Synnefo » snf-ganeti

{-| Parsing data from text-files.

This module holds the code for loading the cluster state from text

files, as produced by @gnt-node@ and @gnt-instance@ @list@ command.

-}

{-

Copyright (C) 2009, 2010, 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.

-}

module Ganeti.HTools.Text

    (

      loadData

    , parseData

    , loadInst

    , loadNode

    , serializeInstances

    , serializeNode

    , serializeNodes

    , serializeCluster

    ) where

import Control.Monad

import Data.List

import Text.Printf (printf)

import Ganeti.HTools.Utils

import Ganeti.HTools.Loader

import Ganeti.HTools.Types

import qualified Ganeti.HTools.Container as Container

import qualified Ganeti.HTools.Group as Group

import qualified Ganeti.HTools.Node as Node

import qualified Ganeti.HTools.Instance as Instance

-- * Serialisation functions

-- | Serialize a single group.

serializeGroup :: Group.Group -> String

serializeGroup grp =

    printf "%s|%s|%s" (Group.name grp) (Group.uuid grp)

               (apolToString (Group.allocPolicy grp))

-- | Generate group file data from a group list.

serializeGroups :: Group.List -> String

serializeGroups = unlines . map serializeGroup . Container.elems

-- | Serialize a single node.

serializeNode :: Group.List -- ^ The list of groups (needed for group uuid)

              -> Node.Node  -- ^ The node to be serialised

              -> String

serializeNode gl node =

    printf "%s|%.0f|%d|%d|%.0f|%d|%.0f|%c|%s" (Node.name node)

               (Node.tMem node) (Node.nMem node) (Node.fMem node)

               (Node.tDsk node) (Node.fDsk node) (Node.tCpu node)

               (if Node.offline node then 'Y' else 'N')

               (Group.uuid grp)

    where grp = Container.find (Node.group node) gl

-- | Generate node file data from node objects.

serializeNodes :: Group.List -> Node.List -> String

serializeNodes gl = unlines . map (serializeNode gl) . Container.elems

-- | Serialize a single instance.

serializeInstance :: Node.List         -- ^ The node list (needed for

                                       -- node names)

                  -> Instance.Instance -- ^ The instance to be serialised

                  -> String

serializeInstance nl inst =

    let

        iname = Instance.name inst

        pnode = Container.nameOf nl (Instance.pNode inst)

        sidx = Instance.sNode inst

        snode = (if sidx == Node.noSecondary

                    then ""

                    else Container.nameOf nl sidx)

    in

      printf "%s|%d|%d|%d|%s|%s|%s|%s|%s|%s"

             iname (Instance.mem inst) (Instance.dsk inst)

             (Instance.vcpus inst) (Instance.runSt inst)

             (if Instance.autoBalance inst then "Y" else "N")

             pnode snode (dtToString (Instance.diskTemplate inst))

             (intercalate "," (Instance.tags inst))

-- | Generate instance file data from instance objects.

serializeInstances :: Node.List -> Instance.List -> String

serializeInstances nl =

    unlines . map (serializeInstance nl) . Container.elems

-- | Generate complete cluster data from node and instance lists.

serializeCluster :: ClusterData -> String

serializeCluster (ClusterData gl nl il ctags) =

  let gdata = serializeGroups gl

      ndata = serializeNodes gl nl

      idata = serializeInstances nl il

  -- note: not using 'unlines' as that adds too many newlines

  in intercalate "\n" [gdata, ndata, idata, unlines ctags]

-- * Parsing functions

-- | Load a group from a field list.

loadGroup :: (Monad m) => [String]

          -> m (String, Group.Group) -- ^ The result, a tuple of group

                                     -- UUID and group object

loadGroup [name, gid, apol] = do

  xapol <- apolFromString apol

  return (gid, Group.create name gid xapol)

loadGroup s = fail $ "Invalid/incomplete group data: '" ++ show s ++ "'"

-- | Load a node from a field list.

