@@ -1,7 +1,8 @@
1{-# LANGUAGE CPP, DeriveDataTypeable, DeriveFunctor #-}
1{-# LANGUAGE CPP, DeriveDataTypeable, DeriveFunctor #-}
2{-# LANGUAGE FlexibleInstances, TypeSynonymInstances #-}
2{-# LANGUAGE FlexibleInstances, TypeSynonymInstances #-}
3{-# LANGUAGE PatternGuards, ScopedTypeVariables #-}
3{-# LANGUAGE PatternGuards, ScopedTypeVariables #-}
4−{-# LANGUAGE RecordWildCards, TemplateHaskell #-}
4+{-# LANGUAGE RecordWildCards #-}
5+{-# LANGUAGE PolyKinds #-}
7Module: Database.PostgreSQL.Simple.FromField
8Module: Database.PostgreSQL.Simple.FromField
@@ -23,6 +24,24 @@ the Haskell 'Double' type is compatible with the PostgreSQL's 32-bit
23since a 'Double' might lose precision if representing PostgreSQL's 64-bit
24since a 'Double' might lose precision if representing PostgreSQL's 64-bit
24@bigint@, the two are /not/ considered compatible.
25@bigint@, the two are /not/ considered compatible.
27+Note that the 'Float' and 'Double' instances use attoparsec's 'double'
28+conversion routine, which sacrifices some accuracy for speed. If you
29+need accuracy, consider first converting data to a 'Scientific' or 'Rational'
30+type, and then converting to a floating-point type. If you are defining
31+your own 'Database.PostgreSQL.Simple.FromRow.FromRow' instances, this can be
33+@'fromRational' '<$>' 'Database.PostgreSQL.Simple.FromRow.field'@, although
34+this idiom is additionally compatible with PostgreSQL's @int8@ and @numeric@
35+types. If this is unacceptable, you may find
36+'Database.PostgreSQL.Simple.FromRow.fieldWith' useful.
38+Also note that while converting to a 'Double' through the 'Scientific' type
39+is likely somewhat faster than converting through the 'Rational' type,
40+the 'Scientific' type has no way to represent @NaN@ and @±Infinity@ values.
41+Thus, if you need precision conversion of regular floating point values
42+and the possibility of receiving these special values from the backend,
43+stick with 'Rational'.
26Because 'FromField' is a typeclass, one may provide conversions to
45Because 'FromField' is a typeclass, one may provide conversions to
27additional Haskell types without modifying postgresql-simple. This is
46additional Haskell types without modifying postgresql-simple. This is
28particularly useful for supporting PostgreSQL types that postgresql-simple
47particularly useful for supporting PostgreSQL types that postgresql-simple
@@ -87,24 +106,28 @@ module Database.PostgreSQL.Simple.FromField
87 , typeOid
106 , typeOid
88 , PQ.Oid(..)
107 , PQ.Oid(..)
89 , PQ.Format(..)
108 , PQ.Format(..)
109+ , pgArrayFieldParser
91 , fromJSONField
113 , fromJSONField
114+ , fromFieldJSONByteString
94#include "MachDeps.h"
117#include "MachDeps.h"
96−import Control.Applicative
119+import Control.Applicative ( Const(Const), (<|>), (<$>), pure, (*>), (<*) )
97− ( Applicative, (<|>), (<$>), pure )
98import Control.Concurrent.MVar (MVar, newMVar)
120import Control.Concurrent.MVar (MVar, newMVar)
99−import Control.Exception (Exception)
121+import Control.Exception (Exception (toException, fromException))
100import qualified Data.Aeson as JSON
122import qualified Data.Aeson as JSON
101−import Data.Attoparsec.Char8 hiding (Result)
123+import Data.Attoparsec.ByteString.Char8 hiding (Result)
102import Data.ByteString (ByteString)
124import Data.ByteString (ByteString)
103import qualified Data.ByteString.Char8 as B
125import qualified Data.ByteString.Char8 as B
126+import Data.Functor.Identity (Identity(Identity))
104import Data.Int (Int16, Int32, Int64)
127import Data.Int (Int16, Int32, Int64)
105import Data.IORef (IORef, newIORef)
