Implement hail allocate (for 2-node requests)

[ganeti-local] / Ganeti / HTools / Utils.hs

diff --git a/Ganeti/HTools/Utils.hs b/Ganeti/HTools/Utils.hs
index 737b94a..89cf3cb 100644 (file)
--- a/Ganeti/HTools/Utils.hs
+++ b/Ganeti/HTools/Utils.hs
@@ -1,16 +1,28 @@
 {-| Utility functions -}
 
-module Ganeti.HTools.Utils where
+module Ganeti.HTools.Utils
+    (
+      debug
+    , sepSplit
+    , varianceCoeff
+    , readData
+    , commaJoin
+    , readEitherString
+    , loadJSArray
+    , fromObj
+    , asJSObject
+    , asObjectList
+    , fromJResult
+    ) where
 
-import Data.Either
 import Data.List
-import qualified Data.Version
-import Monad
+import Control.Monad
 import System
 import System.IO
-import System.Info
-import Text.Printf
-import qualified Ganeti.HTools.Version as Version
+import qualified Text.JSON as J
+import Text.Printf (printf)
+
+import Ganeti.HTools.Types
 
 import Debug.Trace
 
@@ -18,18 +30,10 @@ import Debug.Trace
 debug :: Show a => a -> a
 debug x = trace (show x) x
 
--- | Check if the given argument is Left something
-isLeft :: Either a b -> Bool
-isLeft val =
-    case val of
-      Left _ -> True
-      _ -> False
-
-fromLeft :: Either a b -> a
-fromLeft = either (\x -> x) (\_ -> undefined)
 
-fromRight :: Either a b -> b
-fromRight = either (\_ -> undefined) id
+fromJResult :: Monad m => J.Result a -> m a
+fromJResult (J.Error x) = fail x
+fromJResult (J.Ok x) = return x
 
 -- | Comma-join a string list.
 commaJoin :: [String] -> String
@@ -49,10 +53,6 @@ sepSplit sep s
 commaSplit :: String -> [String]
 commaSplit = sepSplit ','
 
--- | Swap a list of @(a, b)@ into @(b, a)@
-swapPairs :: [(a, b)] -> [(b, a)]
-swapPairs = map (\ (a, b) -> (b, a))
-
 -- Simple and slow statistical functions, please replace with better versions
 
 -- | Mean value of a list.
@@ -68,25 +68,37 @@ stdDev lst =
         bv = sqrt (av / (fromIntegral $ length lst))
     in bv
 
-
 -- | Coefficient of variation.
 varianceCoeff :: Floating a => [a] -> a
 varianceCoeff lst = (stdDev lst) / (fromIntegral $ length lst)
 
--- | Get a Right result or print the error and exit
-readData :: (String -> IO (Either String String)) -> String -> IO String
-readData fn host = do
-  nd <- fn host
-  when (isLeft nd) $
-       do
-         putStrLn $ fromLeft nd
+-- | Get an Ok result or print the error and exit
+readData :: Result a -> IO a
+readData nd =
+    (case nd of
+       Bad x -> do
+         putStrLn x
          exitWith $ ExitFailure 1
-  return $ fromRight nd
-
-showVersion :: String -- ^ The program name
-            -> String -- ^ The formatted version and other information data
-showVersion name =
-    printf "%s %s\ncompiled with %s %s\nrunning on %s %s\n"
-           name Version.version
-           compilerName (Data.Version.showVersion compilerVersion)
-           os arch
+       Ok x -> return x)
+
+readEitherString :: (Monad m) => J.JSValue -> m String
+readEitherString v =
+    case v of
+      J.JSString s -> return $ J.fromJSString s
+      _ -> fail "Wrong JSON type"
+
+loadJSArray :: (Monad m) => String -> m [J.JSObject J.JSValue]
+loadJSArray s = fromJResult $ J.decodeStrict s
+
+fromObj :: (J.JSON a, Monad m) => String -> J.JSObject J.JSValue -> m a
+fromObj k o =
+    case lookup k (J.fromJSObject o) of
+      Nothing -> fail $ printf "key '%s' not found in %s" k (show o)
+      Just val -> fromJResult $ J.readJSON val
+
+asJSObject :: (Monad m) => J.JSValue -> m (J.JSObject J.JSValue)
+asJSObject (J.JSObject a) = return a
+asJSObject _ = fail "not an object"
+
+asObjectList :: (Monad m) => [J.JSValue] -> m [J.JSObject J.JSValue]
+asObjectList = sequence . map asJSObject