src/Gargantext/Utils/Servant.hs

   1 module Gargantext.Utils.Servant where
   2
   3 import qualified Data.ByteString.Lazy.Char8 as BSC
   4 import Data.Csv (defaultEncodeOptions, encodeByNameWith, encodeDefaultOrderedByName, header, namedRecord, (.=), DefaultOrdered, EncodeOptions(..), NamedRecord, Quoting(QuoteNone), ToNamedRecord)
   5 import qualified Data.Map as Map
   6 import qualified Data.Text as T
   7 import Gargantext.API.Ngrams.Types (mSetToList, NgramsRepoElement(..), NgramsTableMap, NgramsTerm(..), unNgramsTerm)
   8 import Gargantext.Core.Types.Main (ListType(..))
   9 import Network.HTTP.Media ((//), (/:))
  10 import qualified Prelude
  11 import Protolude
  12 import Protolude.Partial (read)
  13 import Servant
  14
  15 data CSV = CSV
  16
  17 instance Accept CSV where
  18   contentType _ = "text" // "csv" /: ("charset", "utf-8")
  19
  20 instance (DefaultOrdered a, ToNamedRecord a) => MimeRender CSV [a] where
  21   mimeRender _ val = encodeDefaultOrderedByName val
  22
  23 -- CSV:
  24 -- header: status\tlabel\tforms
  25 -- item: map\taccountability\taccounting|&|accoutns|&|account
  26 instance MimeRender CSV NgramsTableMap where
  27   -- mimeRender _ _val = encode ([] :: [(Text, Text)])
  28   mimeRender _ val = encodeByNameWith encOptions (header ["status", "label", "forms"]) $ fn <$> Map.toList val
  29     where
  30       encOptions = defaultEncodeOptions { encDelimiter = fromIntegral (ord '\t')
  31                                         , encQuoting = QuoteNone }
  32       fn :: (NgramsTerm, NgramsRepoElement) -> NamedRecord
  33       fn (NgramsTerm term, NgramsRepoElement { _nre_list, _nre_children }) =
  34         namedRecord [ "status" .= toText _nre_list
  35                     , "label" .= term
  36                     , "forms" .= (T.intercalate "|&|" $ unNgramsTerm <$> mSetToList _nre_children)]
  37       toText :: ListType -> Text
  38       toText CandidateTerm = "candidate"
  39       toText MapTerm = "map"
  40       toText StopTerm = "stop"
  41
  42 instance Read a => MimeUnrender CSV a where
  43    mimeUnrender _ bs = case BSC.take len bs of
  44      "text/csv" -> return . read . BSC.unpack $ BSC.drop len bs
  45      _ -> Left "didn't start with the magic incantation"
  46      where
  47        len :: Int64
  48        len = fromIntegral $ length ("text/csv" :: Prelude.String)
  49
  50 --instance ToNamedRecord a => MimeRender CSV [a] where
  51 --  mimeRender _ val = encode val