField node =

  forAll (elements Node.defaultFields) $ \ field ->

  fst (Node.showHeader field) /= Types.unknownField &&

  Node.showField node field /= Types.unknownField

testNode =

    [ run prop_Node_setAlias

    , run prop_Node_setOffline

    , run prop_Node_setMcpu

    , run prop_Node_setXmem

    , run prop_Node_addPriFM

    , run prop_Node_addPriFD

    , run prop_Node_addPriFC

    , run prop_Node_addSec

    , run prop_Node_setMdsk

    , run prop_Node_tagMaps_idempotent

    , run prop_Node_tagMaps_reject

    , run prop_Node_showField

    ]

-- Cluster tests

-- | Check that the cluster score is close to zero for a homogeneous cluster

prop_Score_Zero node count =

    (not (Node.offline node) && not (Node.failN1 node) && (count > 0) &&

     (Node.tDsk node > 0) && (Node.tMem node > 0)) ==>

    let fn = Node.buildPeers node Container.empty

        nlst = zip [1..] $ replicate count fn::[(Types.Ndx, Node.Node)]

        nl = Container.fromAssocList nlst

        score = Cluster.compCV nl

    -- we can't say == 0 here as the floating point errors accumulate;

    -- this should be much lower than the default score in CLI.hs

    in score <= 1e-15

-- | Check that cluster stats are sane

prop_CStats_sane node count =

    (not (Node.offline node) && not (Node.failN1 node) && (count > 0) &&

     (Node.availDisk node > 0) && (Node.availMem node > 0)) ==>

    let fn = Node.buildPeers node Container.empty

        nlst = zip [1..] $ replicate count fn::[(Types.Ndx, Node.Node)]

        nl = Container.fromAssocList nlst

        cstats = Cluster.totalResources nl

    in Cluster.csAdsk cstats >= 0 &&

       Cluster.csAdsk cstats <= Cluster.csFdsk cstats

-- | Check that one instance is allocated correctly, without

-- rebalances needed

prop_ClusterAlloc_sane node inst =

    forAll (choose (5, 20)) $ \count ->

    not (Node.offline node)

            && not (Node.failN1 node)

            && Node.availDisk node > 0

            && Node.availMem node > 0

            ==>

    let nl = makeSmallCluster node count

        il = Container.empty

        rqnodes = 2

        inst' = setInstanceSmallerThanNode node inst

    in case Cluster.tryAlloc nl il inst' rqnodes of

         Types.Bad _ -> False

         Types.Ok (_, _, sols3) ->

             case sols3 of

               [] -> False

               (_, (xnl, xi, _)):[] ->

                   let cv = Cluster.compCV xnl

                       il' = Container.add (Instance.idx xi) xi il

                       tbl = Cluster.Table xnl il' cv []

                   in not (canBalance tbl True False)

               _ -> False

-- | Checks that on a 2-5 node cluster, we can allocate a random

-- instance spec via tiered allocation (whatever the original instance

-- spec), on either one or two nodes

prop_ClusterCanTieredAlloc node inst =

    forAll (choose (2, 5)) $ \count ->

    forAll (choose (1, 2)) $ \rqnodes ->

    not (Node.offline node)

            && not (Node.failN1 node)

            && isNodeBig node 4

            ==>

    let nl = makeSmallCluster node count

        il = Container.empty

    in case Cluster.tieredAlloc nl il inst rqnodes [] of

         Types.Bad _ -> False

         Types.Ok (_, _, il', ixes) -> not (null ixes) &&

                                      IntMap.size il' == length ixes

-- | Checks that on a 4-8 node cluster, once we allocate an instance,

-- we can also evacuate it

prop_ClusterAllocEvac node inst =

    forAll (choose (4, 8)) $ \count ->

    not (Node.offline node)

            && not (Node.failN1 node)

