Synnefo » snf-ganeti

{-| Implementation of the Ganeti Query2 server.

-}

{-

Copyright (C) 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 Ganeti.Query.Server

  ( main

  , checkMain

  , prepMain

  ) where

import Control.Applicative

import Control.Concurrent

import Control.Exception

import Control.Monad (forever, when, zipWithM, liftM)

import Data.Bits (bitSize)

import qualified Data.Set as Set (toList)

import Data.IORef

import qualified Text.JSON as J

import Text.JSON (encode, showJSON, JSValue(..))

import System.Info (arch)

import qualified Ganeti.Constants as C

import qualified Ganeti.ConstantUtils as ConstantUtils (unFrozenSet)

import Ganeti.Errors

import qualified Ganeti.Path as Path

import Ganeti.Daemon

import Ganeti.Objects

import qualified Ganeti.Config as Config

import Ganeti.ConfigReader

import Ganeti.BasicTypes

import Ganeti.JQueue

import Ganeti.JQScheduler

import Ganeti.Logging

import Ganeti.Luxi

import qualified Ganeti.Query.Language as Qlang

import qualified Ganeti.Query.Cluster as QCluster

import Ganeti.Path (queueDir, jobQueueLockFile)

import Ganeti.Query.Query

import Ganeti.Query.Filter (makeSimpleFilter)

import Ganeti.Types

import qualified Ganeti.UDSServer as U

import Ganeti.Utils (lockFile, exitIfBad, watchFile)

import qualified Ganeti.Version as Version

-- | Helper for classic queries.

handleClassicQuery :: ConfigData      -- ^ Cluster config

                   -> Qlang.ItemType  -- ^ Query type

                   -> [Either String Integer] -- ^ Requested names

                                              -- (empty means all)

                   -> [String]        -- ^ Requested fields

                   -> Bool            -- ^ Whether to do sync queries or not

                   -> IO (GenericResult GanetiException JSValue)

handleClassicQuery _ _ _ _ True =

  return . Bad $ OpPrereqError "Sync queries are not allowed" ECodeInval

handleClassicQuery cfg qkind names fields _ = do

  let flt = makeSimpleFilter (nameField qkind) names

  qr <- query cfg True (Qlang.Query qkind fields flt)

  return $ showJSON <$> (qr >>= queryCompat)

-- | Minimal wrapper to handle the missing config case.

handleCallWrapper :: MVar () -> JQStatus ->  Result ConfigData 

                     -> LuxiOp -> IO (ErrorResult JSValue)

handleCallWrapper _ _ (Bad msg) _ =

  return . Bad . ConfigurationError $

           "I do not have access to a valid configuration, cannot\

           \ process queries: " ++ msg

handleCallWrapper qlock qstat (Ok config) op = handleCall qlock qstat config op

-- | Actual luxi operation handler.

handleCall :: MVar () -> JQStatus 

              -> ConfigData -> LuxiOp -> IO (ErrorResult JSValue)

handleCall _ _ cdata QueryClusterInfo =

  let cluster = configCluster cdata

      master = QCluster.clusterMasterNodeName cdata

      hypervisors = clusterEnabledHypervisors cluster

      diskTemplates = clusterEnabledDiskTemplates cluster

      def_hv = case hypervisors of

                 x:_ -> showJSON x

                 [] -> JSNull

      bits = show (bitSize (0::Int)) ++ "bits"

      arch_tuple = [bits, arch]

      obj = [ ("software_version", showJSON C.releaseVersion)

            , ("protocol_version", showJSON C.protocolVersion)

            , ("config_version", showJSON C.configVersion)

            , ("os_api_version", showJSON . maximum .

                                 Set.toList . ConstantUtils.unFrozenSet $

                                 C.osApiVersions)

            , ("export_version", showJSON C.exportVersion)

            , ("vcs_version", showJSON Version.version)

            , ("architecture", showJSON arch_tuple)

            , ("name", showJSON $ clusterClusterName cluster)

            , ("master", showJSON (case master of

                                     Ok name -> name

                                     _ -> undefined))

            , ("default_hypervisor", def_hv)

            , ("enabled_hypervisors", showJSON hypervisors)

            , ("hvparams", showJSON $ clusterHvparams cluster)

            , ("os_hvp", showJSON $ clusterOsHvp cluster)

            , ("beparams", showJSON $ clusterBeparams cluster)

            , ("osparams", showJSON $ clusterOsparams cluster)

            , ("ipolicy", showJSON $ clusterIpolicy cluster)

            , ("nicparams", showJSON $ clusterNicparams cluster)