128import Data.IORef (IORef, newIORef)
106import Data.Ratio (Ratio)
129import Data.Ratio (Ratio)
107−import Data.Time ( UTCTime, ZonedTime, LocalTime, Day, TimeOfDay )
130+import Data.Time.Compat ( UTCTime, ZonedTime, LocalTime, Day, TimeOfDay, CalendarDiffTime )
108import Data.Typeable (Typeable, typeOf)
131import Data.Typeable (Typeable, typeOf)
109import Data.Vector (Vector)
132import Data.Vector (Vector)
110import Data.Vector.Mutable (IOVector)
133import Data.Vector.Mutable (IOVector)
@@ -115,7 +138,6 @@ import Database.PostgreSQL.Simple.Ok
115import Database.PostgreSQL.Simple.Types
138import Database.PostgreSQL.Simple.Types
116import Database.PostgreSQL.Simple.TypeInfo as TI
139import Database.PostgreSQL.Simple.TypeInfo as TI
117import qualified Database.PostgreSQL.Simple.TypeInfo.Static as TI
140import qualified Database.PostgreSQL.Simple.TypeInfo.Static as TI
118−import Database.PostgreSQL.Simple.TypeInfo.Macro as TI
119import Database.PostgreSQL.Simple.Time
141import Database.PostgreSQL.Simple.Time
120import Database.PostgreSQL.Simple.Arrays as Arrays
142import Database.PostgreSQL.Simple.Arrays as Arrays
121import qualified Database.PostgreSQL.LibPQ as PQ
143import qualified Database.PostgreSQL.LibPQ as PQ
@@ -125,8 +147,14 @@ import qualified Data.ByteString.Lazy as LB
125import qualified Data.Text as ST
147import qualified Data.Text as ST
126import qualified Data.Text.Encoding as ST
148import qualified Data.Text.Encoding as ST
127import qualified Data.Text.Lazy as LT
149import qualified Data.Text.Lazy as LT
128−import Data.UUID (UUID)
150+import Data.CaseInsensitive (CI)
151+import qualified Data.CaseInsensitive as CI
152+import Data.UUID.Types (UUID)
129−import qualified Data.UUID as UUID
153+import qualified Data.UUID.Types as UUID
154+import Data.Scientific (Scientific)
155+import GHC.Real (infinity, notANumber)
157+import qualified Data.Aeson.Types as JSON
131-- | Exception thrown if conversion from a SQL value to a Haskell
159-- | Exception thrown if conversion from a SQL value to a Haskell
132-- value fails.
160-- value fails.
@@ -154,7 +182,9 @@ data ResultError = Incompatible { errSQLType :: String
154 -- between metadata and actual data in a row).
182 -- between metadata and actual data in a row).
155 deriving (Eq, Show, Typeable)
183 deriving (Eq, Show, Typeable)
157−instance Exception ResultError
185+instance Exception ResultError where
186+ toException = postgresqlExceptionToException
187+ fromException = postgresqlExceptionFromException
159left :: Exception a => a -> Conversion b
189left :: Exception a => a -> Conversion b
160left = conversionError
190left = conversionError
@@ -169,6 +199,16 @@ class FromField a where
169 -- Returns a list of exceptions if the conversion fails. In the case of
199 -- Returns a list of exceptions if the conversion fails. In the case of
170 -- library instances, this will usually be a single 'ResultError', but
200 -- library instances, this will usually be a single 'ResultError', but
171 -- may be a 'UnicodeException'.
201 -- may be a 'UnicodeException'.
203+ -- Note that retaining any reference to the 'Field' argument causes
204+ -- the entire @LibPQ.'PQ.Result'@ to be retained. Thus, implementations
205+ -- of 'fromField' should return results that do not refer to this value
206+ -- after the result have been evaluated to WHNF.
208+ -- Note that as of @postgresql-simple-0.4.0.0@, the 'ByteString' value
209+ -- has already been copied out of the @LibPQ.'PQ.Result'@ before it has
210+ -- been passed to 'fromField'. This is because for short strings, it's
211+ -- cheaper to copy the string than to set up a finalizer.
