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{-# LANGUAGE TemplateHaskell #-}

{-# OPTIONS_GHC -fno-warn-orphans #-}

{-| Unittests for ganeti-htools.

-}

{-

Copyright (C) 2009, 2010, 2011, 2012 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

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(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

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-}

module Test.Ganeti.HTools.Cluster (testHTools_Cluster) where

import Test.QuickCheck hiding (Result)

import qualified Data.IntMap as IntMap

import Data.Maybe

import Test.Ganeti.TestHelper

import Test.Ganeti.TestCommon

import Test.Ganeti.TestHTools

import Test.Ganeti.HTools.Instance ( genInstanceSmallerThanNode

                                   , genInstanceMaybeBiggerThanNode )

import Test.Ganeti.HTools.Node (genOnlineNode, genNode)

import Ganeti.BasicTypes

import qualified Ganeti.HTools.Backend.IAlloc as IAlloc

import qualified Ganeti.HTools.Cluster as Cluster

import qualified Ganeti.HTools.Container as Container

import qualified Ganeti.HTools.Group as Group

import qualified Ganeti.HTools.Instance as Instance

import qualified Ganeti.HTools.Node as Node

import qualified Ganeti.HTools.Types as Types

{-# ANN module "HLint: ignore Use camelCase" #-}

-- * Helpers

-- | Make a small cluster, both nodes and instances.

makeSmallEmptyCluster :: Node.Node -> Int -> Instance.Instance

                      -> (Node.List, Instance.List, Instance.Instance)

makeSmallEmptyCluster node count inst =

  (makeSmallCluster node count, Container.empty,

   setInstanceSmallerThanNode node inst)

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

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

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

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

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

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

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

-- | Assigns a new fresh instance to a cluster; this is not

-- allocation, so no resource checks are done.

assignInstance :: Node.List -> Instance.List -> Instance.Instance ->

                  Types.Idx -> Types.Idx ->

                  (Node.List, Instance.List)

assignInstance nl il inst pdx sdx =

  let pnode = Container.find pdx nl

      snode = Container.find sdx nl

      maxiidx = if Container.null il

                  then 0

                  else fst (Container.findMax il) + 1

      inst' = inst { Instance.idx = maxiidx,

                     Instance.pNode = pdx, Instance.sNode = sdx }

      pnode' = Node.setPri pnode inst'

      snode' = Node.setSec snode inst'

      nl' = Container.addTwo pdx pnode' sdx snode' nl

      il' = Container.add maxiidx inst' il

  in (nl', il')

-- | Checks if an instance is mirrored.

isMirrored :: Instance.Instance -> Bool

isMirrored = (/= Types.MirrorNone) . Instance.mirrorType

-- | Returns the possible change node types for a disk template.

evacModeOptions :: Types.MirrorType -> [Types.EvacMode]

evacModeOptions Types.MirrorNone     = []

evacModeOptions Types.MirrorInternal = [minBound..maxBound] -- DRBD can do all

evacModeOptions Types.MirrorExternal = [Types.ChangePrimary, Types.ChangeAll]

-- * Test cases

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

-- cluster.

prop_Score_Zero :: Node.Node -> Property

prop_Score_Zero node =

  forAll (choose (1, 1024)) $ \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 = replicate count fn

      score = Cluster.compCVNodes nlst

  -- 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-12

-- | Check that cluster stats are sane.

prop_CStats_sane :: Property

prop_CStats_sane =

  forAll (choose (1, 1024)) $ \count ->

  forAll genOnlineNode $ \node ->

  let fn = Node.buildPeers node Container.empty

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

      nl = Container.fromList 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_Alloc_sane :: Instance.Instance -> Property

prop_Alloc_sane inst =

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

  forAll genOnlineNode $ \node ->

  let (nl, il, inst') = makeSmallEmptyCluster node count inst

      reqnodes = Instance.requiredNodes $ Instance.diskTemplate inst

  in case Cluster.genAllocNodes defGroupList nl reqnodes True >>=

     Cluster.tryAlloc nl il inst' of

       Bad msg -> failTest msg

       Ok as ->

         case Cluster.asSolution as of

           Nothing -> failTest "Failed to allocate, empty solution"

           Just (xnl, xi, _, cv) ->

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

                 tbl = Cluster.Table xnl il' cv []

             in printTestCase "Cluster can be balanced after allocation"