            , ("ndparams", showJSON $ clusterNdparams cluster)

            , ("diskparams", showJSON $ clusterDiskparams cluster)

            , ("candidate_pool_size",

               showJSON $ clusterCandidatePoolSize cluster)

            , ("master_netdev",  showJSON $ clusterMasterNetdev cluster)

            , ("master_netmask", showJSON $ clusterMasterNetmask cluster)

            , ("use_external_mip_script",

               showJSON $ clusterUseExternalMipScript cluster)

            , ("volume_group_name",

               maybe JSNull showJSON (clusterVolumeGroupName cluster))

            , ("drbd_usermode_helper",

               maybe JSNull showJSON (clusterDrbdUsermodeHelper cluster))

            , ("file_storage_dir", showJSON $ clusterFileStorageDir cluster)

            , ("shared_file_storage_dir",

               showJSON $ clusterSharedFileStorageDir cluster)

            , ("maintain_node_health",

               showJSON $ clusterMaintainNodeHealth cluster)

            , ("ctime", showJSON $ clusterCtime cluster)

            , ("mtime", showJSON $ clusterMtime cluster)

            , ("uuid", showJSON $ clusterUuid cluster)

            , ("tags", showJSON $ clusterTags cluster)

            , ("uid_pool", showJSON $ clusterUidPool cluster)

            , ("default_iallocator",

               showJSON $ clusterDefaultIallocator cluster)

            , ("default_iallocator_params",

              showJSON $ clusterDefaultIallocatorParams cluster)

            , ("reserved_lvs", showJSON $ clusterReservedLvs cluster)

            , ("primary_ip_version",

               showJSON . ipFamilyToVersion $ clusterPrimaryIpFamily cluster)

            , ("prealloc_wipe_disks",

               showJSON $ clusterPreallocWipeDisks cluster)

            , ("hidden_os", showJSON $ clusterHiddenOs cluster)

            , ("blacklisted_os", showJSON $ clusterBlacklistedOs cluster)

            , ("enabled_disk_templates", showJSON diskTemplates)

            ]

  in case master of

    Ok _ -> return . Ok . J.makeObj $ obj

    Bad ex -> return $ Bad ex

handleCall _ _ cfg (QueryTags kind name) = do

  let tags = case kind of

               TagKindCluster  -> Ok . clusterTags $ configCluster cfg

               TagKindGroup    -> groupTags <$> Config.getGroup    cfg name

               TagKindNode     -> nodeTags  <$> Config.getNode     cfg name

               TagKindInstance -> instTags  <$> Config.getInstance cfg name

               TagKindNetwork  -> Bad $ OpPrereqError

                                        "Network tag is not allowed"

                                        ECodeInval

  return (J.showJSON <$> tags)

handleCall _ _ cfg (Query qkind qfields qfilter) = do

  result <- query cfg True (Qlang.Query qkind qfields qfilter)

  return $ J.showJSON <$> result

handleCall _ _ _ (QueryFields qkind qfields) = do

  let result = queryFields (Qlang.QueryFields qkind qfields)

  return $ J.showJSON <$> result

handleCall _ _ cfg (QueryNodes names fields lock) =

  handleClassicQuery cfg (Qlang.ItemTypeOpCode Qlang.QRNode)

    (map Left names) fields lock

handleCall _ _ cfg (QueryInstances names fields lock) =

  handleClassicQuery cfg (Qlang.ItemTypeOpCode Qlang.QRInstance)

    (map Left names) fields lock

handleCall _ _ cfg (QueryGroups names fields lock) =

  handleClassicQuery cfg (Qlang.ItemTypeOpCode Qlang.QRGroup)

    (map Left names) fields lock

handleCall _ _ cfg (QueryJobs names fields) =

  handleClassicQuery cfg (Qlang.ItemTypeLuxi Qlang.QRJob)

    (map (Right . fromIntegral . fromJobId) names)  fields False

handleCall _ _ cfg (QueryNetworks names fields lock) =

  handleClassicQuery cfg (Qlang.ItemTypeOpCode Qlang.QRNetwork)

    (map Left names) fields lock

handleCall qlock qstat cfg (SubmitJobToDrainedQueue ops) =

  do

    let mcs = Config.getMasterCandidates cfg

    jobid <- allocateJobId mcs qlock

    case jobid of

      Bad s -> return . Bad . GenericError $ s

      Ok jid -> do

        ts <- currentTimestamp

        job <- liftM (setReceivedTimestamp ts)

