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{-| Some common types.
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-}
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module Ganeti.HTools.Types
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    where
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import qualified Ganeti.HTools.Container as Container
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import qualified Ganeti.HTools.Instance as Instance
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import qualified Ganeti.HTools.Node as Node
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type NodeList = Container.Container Node.Node
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type InstanceList = Container.Container Instance.Instance
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-- | The type used to hold idx-to-name mappings
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type NameList = [(Int, String)]
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-- | The type used to hold name-to-idx mappings
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type NameAssoc = [(String, Int)]
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type IdxNode = [(Int, Node.Node)]
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type IdxInstance = [(Int, Instance.Instance)]
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{-
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This is similar to the JSON library Result type - *very* similar, but
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we want to use it in multiple places, so we abstract it into a
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mini-library here
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-}
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data Result a
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    = Bad String
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    | Ok a
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    deriving (Show)
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instance Monad Result where
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    (>>=) (Bad x) _ = Bad x
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    (>>=) (Ok x) fn = fn x
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    return = Ok
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    fail = Bad
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-- | A generic class for nodes and instances
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class Element a where
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    name    :: a -> String
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    idx     :: a -> Int
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    setName :: a -> String -> a
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    setIdx  :: a -> Int -> a
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-- Let's make nodes elements of the cluster
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instance Element Node.Node where
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    name = Node.name
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    idx = Node.idx
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    setName = Node.setName
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    setIdx = Node.setIdx
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-- And instances too
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instance Element Instance.Instance where
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    name = Instance.name
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    idx = Instance.idx
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    setName = Instance.setName
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    setIdx = Instance.setIdx
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-- | Compute the name of an element in a container
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cNameOf :: (Element a) => Container.Container a -> Container.Key -> String
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cNameOf c k = name $ Container.find k c
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-- | Compute the maximum name length in an Element Container
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cMaxNamelen :: (Element a) => Container.Container a -> Int
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cMaxNamelen = maximum . map (length . name) . Container.elems