                  (not (canBalance tbl True True False)) .&&.

                printTestCase "Solution score differs from actual node list:"

                  (Cluster.compCV xnl ==? cv)

-- | Check that multiple instances can allocated correctly, without

-- rebalances needed.

prop_IterateAlloc_sane :: Instance.Instance -> Property

prop_IterateAlloc_sane inst =

  forAll (choose (5, 10)) $ \count ->

  forAll genOnlineNode $ \node ->

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

  let (nl, il, inst') = makeSmallEmptyCluster node count inst

      reqnodes = Instance.requiredNodes $ Instance.diskTemplate inst

      allocnodes = Cluster.genAllocNodes defGroupList nl reqnodes True

  in case allocnodes >>= \allocnodes' ->

     Cluster.iterateAlloc nl il (Just limit) inst' allocnodes' [] [] of

       Bad msg -> failTest msg

       Ok (_, xnl, xil, _, _) ->

         let old_score = Cluster.compCV xnl

             tbl = Cluster.Table xnl xil old_score []

         in case Cluster.tryBalance tbl True True False 0 1e-4 of

              Nothing -> passTest

              Just (Cluster.Table ynl _ new_score plcs) ->

                -- note that with a "min_gain" of zero, sometime

                -- rounding errors can trigger a rebalance that

                -- improves the score by e.g. 2e-14; in order to

                -- prevent such no-real-change moves from happening,

                -- we check for a min-gain of 1e-9

                -- FIXME: correct rebalancing to not do no-ops

                printTestCase

                  ("Cluster can be balanced after allocation\n" ++

                   " old cluster (score " ++ show old_score ++

                   "):\n" ++ Cluster.printNodes xnl [] ++

                   " new cluster (score " ++ show new_score ++

                   "):\n" ++ Cluster.printNodes ynl [] ++

                   "placements:\n" ++ show plcs ++ "\nscore delta: " ++

                   show (old_score - new_score))

                  (old_score - new_score < 1e-9)

-- | 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. Furthermore, we test that

-- computed allocation statistics are correct.

prop_CanTieredAlloc :: Property

prop_CanTieredAlloc =

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

  forAll (genOnlineNode `suchThat` isNodeBig 4) $ \node ->

  forAll (genInstanceMaybeBiggerThanNode node) $ \inst ->

  let nl = makeSmallCluster node count

      il = Container.empty

      rqnodes = Instance.requiredNodes $ Instance.diskTemplate inst

      allocnodes = Cluster.genAllocNodes defGroupList nl rqnodes True

  in case allocnodes >>= \allocnodes' ->

    Cluster.tieredAlloc nl il (Just 5) inst allocnodes' [] [] of

       Bad msg -> failTest $ "Failed to tiered alloc: " ++ msg

       Ok (_, nl', il', ixes, cstats) ->

         let (ai_alloc, ai_pool, ai_unav) =

               Cluster.computeAllocationDelta

                (Cluster.totalResources nl)

                (Cluster.totalResources nl')

             all_nodes fn = sum $ map fn (Container.elems nl)

             all_res fn = sum $ map fn [ai_alloc, ai_pool, ai_unav]

         in conjoin

            [ printTestCase "No instances allocated" $ not (null ixes)

            , IntMap.size il' ==? length ixes

            , length ixes     ==? length cstats

            , all_res Types.allocInfoVCpus ==? all_nodes Node.hiCpu

            , all_res Types.allocInfoNCpus ==? all_nodes Node.tCpu

            , all_res Types.allocInfoMem   ==? truncate (all_nodes Node.tMem)

            , all_res Types.allocInfoDisk  ==? truncate (all_nodes Node.tDsk)

            ]

-- | Helper function to create a cluster with the given range of nodes

-- and allocate an instance on it.

genClusterAlloc :: Int -> Node.Node -> Instance.Instance

                -> Result (Node.List, Instance.List, Instance.Instance)

genClusterAlloc count node inst =

  let nl = makeSmallCluster node count

      reqnodes = Instance.requiredNodes $ Instance.diskTemplate inst

  in case Cluster.genAllocNodes defGroupList nl reqnodes True >>=

     Cluster.tryAlloc nl Container.empty inst of

       Bad msg -> Bad $ "Can't allocate: " ++ msg

       Ok as ->

         case Cluster.asSolution as of

           Nothing -> Bad "Empty solution?"