                 $ queuedJobFromOpCodes jid ops

        qDir <- queueDir

        write_result <- writeJobToDisk qDir job

        case write_result of

          Bad s -> return . Bad . GenericError $ s

          Ok () -> do

            _ <- replicateManyJobs qDir mcs [job]

            _ <- forkIO $ enqueueNewJobs qstat [job]

            return . Ok . showJSON . fromJobId $ jid

handleCall qlock qstat cfg (SubmitJob ops) =

  do

    open <- isQueueOpen

    if not open

       then return . Bad . GenericError $ "Queue drained"

       else handleCall qlock qstat cfg (SubmitJobToDrainedQueue ops)

handleCall qlock qstat cfg (SubmitManyJobs lops) =

  do

    open <- isQueueOpen

    if not open

      then return . Bad . GenericError $ "Queue drained"

      else do

        let mcs = Config.getMasterCandidates cfg

        result_jobids <- allocateJobIds mcs qlock (length lops)

        case result_jobids of

          Bad s -> return . Bad . GenericError $ s

          Ok jids -> do

            ts <- currentTimestamp

            jobs <- liftM (map $ setReceivedTimestamp ts)

                      $ zipWithM queuedJobFromOpCodes jids lops

            qDir <- queueDir

            write_results <- mapM (writeJobToDisk qDir) jobs

            let annotated_results = zip write_results jobs

                succeeded = map snd $ filter (isOk . fst) annotated_results

            when (any isBad write_results) . logWarning

              $ "Writing some jobs failed " ++ show annotated_results

            replicateManyJobs qDir mcs succeeded

            _ <- forkIO $ enqueueNewJobs qstat succeeded

            return . Ok . JSArray

              . map (\(res, job) ->

                      if isOk res

                        then showJSON (True, fromJobId $ qjId job)

                        else showJSON (False, genericResult id (const "") res))

              $ annotated_results

handleCall _ _ cfg (WaitForJobChange jid fields prev_job prev_log tmout) = do

  let compute_fn = computeJobUpdate cfg jid fields prev_log 

  qDir <- queueDir

  -- verify if the job is finalized, and return immediately in this case

  jobresult <- loadJobFromDisk qDir False jid

  case jobresult of

    Ok (job, _) | not (jobFinalized job) -> do

      let jobfile = liveJobFile qDir jid

      answer <- watchFile jobfile (min tmout C.luxiWfjcTimeout)

                  (prev_job, JSArray []) compute_fn

      return . Ok $ showJSON answer

    _ -> liftM (Ok . showJSON) compute_fn

handleCall _ _ _ op =

  return . Bad $

    GenericError ("Luxi call '" ++ strOfOp op ++ "' not implemented")

{-# ANN handleCall "HLint: ignore Too strict if" #-}

-- | Query the status of a job and return the requested fields

-- and the logs newer than the given log number.

computeJobUpdate :: ConfigData -> JobId -> [String] -> JSValue 

                    -> IO (JSValue, JSValue)

computeJobUpdate cfg jid fields prev_log = do

  let sjid = show $ fromJobId jid

  logDebug $ "Inspecting fields " ++ show fields ++ " of job " ++ sjid

  let fromJSArray (JSArray xs) = xs

      fromJSArray _ = []

  let logFilter JSNull (JSArray _) = True

      logFilter (JSRational _ n) (JSArray (JSRational _ m:_)) = n < m

      logFilter _ _ = False

  let filterLogs n logs = JSArray (filter (logFilter n) (logs >>= fromJSArray))

  jobQuery <- handleClassicQuery cfg (Qlang.ItemTypeLuxi Qlang.QRJob)

                [Right . fromIntegral $ fromJobId jid] ("oplog" : fields) False

  let (rfields, rlogs) = case jobQuery of

        Ok (JSArray [JSArray (JSArray logs : answer)]) ->

          (answer, filterLogs prev_log logs)

        _ -> (map (const JSNull) fields, JSArray [])

  logDebug $ "Updates for job " ++ sjid ++ " are " ++ encode (rfields, rlogs)

  return (JSArray rfields, rlogs)

type LuxiConfig = (MVar (), JQStatus, ConfigReader)

luxiExec

    :: LuxiConfig

    -> LuxiOp

    -> IO (Bool, GenericResult GanetiException JSValue)

luxiExec (qlock, qstat, creader) args = do

  cfg <- creader

  result <- handleCallWrapper qlock qstat cfg args

  return (True, result)

luxiHandler :: LuxiConfig -> U.Handler LuxiOp JSValue

luxiHandler cfg = U.Handler { U.hParse         = decodeLuxiCall

                            , U.hInputLogShort = strOfOp

                            , U.hInputLogLong  = show

                            , U.hExec          = luxiExec cfg

                            }

-- | Logs an outgoing message.