173-- | Returns the data type name. This is the preferred way of identifying
213-- | Returns the data type name. This is the preferred way of identifying
174-- types that do not have a stable type oid, such as types provided by
214-- types that do not have a stable type oid, such as types provided by
@@ -185,7 +225,7 @@ typename field = typname <$> typeInfo field
186typeInfo :: Field -> Conversion TypeInfo
226typeInfo :: Field -> Conversion TypeInfo
187typeInfo Field{..} = Conversion $ \conn -> do
227typeInfo Field{..} = Conversion $ \conn -> do
188− Ok <$> (getTypeInfo conn =<< PQ.ftype result column)
228+ Ok <$> (getTypeInfo conn typeOid)
190typeInfoByOid :: PQ.Oid -> Conversion TypeInfo
230typeInfoByOid :: PQ.Oid -> Conversion TypeInfo
191typeInfoByOid oid = Conversion $ \conn -> do
231typeInfoByOid oid = Conversion $ \conn -> do
@@ -210,9 +250,11 @@ tableOid Field{..} = toMaybeOid (unsafeDupablePerformIO (PQ.ftable result column
210 then Nothing
250 then Nothing
211 else Just x
251 else Just x
213−-- | If the column has a table associated with it, this returns the number
253+-- | If the column has a table associated with it, this returns the
214−-- off the associated table column. Numbering starts from 0. Analogous
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
215−-- to libpq's @PQftablecol@.
257+-- protocol. Analogous to libpq's @PQftablecol@.
217tableColumn :: Field -> Int
259tableColumn :: Field -> Int
218tableColumn Field{..} = fromCol (unsafeDupablePerformIO (PQ.ftablecol result column))
260tableColumn Field{..} = fromCol (unsafeDupablePerformIO (PQ.ftablecol result column))
@@ -228,16 +270,33 @@ format Field{..} = unsafeDupablePerformIO (PQ.fformat result column)
229instance FromField () where
271instance FromField () where
230 fromField f _bs
272 fromField f _bs
231− | typeOid f /= $(inlineTypoid TI.void) = returnError Incompatible f ""
273+ | typeOid f /= TI.voidOid = returnError Incompatible f ""
232 | otherwise = pure ()
274 | otherwise = pure ()
276+instance (FromField a) => FromField (Const a b) where
277+ fromField f bs = Const <$> fromField f bs
279+instance (FromField a) => FromField (Identity a) where
280+ fromField f bs = Identity <$> fromField f bs
234-- | For dealing with null values. Compatible with any postgresql type
282-- | For dealing with null values. Compatible with any postgresql type
235-- compatible with type @a@. Note that the type is not checked if
283-- compatible with type @a@. Note that the type is not checked if
236-- the value is null, although it is inadvisable to rely on this
284-- the value is null, although it is inadvisable to rely on this
237-- behavior.
285-- behavior.
238−instance (FromField a) => FromField (Maybe a) where
286+instance FromField a => FromField (Maybe a) where
287+ fromField = optionalField fromField
289+-- | For dealing with SQL @null@ values outside of the 'FromField' class.
290+-- Alternatively, one could use 'Control.Applicative.optional', but that
291+-- also turns type and conversion errors into 'Nothing', whereas this is
292+-- more specific and turns only @null@ values into 'Nothing'.
294+optionalField :: FieldParser a -> FieldParser (Maybe a)
295+optionalField p f mv =
239− fromField _ Nothing = pure Nothing
297+ Nothing -> pure Nothing
240− fromField f bs = Just <$> fromField f bs
298+ Just _ -> Just <$> p f mv
299+{-# INLINE optionalField #-}
242-- | compatible with any data type, but the value must be null
301-- | compatible with any data type, but the value must be null
243instance FromField Null where
302instance FromField Null where
@@ -247,30 +306,30 @@ instance FromField Null where
248instance FromField Bool where
307instance FromField Bool where
249 fromField f bs
308 fromField f bs
250− | typeOid f /= $(inlineTypoid TI.bool) = returnError Incompatible f ""
309+ | typeOid f /= TI.boolOid = returnError Incompatible f ""
251 | bs == Nothing = returnError UnexpectedNull f ""
310 | bs == Nothing = returnError UnexpectedNull f ""
252 | bs == Just "t" = pure True
311 | bs == Just "t" = pure True
253 | bs == Just "f" = pure False
312 | bs == Just "f" = pure False
254 | otherwise = returnError ConversionFailed f ""
313 | otherwise = returnError ConversionFailed f ""
256−-- | \"char\"
315+-- | \"char\", bpchar
257instance FromField Char where
316instance FromField Char where
258− fromField f bs =
317+ fromField f bs0 =
259− if typeOid f /= $(inlineTypoid TI.char)
318+ if (eq TI.charOid \/ eq TI.bpcharOid) (typeOid f)
260− then returnError Incompatible f ""
261− else case bs of
319+ then case bs0 of
262 Nothing -> returnError UnexpectedNull f ""
320 Nothing -> returnError UnexpectedNull f ""
263 Just bs -> if B.length bs /= 1
321 Just bs -> if B.length bs /= 1
264 then returnError ConversionFailed f "length not 1"
322 then returnError ConversionFailed f "length not 1"
265 else return $! (B.head bs)
323 else return $! (B.head bs)
324+ else returnError Incompatible f ""
268instance FromField Int16 where
327instance FromField Int16 where
269− fromField = atto ok16 $ signed decimal
328+ fromField = attoFieldParser ok16 $ signed decimal
271-- | int2, int4
330-- | int2, int4
272instance FromField Int32 where
331instance FromField Int32 where
273− fromField = atto ok32 $ signed decimal
332+ fromField = attoFieldParser ok32 $ signed decimal
275#if WORD_SIZE_IN_BITS < 64
334#if WORD_SIZE_IN_BITS < 64
276-- | int2, int4, and if compiled as 64-bit code, int8 as well.
