On Fri, Sep 27, 2013 at 12:02 PM, Spyros Trigazis <[email protected]>wrote:
> Implement readJSON functions for DCCategory, DCVersion and > DCKind in Data Collectors's Types to be parsable from a JSON > formatted file. Also, implement a utility function to > capitalize the first character of a string. > > Signed-off-by: Spyros Trigazis <[email protected]> > --- > src/Ganeti/DataCollectors/Types.hs | 33 > ++++++++++++++++++++++++++++----- > 1 file changed, 28 insertions(+), 5 deletions(-) > > diff --git a/src/Ganeti/DataCollectors/Types.hs > b/src/Ganeti/DataCollectors/Types.hs > index ec55cd5..591b857 100644 > --- a/src/Ganeti/DataCollectors/Types.hs > +++ b/src/Ganeti/DataCollectors/Types.hs > @@ -41,8 +41,10 @@ module Ganeti.DataCollectors.Types > ) where > > import Data.Char > +import Data.Ratio > import qualified Data.Map as Map > import qualified Data.Sequence as Seq > +import qualified Data.List as L > import Text.JSON > > import Ganeti.Constants as C > @@ -51,17 +53,27 @@ import Ganeti.Utils (getCurrentTime) > > -- | The possible classes a data collector can belong to. > data DCCategory = DCInstance | DCStorage | DCDaemon | DCHypervisor > - deriving (Show, Eq) > + deriving (Show, Eq, Read) > > -- | Gets the category name and returns it as a string. > getCategoryName :: DCCategory -> String > getCategoryName dcc = map toLower . drop 2 . show $ dcc > > +categoryNames :: [(DCCategory, String)] > I like this way of avoiding the need to have a manual list of all the names to implement readJSON. But why not using a Map instead of a list? So you'll have faster search times. +categoryNames = > + let l = [DCInstance, DCStorage, DCDaemon, DCHypervisor] > + in zip l (map getCategoryName l) > + > -- | The JSON instance for DCCategory. > instance JSON DCCategory where > showJSON = showJSON . getCategoryName > - readJSON = > - error "JSON read instance not implemented for type DCCategory" > + readJSON (JSString s) = > + let s' = fromJSString s > + in case L.find ((== s') . snd) categoryNames of > + Just (category, _) -> Ok category > + Nothing -> fail $ "Invalid category name " ++ s' ++ " for type\ > + \ DCCategory" > + readJSON v = fail $ "Invalid JSON value " ++ show v ++ " for type > DCCategory" > > -- | The possible status codes of a data collector. > data DCStatusCode = DCSCOk -- ^ Everything is OK > @@ -93,7 +105,15 @@ data DCKind = DCKPerf -- ^ Performance reporting > collector > instance JSON DCKind where > showJSON DCKPerf = showJSON (0 :: Int) > showJSON DCKStatus = showJSON (1 :: Int) > - readJSON = error "JSON read instance not implemented for type DCKind" > + readJSON (JSRational _ x) = > + if denominator x /= 1 > + then fail $ "Invalid JSON value " ++ show x ++ " for type DCKind" > + else > + let x' = (fromIntegral . numerator $ x) :: Int > + in if x' == 0 then Ok DCKPerf > + else if x' == 1 then Ok DCKStatus > + else fail $ "Invalid JSON value " ++ show x' ++ " for type > DCKind" > + readJSON v = fail $ "Invalid JSON value " ++ show v ++ " for type > DCKind" > > -- | Type representing the version number of a data collector. > data DCVersion = DCVerBuiltin | DCVersion String deriving (Show, Eq) > @@ -102,7 +122,10 @@ data DCVersion = DCVerBuiltin | DCVersion String > deriving (Show, Eq) > instance JSON DCVersion where > showJSON DCVerBuiltin = showJSON C.builtinDataCollectorVersion > showJSON (DCVersion v) = showJSON v > - readJSON = error "JSON read instance not implemented for type DCVersion" > + readJSON (JSString s) = > + if fromJSString s == C.builtinDataCollectorVersion > + then Ok DCVerBuiltin else Ok . DCVersion $ fromJSString s > + readJSON v = fail $ "Invalid JSON value " ++ show v ++ " for type > DCVersion" > > -- | Type for the value field of the above map. > data CollectorData = CPULoadData (Seq.Seq (Integer, [Int])) > -- > 1.7.10.4 > > Rest LGTM. Thanks, Michele -- Google Germany GmbH Dienerstr. 12 80331 München Registergericht und -nummer: Hamburg, HRB 86891 Sitz der Gesellschaft: Hamburg Geschäftsführer: Graham Law, Christine Elizabeth Flores