logMsg

    :: (Show e, J.JSON e, MonadLog m)

    => U.Handler i o

    -> i                          -- ^ the received request (used for logging)

    -> GenericResult e J.JSValue  -- ^ A message to be sent

    -> m ()

logMsg handler req (Bad err) =

  logWarning $ "Failed to execute request "

               ++ U.hInputLogLong handler req ++ ": "

               ++ show err

logMsg handler req (Ok result) = do

  -- only log the first 2,000 chars of the result

  logDebug $ "Result (truncated): " ++ take 2000 (J.encode result)

  logInfo $ "Successfully handled " ++ U.hInputLogShort handler req

-- | Prepares an outgoing message.

prepareMsg

    :: (J.JSON e)

    => GenericResult e J.JSValue  -- ^ A message to be sent

    -> (Bool, J.JSValue)

prepareMsg (Bad err)   = (False, J.showJSON err)

prepareMsg (Ok result) = (True, result)

handleJsonMessage

    :: (J.JSON o)

    => U.Handler i o              -- ^ handler

    -> i                        -- ^ parsed input

    -> U.HandlerResult J.JSValue

handleJsonMessage handler req = do

  (close, call_result) <- U.hExec handler req

  return (close, fmap J.showJSON call_result)

-- | Takes a request as a 'String', parses it, passes it to a handler and

-- formats its response.

handleRawMessage

    :: (J.JSON o)

    => U.Handler i o              -- ^ handler

    -> String                   -- ^ raw unparsed input

    -> IO (Bool, String)

handleRawMessage handler payload =

  case U.parseCall payload >>= uncurry (U.hParse handler) of

    Bad err -> do

         let errmsg = "Failed to parse request: " ++ err

         logWarning errmsg

         return (False, buildResponse False (J.showJSON errmsg))

    Ok req -> do

        logDebug $ "Request: " ++ U.hInputLogLong handler req

        (close, call_result_json) <- handleJsonMessage handler req

        logMsg handler req call_result_json

        let (status, response) = prepareMsg call_result_json

        return (close, buildResponse status response)

-- | Reads a request, passes it to a handler and sends a response back to the

-- client.

handleClient

    :: (J.JSON o)

    => U.Handler i o

    -> Client

    -> IO Bool

handleClient handler client = do

  msg <- recvMsgExt client

  logDebug $ "Received message: " ++ show msg

  case msg of

    RecvConnClosed -> logDebug "Connection closed" >>

                      return False

    RecvError err -> logWarning ("Error during message receiving: " ++ err) >>

                     return False

    RecvOk payload -> do

      (close, outMsg) <- handleRawMessage handler payload

      sendMsg client outMsg

      return close

-- | Main client loop: runs one loop of 'handleClient', and if that

-- doesn't report a finished (closed) connection, restarts itself.

clientLoop

    :: (J.JSON o)

    => U.Handler i o

    -> Client

    -> IO ()

clientLoop handler client = do

  result <- handleClient handler client

  if result

    then clientLoop handler client

    else closeClient client

-- | Main listener loop: accepts clients, forks an I/O thread to handle

-- that client.

listener

    :: (J.JSON o)

    => U.Handler i o

    -> Server

    -> IO ()

listener handler server = do

  client <- acceptClient server

  _ <- forkIO $ clientLoop handler client

  return ()

-- | Type alias for prepMain results

type PrepResult = (Server, IORef (Result ConfigData), JQStatus)

-- | Check function for luxid.

checkMain :: CheckFn ()

checkMain _ = return $ Right ()

-- | Prepare function for luxid.

prepMain :: PrepFn () PrepResult

prepMain _ _ = do

  socket_path <- Path.defaultQuerySocket

  cleanupSocket socket_path

  s <- describeError "binding to the Luxi socket"

         Nothing (Just socket_path) $ getLuxiServer True socket_path

  cref <- newIORef (Bad "Configuration not yet loaded")

  jq <- emptyJQStatus 

  return (s, cref, jq)

-- | Main function.

main :: MainFn () PrepResult

main _ _ (server, cref, jq) = do

  initConfigReader id cref

  let creader = readIORef cref

  initJQScheduler jq

  qlockFile <- jobQueueLockFile

  lockFile qlockFile >>= exitIfBad "Failed to obtain the job-queue lock"

  qlock <- newMVar ()

  finally

    (forever $ listener (luxiHandler (qlock, jq, creader)) server)

    (closeServer server)