            && isNodeBig node 4

            ==>

    let nl = makeSmallCluster node count

        il = Container.empty

        rqnodes = 2

        inst' = setInstanceSmallerThanNode node inst

    in case Cluster.tryAlloc nl il inst' rqnodes of

         Types.Bad _ -> False

         Types.Ok (_, _, sols3) ->

             case sols3 of

               [] -> False

               (_, (xnl, xi, _)):[] ->

                   let sdx = Instance.sNode xi

                       il' = Container.add (Instance.idx xi) xi il

                   in case Cluster.tryEvac xnl il' [sdx] of

                        Just _ -> True

                        _ -> False

               _ -> False

-- | Check that allocating multiple instances on a cluster, then

-- adding an empty node, results in a valid rebalance

prop_ClusterAllocBalance node =

    forAll (choose (3, 5)) $ \count ->

    not (Node.offline node)

            && not (Node.failN1 node)

            && isNodeBig node 4

            && not (isNodeBig node 8)

            ==>

    let nl = makeSmallCluster node count

        (hnode, nl') = IntMap.deleteFindMax nl

        il = Container.empty

        rqnodes = 2

        i_templ = createInstance Types.unitMem Types.unitDsk Types.unitCpu

    in case Cluster.iterateAlloc nl' il i_templ rqnodes [] of

         Types.Bad _ -> False

         Types.Ok (_, xnl, il', _) ->

                   let ynl = Container.add (Node.idx hnode) hnode xnl

                       cv = Cluster.compCV ynl

                       tbl = Cluster.Table ynl il' cv []

                   in canBalance tbl True False

testCluster =

    [ run prop_Score_Zero

    , run prop_CStats_sane

    , run prop_ClusterAlloc_sane

    , run prop_ClusterCanTieredAlloc

    , run prop_ClusterAllocEvac

    , run prop_ClusterAllocBalance

    ]

-- | Check that opcode serialization is idempotent

prop_OpCodes_serialization op =

  case J.readJSON (J.showJSON op) of

    J.Error _ -> False

    J.Ok op' -> op == op'

  where _types = op::OpCodes.OpCode

testOpCodes =

  [ run prop_OpCodes_serialization

  ]

-- | Check that (queued) job\/opcode status serialization is idempotent

prop_OpStatus_serialization os =

  case J.readJSON (J.showJSON os) of

    J.Error _ -> False

    J.Ok os' -> os == os'

  where _types = os::Jobs.OpStatus

prop_JobStatus_serialization js =

  case J.readJSON (J.showJSON js) of

    J.Error _ -> False

    J.Ok js' -> js == js'

  where _types = js::Jobs.JobStatus

testJobs =

  [ run prop_OpStatus_serialization

  , run prop_JobStatus_serialization

  ]

-- | Loader tests

prop_Loader_lookupNode ktn inst node =

  isJust (Loader.lookupNode ktn inst node) == (node `elem` names)

    where names = map fst ktn

prop_Loader_lookupInstance kti inst =

  isJust (Loader.lookupInstance kti inst) == (inst `elem` names)

    where names = map fst kti

prop_Loader_lookupInstanceIdx kti inst =

  case (Loader.lookupInstance kti inst,

        findIndex (\p -> fst p == inst) kti) of

    (Nothing, Nothing) -> True

    (Just idx, Just ex) -> idx == snd (kti !! ex)

    _ -> False

prop_Loader_assignIndices enames =

  length nassoc == length enames &&

  length kt == length enames &&

  (if not (null enames)

   then maximum (map fst kt) == length enames - 1

   else True)

  where (nassoc, kt) = Loader.assignIndices enames

        _types = enames::[(String, Node.Node)]

-- | Checks that the number of primary instances recorded on the nodes

-- is zero

prop_Loader_mergeData ns =

  let na = map (\n -> (Node.idx n, n)) ns

  in case Loader.mergeData [] [] [] (na, [], []) of

    Types.Bad _ -> False

    Types.Ok (nl, il, _) ->

      let nodes = Container.elems nl

          instances = Container.elems il

      in (sum . map (length . Node.pList)) nodes == 0 &&

         null instances

testLoader =

  [ run prop_Loader_lookupNode

  , run prop_Loader_lookupInstance

  , run prop_Loader_lookupInstanceIdx

  , run prop_Loader_assignIndices

  , run prop_Loader_mergeData

  ]