@@ -2,6 +2,7 @@
22{-# LANGUAGE FlexibleInstances, TypeSynonymInstances #-}
33{-# LANGUAGE PatternGuards, ScopedTypeVariables #-}
44{-# LANGUAGE RecordWildCards #-}
5+{-# LANGUAGE PolyKinds #-}
56
67{- |
78Module: Database.PostgreSQL.Simple.FromField
@@ -106,26 +107,27 @@ module Database.PostgreSQL.Simple.FromField
106107 , PQ.Oid(..)
107108 , PQ.Format(..)
108109 , pgArrayFieldParser
110+ , attoFieldParser
109111
110112 , optionalField
111113 , fromJSONField
114+ , fromFieldJSONByteString
112115 ) where
113116
114117#include "MachDeps.h"
115118
116−import Control.Applicative ( (<|>), (<$>), pure, (*>), (<*) )
119+import Control.Applicative ( Const(Const), (<|>), (<$>), pure, (*>), (<*) )
117120import Control.Concurrent.MVar (MVar, newMVar)
118−import Control.Exception (Exception)
121+import Control.Exception (Exception (toException, fromException))
119122import qualified Data.Aeson as JSON
120−import qualified Data.Aeson.Internal as JSON
121−import qualified Data.Aeson.Parser as JSON (value')
122123import Data.Attoparsec.ByteString.Char8 hiding (Result)
123124import Data.ByteString (ByteString)
124125import qualified Data.ByteString.Char8 as B
126+import Data.Functor.Identity (Identity(Identity))
125127import Data.Int (Int16, Int32, Int64)
126128import Data.IORef (IORef, newIORef)
127129import Data.Ratio (Ratio)
128−import Data.Time ( UTCTime, ZonedTime, LocalTime, Day, TimeOfDay )
130+import Data.Time.Compat ( UTCTime, ZonedTime, LocalTime, Day, TimeOfDay, CalendarDiffTime )
129131import Data.Typeable (Typeable, typeOf)
130132import Data.Vector (Vector)
131133import Data.Vector.Mutable (IOVector)
@@ -152,6 +154,8 @@ import qualified Data.UUID.Types as UUID
152154import Data.Scientific (Scientific)
153155import GHC.Real (infinity, notANumber)
154156
157+import qualified Data.Aeson.Types as JSON
158+
155159-- | Exception thrown if conversion from a SQL value to a Haskell
156160-- value fails.
157161data ResultError = Incompatible { errSQLType :: String
@@ -178,7 +182,9 @@ data ResultError = Incompatible { errSQLType :: String
178182 -- between metadata and actual data in a row).
179183 deriving (Eq, Show, Typeable)
180184
181−instance Exception ResultError
185+instance Exception ResultError where
186+ toException = postgresqlExceptionToException
187+ fromException = postgresqlExceptionFromException
182188
183189left :: Exception a => a -> Conversion b
184190left = conversionError
@@ -244,9 +250,11 @@ tableOid Field{..} = toMaybeOid (unsafeDupablePerformIO (PQ.ftable result column
244250 then Nothing
245251 else Just x
246252
247−-- | If the column has a table associated with it, this returns the number
248−-- off the associated table column. Numbering starts from 0. Analogous
249−-- to libpq's @PQftablecol@.
253+-- | If the column has a table associated with it, this returns the
254+-- number of the associated table column. Table columns have
255+-- nonzero numbers. Zero is returned if the specified column is not
256+-- a simple reference to a table column, or when using pre-3.0
257+-- protocol. Analogous to libpq's @PQftablecol@.
250258
251259tableColumn :: Field -> Int
252260tableColumn Field{..} = fromCol (unsafeDupablePerformIO (PQ.ftablecol result column))
@@ -265,6 +273,12 @@ instance FromField () where
265273 | typeOid f /= TI.voidOid = returnError Incompatible f ""
266274 | otherwise = pure ()
267275
276+instance (FromField a) => FromField (Const a b) where
277+ fromField f bs = Const <$> fromField f bs
278+
279+instance (FromField a) => FromField (Identity a) where
280+ fromField f bs = Identity <$> fromField f bs
281+
268282-- | For dealing with null values. Compatible with any postgresql type
269283-- compatible with type @a@. Note that the type is not checked if
270284-- the value is null, although it is inadvisable to rely on this
@@ -311,11 +325,11 @@ instance FromField Char where
311325
312326-- | int2
313327instance FromField Int16 where
314− fromField = atto ok16 $ signed decimal
328+ fromField = attoFieldParser ok16 $ signed decimal
315329
316330-- | int2, int4
317331instance FromField Int32 where
318− fromField = atto ok32 $ signed decimal
332+ fromField = attoFieldParser ok32 $ signed decimal
319333
320334#if WORD_SIZE_IN_BITS < 64
321335-- | int2, int4, and if compiled as 64-bit code, int8 as well.
@@ -325,36 +339,36 @@ instance FromField Int32 where
325339-- This library was compiled as 64-bit code.