335-- | int2, int4, and if compiled as 64-bit code, int8 as well.
@@ -280,43 +339,64 @@ instance FromField Int32 where
280-- This library was compiled as 64-bit code.
339-- This library was compiled as 64-bit code.
282instance FromField Int where
341instance FromField Int where
283− fromField = atto okInt $ signed decimal
342+ fromField = attoFieldParser okInt $ signed decimal
285-- | int2, int4, int8
344-- | int2, int4, int8
286instance FromField Int64 where
345instance FromField Int64 where
287− fromField = atto ok64 $ signed decimal
346+ fromField = attoFieldParser ok64 $ signed decimal
289-- | int2, int4, int8
348-- | int2, int4, int8
290instance FromField Integer where
349instance FromField Integer where
291− fromField = atto ok64 $ signed decimal
350+ fromField = attoFieldParser ok64 $ signed decimal
293−-- | int2, float4
352+-- | int2, float4 (Uses attoparsec's 'double' routine, for
353+-- better accuracy convert to 'Scientific' or 'Rational' first)
294instance FromField Float where
354instance FromField Float where
295− fromField = atto ok (realToFrac <$> double)
355+ fromField = attoFieldParser ok (realToFrac <$> pg_double)
296− where ok = $(mkCompats [TI.float4,TI.int2])
356+ where ok = eq TI.float4Oid \/ eq TI.int2Oid
298−-- | int2, int4, float4, float8
358+-- | int2, int4, float4, float8 (Uses attoparsec's 'double' routine, for
359+-- better accuracy convert to 'Scientific' or 'Rational' first)
299instance FromField Double where
360instance FromField Double where
300− fromField = atto ok double
361+ fromField = attoFieldParser ok pg_double
301− where ok = $(mkCompats [TI.float4,TI.float8,TI.int2,TI.int4])
362+ where ok = eq TI.float4Oid \/ eq TI.float8Oid \/ eq TI.int2Oid \/ eq TI.int4Oid
303−-- | int2, int4, float4, float8, numeric
364+-- | int2, int4, int8, float4, float8, numeric
304instance FromField (Ratio Integer) where
365instance FromField (Ratio Integer) where
305− fromField = atto ok rational
366+ fromField = attoFieldParser ok pg_rational
306− where ok = $(mkCompats [TI.float4,TI.float8,TI.int2,TI.int4,TI.numeric])
367+ where ok = eq TI.float4Oid \/ eq TI.float8Oid \/ eq TI.int2Oid \/ eq TI.int4Oid \/ eq TI.int8Oid \/ eq TI.numericOid
369+-- | int2, int4, int8, float4, float8, numeric
370+instance FromField Scientific where
371+ fromField = attoFieldParser ok rational
372+ where ok = eq TI.float4Oid \/ eq TI.float8Oid \/ eq TI.int2Oid \/ eq TI.int4Oid \/ eq TI.int8Oid \/ eq TI.numericOid
308unBinary :: Binary t -> t
374unBinary :: Binary t -> t
309unBinary (Binary x) = x
375unBinary (Binary x) = x
377+pg_double :: Parser Double
379+ = (string "NaN" *> pure ( 0 / 0))
380+ <|> (string "Infinity" *> pure ( 1 / 0))
381+ <|> (string "-Infinity" *> pure (-1 / 0))
384+pg_rational :: Parser Rational
386+ = (string "NaN" *> pure notANumber )
387+ <|> (string "Infinity" *> pure infinity )
388+ <|> (string "-Infinity" *> pure (-infinity))
311-- | bytea, name, text, \"char\", bpchar, varchar, unknown
391-- | bytea, name, text, \"char\", bpchar, varchar, unknown
312instance FromField SB.ByteString where
392instance FromField SB.ByteString where