loadNode :: (Monad m) =>

            NameAssoc             -- ^ Association list with current groups

         -> [String]              -- ^ Input data as a list of fields

         -> m (String, Node.Node) -- ^ The result, a tuple o node name

                                  -- and node object

loadNode ktg [name, tm, nm, fm, td, fd, tc, fo, gu] = do

  gdx <- lookupGroup ktg name gu

  new_node <-

      if any (== "?") [tm,nm,fm,td,fd,tc] || fo == "Y" then

          return $ Node.create name 0 0 0 0 0 0 True gdx

      else do

        vtm <- tryRead name tm

        vnm <- tryRead name nm

        vfm <- tryRead name fm

        vtd <- tryRead name td

        vfd <- tryRead name fd

        vtc <- tryRead name tc

        return $ Node.create name vtm vnm vfm vtd vfd vtc False gdx

  return (name, new_node)

loadNode _ s = fail $ "Invalid/incomplete node data: '" ++ show s ++ "'"

-- | Load an instance from a field list.

loadInst :: NameAssoc -- ^ Association list with the current nodes

         -> [String]  -- ^ Input data as a list of fields

         -> Result (String, Instance.Instance) -- ^ A tuple of

                                               -- instance name and

                                               -- the instance object

loadInst ktn [ name, mem, dsk, vcpus, status, auto_bal, pnode, snode

             , dt, tags ] = do

  pidx <- lookupNode ktn name pnode

  sidx <- (if null snode then return Node.noSecondary

           else lookupNode ktn name snode)

  vmem <- tryRead name mem

  vdsk <- tryRead name dsk

  vvcpus <- tryRead name vcpus

  auto_balance <- case auto_bal of

                    "Y" -> return True

                    "N" -> return False

                    _ -> fail $ "Invalid auto_balance value '" ++ auto_bal ++

                         "' for instance " ++ name

  disk_template <- annotateResult ("Instance " ++ name) (dtFromString dt)

  when (sidx == pidx) $ fail $ "Instance " ++ name ++

           " has same primary and secondary node - " ++ pnode

  let vtags = sepSplit ',' tags

      newinst = Instance.create name vmem vdsk vvcpus status vtags

                auto_balance pidx sidx disk_template

  return (name, newinst)

loadInst _ s = fail $ "Invalid/incomplete instance data: '" ++ show s ++ "'"

-- | Convert newline and delimiter-separated text.

--

-- This function converts a text in tabular format as generated by

-- @gnt-instance list@ and @gnt-node list@ to a list of objects using

-- a supplied conversion function.

loadTabular :: (Monad m, Element a) =>

               [String] -- ^ Input data, as a list of lines

            -> ([String] -> m (String, a)) -- ^ Conversion function

            -> m ( NameAssoc

                 , Container.Container a ) -- ^ A tuple of an

                                           -- association list (name

                                           -- to object) and a set as

                                           -- used in

                                           -- "Ganeti.HTools.Container"

loadTabular lines_data convert_fn = do

  let rows = map (sepSplit '|') lines_data

  kerows <- mapM convert_fn rows

  return $ assignIndices kerows

-- | Load the cluser data from disk.

--

-- This is an alias to 'readFile' just for consistency with the other

-- modules.

readData :: String    -- ^ Path to the text file

         -> IO String -- ^ Contents of the file

readData = readFile

-- | Builds the cluster data from text input.

parseData :: String -- ^ Text data

          -> Result ClusterData

parseData fdata = do

  let flines = lines fdata

  (glines, nlines, ilines, ctags) <-

      case sepSplit "" flines of

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

        xs -> Bad $ printf "Invalid format of the input file: %d sections\

                           \ instead of 4" (length xs)

  {- group file: name uuid -}

  (ktg, gl) <- loadTabular glines loadGroup

  {- node file: name t_mem n_mem f_mem t_disk f_disk -}

  (ktn, nl) <- loadTabular nlines (loadNode ktg)

  {- instance file: name mem disk status pnode snode -}

  (_, il) <- loadTabular ilines (loadInst ktn)

  {- the tags are simply line-based, no processing needed -}

  return (ClusterData gl nl il ctags)

-- | Top level function for data loading.

loadData :: String -- ^ Path to the text file

         -> IO (Result ClusterData)

loadData = fmap parseData . readData