           Just (xnl, xi, _, _) ->

             let xil = Container.add (Instance.idx xi) xi Container.empty

             in Ok (xnl, xil, xi)

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

-- we can also relocate it.

prop_AllocRelocate :: Property

prop_AllocRelocate =

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

  forAll (genOnlineNode `suchThat` isNodeBig 4) $ \node ->

  forAll (genInstanceSmallerThanNode node `suchThat` isMirrored) $ \inst ->

  case genClusterAlloc count node inst of

    Bad msg -> failTest msg

    Ok (nl, il, inst') ->

      case IAlloc.processRelocate defGroupList nl il

             (Instance.idx inst) 1

             [(if Instance.diskTemplate inst' == Types.DTDrbd8

                 then Instance.sNode

                 else Instance.pNode) inst'] of

        Ok _ -> passTest

        Bad msg -> failTest $ "Failed to relocate: " ++ msg

-- | Helper property checker for the result of a nodeEvac or

-- changeGroup operation.

check_EvacMode :: Group.Group -> Instance.Instance

               -> Result (Node.List, Instance.List, Cluster.EvacSolution)

               -> Property

check_EvacMode grp inst result =

  case result of

    Bad msg -> failTest $ "Couldn't evacuate/change group:" ++ msg

    Ok (_, _, es) ->

      let moved = Cluster.esMoved es

          failed = Cluster.esFailed es

          opcodes = not . null $ Cluster.esOpCodes es

      in conjoin

           [ failmsg ("'failed' not empty: " ++ show failed) (null failed)

           , failmsg "'opcodes' is null" opcodes

           , case moved of

               [(idx', gdx, _)] ->

                 failmsg "invalid instance moved" (idx == idx') .&&.

                 failmsg "wrong target group" (gdx == Group.idx grp)

               v -> failmsg  ("invalid solution: " ++ show v) False

           ]

  where failmsg :: String -> Bool -> Property

        failmsg msg = printTestCase ("Failed to evacuate: " ++ msg)

        idx = Instance.idx inst

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

-- we can also node-evacuate it.

prop_AllocEvacuate :: Property

prop_AllocEvacuate =

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

  forAll (genOnlineNode `suchThat` isNodeBig 4) $ \node ->

  forAll (genInstanceSmallerThanNode node `suchThat` isMirrored) $ \inst ->

  case genClusterAlloc count node inst of

    Bad msg -> failTest msg

    Ok (nl, il, inst') ->

      conjoin . map (\mode -> check_EvacMode defGroup inst' $

                              Cluster.tryNodeEvac defGroupList nl il mode

                                [Instance.idx inst']) .

                              evacModeOptions .

                              Instance.mirrorType $ inst'

-- | Checks that on a 4-8 node cluster with two node groups, once we

-- allocate an instance on the first node group, we can also change

-- its group.

prop_AllocChangeGroup :: Property

prop_AllocChangeGroup =

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

  forAll (genOnlineNode `suchThat` isNodeBig 4) $ \node ->

  forAll (genInstanceSmallerThanNode node `suchThat` isMirrored) $ \inst ->

  case genClusterAlloc count node inst of

    Bad msg -> failTest msg

    Ok (nl, il, inst') ->

      -- we need to add a second node group and nodes to the cluster

      let nl2 = Container.elems $ makeSmallCluster node count

          grp2 = Group.setIdx defGroup (Group.idx defGroup + 1)

          maxndx = maximum . map Node.idx $ nl2

          nl3 = map (\n -> n { Node.group = Group.idx grp2

                             , Node.idx = Node.idx n + maxndx }) nl2

          nl4 = Container.fromList . map (\n -> (Node.idx n, n)) $ nl3

          gl' = Container.add (Group.idx grp2) grp2 defGroupList

          nl' = IntMap.union nl nl4

      in check_EvacMode grp2 inst' $

         Cluster.tryChangeGroup gl' nl' il [] [Instance.idx inst']

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

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

prop_AllocBalance :: Property

prop_AllocBalance =

  forAll (genNode (Just 5) (Just 128)) $ \node ->

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

  not (Node.offline node) && not (Node.failN1 node) ==>

  let nl = makeSmallCluster node count

      hnode = snd $ IntMap.findMax nl

      nl' = IntMap.deleteMax nl

      il = Container.empty

      allocnodes = Cluster.genAllocNodes defGroupList nl' 2 True

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

  in case allocnodes >>= \allocnodes' ->

    Cluster.iterateAlloc nl' il (Just 5) i_templ allocnodes' [] [] of

       Bad msg -> failTest $ "Failed to allocate: " ++ msg

       Ok (_, _, _, [], _) -> failTest "Failed to allocate: no instances"

