Add compatibility with rapi v1

The patch adds compatibility with RAPI v1, and this required some new
JSON functions as valFromObj doesn't behave nicely.

Some other unrelated changes were done too.

src/Rapi.hs

@@ -9,7 +9,7 @@ import Network.Curl
 import Network.Curl.Types ()
 import Network.Curl.Code
 import Data.Either ()
-import Data.Maybe ()
+import Data.Maybe
 import Control.Monad
 import Text.JSON
 import Text.Printf (printf)
@@ -47,22 +47,25 @@ listHead lst =
 loadJSArray :: String -> Either String [JSObject JSValue]
 loadJSArray s = resultToEither $ decodeStrict s
 
+fromObj :: JSON a => String -> JSObject JSValue -> Either String a
+fromObj k o =
+    case lookup k (fromJSObject o) of
+      Nothing -> Left $ printf "key '%s' not found" k
+      Just val -> resultToEither $ readJSON val
+
 getStringElement :: String -> JSObject JSValue -> Either String String
-getStringElement key o =
-    resultToEither $ valFromObj key o
+getStringElement key o = fromObj key o
 
 getIntElement :: String -> JSObject JSValue -> Either String String
 getIntElement key o =
-    let tmp = resultToEither $ ((valFromObj key o)::Result Int)
+    let tmp = (fromObj key o)::Either String Int
     in case tmp of
          Left x -> Left x
          Right x -> Right $ show x
 
 getListElement :: String -> JSObject JSValue
                -> Either String [JSValue]
-getListElement key o =
-    let tmp = resultToEither $ ((valFromObj key o)::Result [JSValue])
-    in tmp
+getListElement key o = fromObj key o
 
 readString :: JSValue -> Either String String
 readString v =
@@ -70,14 +73,20 @@ readString v =
       JSString s -> Right $ fromJSString s
       _ -> Left "Wrong JSON type"
 
-concatElems a b =
-    case a of
-      Left _ -> a
-      Right [] -> b
-      Right x ->
-          case b of
-            Left _ -> b
-            Right y ->  Right (x ++ "|" ++ y)
+concatElems :: Either String String
+            -> Either String String
+            -> Either String String
+concatElems = apply2 (\x y -> x ++ "|" ++ y)
+
+apply2 :: (a -> b -> c)
+       -> Either String a
+       -> Either String b
+       -> Either String c
+apply2 fn a b =
+    case (a, b) of
+      (Right x, Right y) -> Right $ fn x y
+      (Left x, _) -> Left x
+      (_, Left y) -> Left y
 
 getUrl :: String -> IO (Either String String)
 getUrl url = do
@@ -85,21 +94,35 @@ getUrl url = do
                                      CurlSSLVerifyHost 0]
   return (case code of
             CurlOK -> Right body
-            _ -> Left $ printf "url:%s, error: %s" url (show code))
+            _ -> Left $ printf "Curl error for '%s', error %s"
+                 url (show code))
+
+tryRapi :: String -> String -> IO (Either String String)
+tryRapi url1 url2 =
+    do
+      body1 <- getUrl url1
+      body2 <- getUrl url2
+      return (case body1 of
+                Left _ -> body2
+                Right _ -> body1)
 
 getInstances :: String -> IO (Either String String)
 getInstances master =
-    let url = printf "https://%s:5080/2/instances?bulk=1" master
+    let
+        url2 = printf "https://%s:5080/2/instances?bulk=1" master
+        url1 = printf "http://%s:5080/instances?bulk=1" master
     in do
-      body <- getUrl  url
+      body <- tryRapi url1 url2
       let inst = body `combine` loadJSArray `combine` (parseList parseInstance)
       return inst
 
 getNodes :: String -> IO (Either String String)
 getNodes master =
-    let url = printf "https://%s:5080/2/nodes?bulk=1" master
+    let
+        url2 = printf "https://%s:5080/2/nodes?bulk=1" master
+        url1 = printf "http://%s:5080/nodes?bulk=1" master
     in do
-      body <- getUrl  url
+      body <- tryRapi url1 url2
       let inst = body `combine` loadJSArray `combine` (parseList parseNode)
       return inst
 
@@ -114,17 +137,19 @@ parseInstance :: JSObject JSValue -> Either String String
 parseInstance a =
     let name = getStringElement "name" a
         disk = case getIntElement "disk_usage" a of
-                 Left _ -> getIntElement "sda_size" a
+                 Left _ -> apply2 (\x y -> show $ ((read x)::Int) + ((read y)::Int))
+                           (getIntElement "sda_size" a)
+                           (getIntElement "sdb_size" a)
                  Right x -> Right x
-        bep = (resultToEither $ valFromObj "beparams" a)
+        bep = fromObj "beparams" a
         pnode = getStringElement "pnode" a
         snode = (listHead $ getListElement "snodes" a) `combine` readString
+        mem = case bep of
+                Left _ -> getIntElement "admin_ram" a
+                Right _ -> bep
     in
-      case bep of
-        Left x -> Left x
-        Right x -> let mem = getIntElement "memory" x
-                   in concatElems name $ concatElems mem $
-                      concatElems disk $ concatElems pnode snode
+      concatElems name $ concatElems mem $
+                  concatElems disk $ concatElems pnode snode
 
 parseNode :: JSObject JSValue -> Either String String
 parseNode a =