Add LV data collector

This commit adds the LV data collector.

Also, the lvCommand function was not providing the correct value as expected by
the readProcess function, so it was fixed.

Signed-off-by: Michele Tartara <mtartara@google.com>
Reviewed-by: Helga Velroyen <helgav@google.com>

diff --git a/Makefile.am b/Makefile.am
index 1a85084..9c3c5f7 100644 (file)
--- a/Makefile.am
+++ b/Makefile.am
@@ -553,6 +553,7 @@ HS_LIB_SRCS = \
        src/Ganeti/DataCollectors/Drbd.hs \
        src/Ganeti/DataCollectors/InstStatus.hs \
        src/Ganeti/DataCollectors/InstStatusTypes.hs \
+       src/Ganeti/DataCollectors/Lv.hs \
        src/Ganeti/DataCollectors/Program.hs \
        src/Ganeti/DataCollectors/Types.hs \
        src/Ganeti/Errors.hs \

diff --git a/src/Ganeti/DataCollectors/Lv.hs b/src/Ganeti/DataCollectors/Lv.hs
new file mode 100644 (file)
index 0000000..8c34c34
--- /dev/null
+++ b/src/Ganeti/DataCollectors/Lv.hs
@@ -0,0 +1,129 @@
+{-| Logical Volumes data collector.
+
+-}
+
+{-
+
+Copyright (C) 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.DataCollectors.Lv
+  ( main
+  , options
+  , arguments
+  , dcName
+  , dcVersion
+  , dcFormatVersion
+  , dcCategory
+  , dcKind
+  , dcReport
+  ) where
+
+
+import qualified Control.Exception as E
+import Control.Monad
+import Data.Attoparsec.Text.Lazy as A
+import Data.Text.Lazy (pack, unpack)
+import System.Process
+import qualified Text.JSON as J
+
+import qualified Ganeti.BasicTypes as BT
+import Ganeti.Common
+import Ganeti.DataCollectors.CLI
+import Ganeti.DataCollectors.Types
+import Ganeti.Storage.Lvm.LVParser
+import Ganeti.Utils
+
+
+-- | The default setting for the maximum amount of not parsed character to
+-- print in case of error.
+-- It is set to use most of the screen estate on a standard 80x25 terminal.
+-- TODO: add the possibility to set this with a command line parameter.
+defaultCharNum :: Int
+defaultCharNum = 80*20
+
+-- | The name of this data collector.
+dcName :: String
+dcName = "lv"
+
+-- | The version of this data collector.
+dcVersion :: DCVersion
+dcVersion = DCVerBuiltin
+
+-- | The version number for the data format of this data collector.
+dcFormatVersion :: Int
+dcFormatVersion = 1
+
+-- | The category of this data collector.
+dcCategory :: Maybe DCCategory
+dcCategory = Just DCStorage
+
+-- | The kind of this data collector.
+dcKind :: DCKind
+dcKind = DCKPerf
+
+-- | The data exported by the data collector, taken from the default location.
+dcReport :: IO DCReport
+dcReport = buildDCReport Nothing
+
+-- * Command line options
+
+options :: IO [OptType]
+options =
+  return
+    [ oInputFile
+    ]
+
+-- | The list of arguments supported by the program.
+arguments :: [ArgCompletion]
+arguments = [ArgCompletion OptComplFile 0 (Just 0)]
+
+-- | This function computes the JSON representation of the LV status
+buildJsonReport :: Maybe FilePath -> IO J.JSValue
+buildJsonReport inputFile = do
+  let (cmd:params) = lvCommand
+      fromLvs =
+        ((E.try $ readProcess cmd params "") :: IO (Either IOError String)) >>=
+          exitIfBad "running command" . either (BT.Bad . show) BT.Ok
+  contents <-
+    maybe fromLvs (\fn -> ((E.try $ readFile fn) :: IO (Either IOError String))
+      >>= exitIfBad "reading from file" . either (BT.Bad . show) BT.Ok)
+      inputFile
+  lvInfo <-
+    case A.parse lvParser $ pack contents of
+      A.Fail unparsedText contexts errorMessage -> exitErr $
+        show (Prelude.take defaultCharNum $ unpack unparsedText) ++ "\n"
+          ++ show contexts ++ "\n" ++ errorMessage
+      A.Done _ lvinfoD -> return lvinfoD
+  return $ J.showJSON lvInfo
+
+-- | This function computes the DCReport for the logical volumes.
+buildDCReport :: Maybe FilePath -> IO DCReport
+buildDCReport inputFile =
+  buildJsonReport inputFile >>=
+    buildReport dcName dcVersion dcFormatVersion dcCategory dcKind
+
+-- | Main function.
+main :: Options -> [String] -> IO ()
+main opts args = do
+  unless (null args) . exitErr $ "This program takes exactly zero" ++
+                                 " arguments, got '" ++ unwords args ++ "'"
+  report <- buildDCReport $ optInputFile opts
+
+  putStrLn $ J.encode report

diff --git a/src/Ganeti/DataCollectors/Program.hs b/src/Ganeti/DataCollectors/Program.hs
index 6d95dd8..7005535 100644 (file)
--- a/src/Ganeti/DataCollectors/Program.hs
+++ b/src/Ganeti/DataCollectors/Program.hs
@@ -31,6 +31,7 @@ import Ganeti.DataCollectors.CLI (Options)
 import qualified Ganeti.DataCollectors.Diskstats as Diskstats
 import qualified Ganeti.DataCollectors.Drbd as Drbd
 import qualified Ganeti.DataCollectors.InstStatus as InstStatus
+import qualified Ganeti.DataCollectors.Lv as Lv
 
 -- | Supported binaries.
 personalities :: PersonalityList Options
@@ -45,4 +46,6 @@ personalities = [ (Drbd.dcName, (Drbd.main, Drbd.options, Drbd.arguments,
                                       Diskstats.arguments,
                                       "gathers and displays the disk usage\
                                       \ statistics in JSON format"))
+                , (Lv.dcName, (Lv.main, Lv.options, Lv.arguments, "gathers and\
+                               \ displays info about logical volumes"))
                 ]

diff --git a/src/Ganeti/Storage/Lvm/LVParser.hs b/src/Ganeti/Storage/Lvm/LVParser.hs
index c260c84..b51aa86 100644 (file)
--- a/src/Ganeti/Storage/Lvm/LVParser.hs
+++ b/src/Ganeti/Storage/Lvm/LVParser.hs
@@ -74,9 +74,9 @@ lvCommand :: [String]
 lvCommand =
   [ "lvs"
   , "--noheadings"
-  , "--units B"
-  , "-- separator ;"
-  , "-o lv_uuid,lv_name,lv_attr,lv_major,lv_minor,lv_kernel_major\
+  , "--units", "B"
+  , "--separator", ";"
+  , "-o", "lv_uuid,lv_name,lv_attr,lv_major,lv_minor,lv_kernel_major\
     \,lv_kernel_minor,lv_size,seg_count,lv_tags,modules,vg_uuid,vg_name,segtype\
     \,seg_start,seg_start_pe,seg_size,seg_tags,seg_pe_ranges,devices"
   ]