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

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

             cv = Cluster.compCV ynl

             tbl = Cluster.Table ynl il' cv []

         in printTestCase "Failed to rebalance" $

            canBalance tbl True True False

-- | Checks consistency.

prop_CheckConsistency :: Node.Node -> Instance.Instance -> Bool

prop_CheckConsistency node inst =

  let nl = makeSmallCluster node 3

      (node1, node2, node3) =

        case Container.elems nl of

          [a, b, c] -> (a, b, c)

          l -> error $ "Invalid node list out of makeSmallCluster/3: " ++

               show l

      node3' = node3 { Node.group = 1 }

      nl' = Container.add (Node.idx node3') node3' nl

      inst1 = Instance.setBoth inst (Node.idx node1) (Node.idx node2)

      inst2 = Instance.setBoth inst (Node.idx node1) Node.noSecondary

      inst3 = Instance.setBoth inst (Node.idx node1) (Node.idx node3)

      ccheck = Cluster.findSplitInstances nl' . Container.fromList

  in null (ccheck [(0, inst1)]) &&

     null (ccheck [(0, inst2)]) &&

     (not . null $ ccheck [(0, inst3)])

-- | For now, we only test that we don't lose instances during the split.

prop_SplitCluster :: Node.Node -> Instance.Instance -> Property

prop_SplitCluster node inst =

  forAll (choose (0, 100)) $ \icnt ->

  let nl = makeSmallCluster node 2

      (nl', il') = foldl (\(ns, is) _ -> assignInstance ns is inst 0 1)

                   (nl, Container.empty) [1..icnt]

      gni = Cluster.splitCluster nl' il'

  in sum (map (Container.size . snd . snd) gni) == icnt &&

     all (\(guuid, (nl'', _)) -> all ((== guuid) . Node.group)

                                 (Container.elems nl'')) gni

-- | Helper function to check if we can allocate an instance on a

-- given node list. Successful allocation is denoted by 'Nothing',

-- otherwise the 'Just' value will contain the error message.

canAllocOn :: Node.List -> Int -> Instance.Instance -> Maybe String

canAllocOn nl reqnodes inst =

  case Cluster.genAllocNodes defGroupList nl reqnodes True >>=

       Cluster.tryAlloc nl Container.empty inst of

       Bad msg -> Just $ "Can't allocate: " ++ msg

       Ok as ->

         case Cluster.asSolution as of

           Nothing -> Just $ "No allocation solution; failures: " ++

                      show (Cluster.collapseFailures $ Cluster.asFailures as)

           Just _ -> Nothing

-- | Checks that allocation obeys minimum and maximum instance

-- policies. The unittest generates a random node, duplicates it /count/

-- times, and generates a random instance that can be allocated on

-- this mini-cluster; it then checks that after applying a policy that

-- the instance doesn't fits, the allocation fails.

prop_AllocPolicy :: Property

prop_AllocPolicy =

  forAll genOnlineNode $ \node ->

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

  forAll (genInstanceSmallerThanNode node) $ \inst ->

  forAll (arbitrary `suchThat`

          (isBad . flip (Instance.instMatchesPolicy inst)

           (Node.exclStorage node))) $ \ipol ->

  let rqn = Instance.requiredNodes $ Instance.diskTemplate inst

      node' = Node.setPolicy ipol node

      nl = makeSmallCluster node' count

  in printTestCase "Allocation check:"

       (isNothing (canAllocOn (makeSmallCluster node count) rqn inst)) .&&.

     printTestCase "Policy failure check:" (isJust $ canAllocOn nl rqn inst)

testSuite "HTools/Cluster"

            [ 'prop_Score_Zero

            , 'prop_CStats_sane

            , 'prop_Alloc_sane

            , 'prop_IterateAlloc_sane

            , 'prop_CanTieredAlloc

            , 'prop_AllocRelocate

            , 'prop_AllocEvacuate

            , 'prop_AllocChangeGroup

            , 'prop_AllocBalance

            , 'prop_CheckConsistency

            , 'prop_SplitCluster

            , 'prop_AllocPolicy

            ]