326340#endif
327341instance FromField Int where
328− fromField = atto okInt $ signed decimal
342+ fromField = attoFieldParser okInt $ signed decimal
329343
330344-- | int2, int4, int8
331345instance FromField Int64 where
332− fromField = atto ok64 $ signed decimal
346+ fromField = attoFieldParser ok64 $ signed decimal
333347
334348-- | int2, int4, int8
335349instance FromField Integer where
336− fromField = atto ok64 $ signed decimal
350+ fromField = attoFieldParser ok64 $ signed decimal
337351
338352-- | int2, float4 (Uses attoparsec's 'double' routine, for
339353-- better accuracy convert to 'Scientific' or 'Rational' first)
340354instance FromField Float where
341− fromField = atto ok (realToFrac <$> pg_double)
355+ fromField = attoFieldParser ok (realToFrac <$> pg_double)
342356 where ok = eq TI.float4Oid \/ eq TI.int2Oid
343357
344358-- | int2, int4, float4, float8 (Uses attoparsec's 'double' routine, for
345359-- better accuracy convert to 'Scientific' or 'Rational' first)
346360instance FromField Double where
347− fromField = atto ok pg_double
361+ fromField = attoFieldParser ok pg_double
348362 where ok = eq TI.float4Oid \/ eq TI.float8Oid \/ eq TI.int2Oid \/ eq TI.int4Oid
349363
350364-- | int2, int4, int8, float4, float8, numeric
351365instance FromField (Ratio Integer) where
352− fromField = atto ok pg_rational
366+ fromField = attoFieldParser ok pg_rational
353367 where ok = eq TI.float4Oid \/ eq TI.float8Oid \/ eq TI.int2Oid \/ eq TI.int4Oid \/ eq TI.int8Oid \/ eq TI.numericOid
354368
355369-- | int2, int4, int8, float4, float8, numeric
356370instance FromField Scientific where
357− fromField = atto ok rational
371+ fromField = attoFieldParser ok rational
358372 where ok = eq TI.float4Oid \/ eq TI.float8Oid \/ eq TI.int2Oid \/ eq TI.int4Oid \/ eq TI.int8Oid \/ eq TI.numericOid
359373
360374unBinary :: Binary t -> t
@@ -382,7 +396,7 @@ instance FromField SB.ByteString where
382396
383397-- | oid
384398instance FromField PQ.Oid where
385− fromField f dat = PQ.Oid <$> atto (== TI.oidOid) decimal f dat
399+ fromField f dat = PQ.Oid <$> attoFieldParser (== TI.oidOid) decimal f dat
386400
387401-- | bytea, name, text, \"char\", bpchar, varchar, unknown
388402instance FromField LB.ByteString where
@@ -475,6 +489,15 @@ instance FromField LocalTimestamp where
475489instance FromField Date where
476490 fromField = ff TI.dateOid "Date" parseDate
477491
492+-- | interval. Requires you to configure intervalstyle as @iso_8601@.
493+--
494+-- You can configure intervalstyle on every connection with a @SET@ command,
495+-- but for better performance you may want to configure it permanently in the
496+-- file found with @SHOW config_file;@ .
497+--
498+instance FromField CalendarDiffTime where
499+ fromField = ff TI.intervalOid "CalendarDiffTime" parseCalendarDiffTime
500+
478501ff :: PQ.Oid -> String -> (B8.ByteString -> Either String a)
479502 -> Field -> Maybe B8.ByteString -> Conversion a
480503ff compatOid hsType parseBS f mstr =
@@ -553,11 +576,13 @@ instance FromField UUID where
553576-- | json, jsonb
554577instance FromField JSON.Value where
555578 fromField f mbs = parseBS =<< fromFieldJSONByteString f mbs
556− where parseBS bs = case parseOnly (JSON.value' <* endOfInput) bs of
579+ where parseBS bs = case JSON.eitherDecodeStrict' bs of
557580 Left err -> returnError ConversionFailed f err
558581 Right val -> pure val
559582
560583-- | Return the JSON ByteString directly
584+--
585+-- @since 0.6.3
561586fromFieldJSONByteString :: Field -> Maybe ByteString -> Conversion ByteString
562587fromFieldJSONByteString f mbs =
563588 if typeOid f /= TI.jsonOid && typeOid f /= TI.jsonbOid
@@ -659,10 +684,22 @@ returnError mkErr f msg = do
659684 (show (typeOf (undefined :: a)))
660685 msg
661686
662−atto :: forall a. (Typeable a)
663− => Compat -> Parser a -> Field -> Maybe ByteString
664− -> Conversion a
665−atto types p0 f dat = doFromField f types (go p0) dat
687+-- | Construct a field parser from an attoparsec parser. An 'Incompatible' error is thrown if the
688+-- PostgreSQL oid does not match the specified predicate.
689+--
690+-- @
691+-- instance FromField Int16 where
692+-- fromField = attoFieldParser ok16 (signed decimal)
693+-- @
694+--
695+-- @since 0.6.3
696+attoFieldParser :: forall a. (Typeable a)
697+ => (PQ.Oid -> Bool)
698+ -- ^ Predicate for whether the postgresql type oid is compatible with this parser
699+ -> Parser a
700+ -- ^ An attoparsec parser.
701+ -> FieldParser a
702+attoFieldParser types p0 f dat = doFromField f types (go p0) dat
666703 where
667704 go :: Parser a -> ByteString -> Conversion a
668705 go p s =