313− fromField f dat = if typeOid f == $(inlineTypoid TI.bytea)
393+ fromField f dat = if typeOid f == TI.byteaOid
314 then unBinary <$> fromField f dat
394 then unBinary <$> fromField f dat
315 else doFromField f okText' pure dat
395 else doFromField f okText' pure dat
318instance FromField PQ.Oid where
398instance FromField PQ.Oid where
319− fromField f dat = PQ.Oid <$> atto (== $(inlineTypoid TI.oid)) decimal f dat
399+ fromField f dat = PQ.Oid <$> attoFieldParser (== TI.oidOid) decimal f dat
321-- | bytea, name, text, \"char\", bpchar, varchar, unknown
401-- | bytea, name, text, \"char\", bpchar, varchar, unknown
322instance FromField LB.ByteString where
402instance FromField LB.ByteString where
@@ -324,7 +404,7 @@ instance FromField LB.ByteString where
325unescapeBytea :: Field -> SB.ByteString
405unescapeBytea :: Field -> SB.ByteString
326 -> Conversion (Binary SB.ByteString)
406 -> Conversion (Binary SB.ByteString)
327−unescapeBytea f str = case unsafeDupablePerformIO (PQ.unescapeBytea str) of
407+unescapeBytea f str' = case unsafeDupablePerformIO (PQ.unescapeBytea str') of
328 Nothing -> returnError ConversionFailed f "unescapeBytea failed"
408 Nothing -> returnError ConversionFailed f "unescapeBytea failed"
329 Just str -> pure (Binary str)
409 Just str -> pure (Binary str)
@@ -347,54 +427,85 @@ instance FromField ST.Text where
347instance FromField LT.Text where
427instance FromField LT.Text where
348 fromField f dat = LT.fromStrict <$> fromField f dat
428 fromField f dat = LT.fromStrict <$> fromField f dat
431+instance FromField (CI ST.Text) where
432+ fromField f mdat = do
435+ then returnError Incompatible f ""
437+ Nothing -> returnError UnexpectedNull f ""
438+ Just dat -> either left (pure . CI.mk)
439+ (ST.decodeUtf8' dat)
442+instance FromField (CI LT.Text) where
443+ fromField f mdat = do
446+ then returnError Incompatible f ""
448+ Nothing -> returnError UnexpectedNull f ""
449+ Just dat -> either left (pure . CI.mk . LT.fromStrict)
450+ (ST.decodeUtf8' dat)
350-- | name, text, \"char\", bpchar, varchar
452-- | name, text, \"char\", bpchar, varchar
351instance FromField [Char] where
453instance FromField [Char] where
352 fromField f dat = ST.unpack <$> fromField f dat
454 fromField f dat = ST.unpack <$> fromField f dat
354-- | timestamptz
456-- | timestamptz
355instance FromField UTCTime where
457instance FromField UTCTime where
356− fromField = ff $(inlineTypoid TI.timestamptz) "UTCTime" parseUTCTime
458+ fromField = ff TI.timestamptzOid "UTCTime" parseUTCTime
358-- | timestamptz
460-- | timestamptz
359instance FromField ZonedTime where
461instance FromField ZonedTime where
360− fromField = ff $(inlineTypoid TI.timestamptz) "ZonedTime" parseZonedTime
462+ fromField = ff TI.timestamptzOid "ZonedTime" parseZonedTime
362-- | timestamp
464-- | timestamp
363instance FromField LocalTime where
465instance FromField LocalTime where
364− fromField = ff $(inlineTypoid TI.timestamp) "LocalTime" parseLocalTime
466+ fromField = ff TI.timestampOid "LocalTime" parseLocalTime
367instance FromField Day where
469instance FromField Day where
368− fromField = ff $(inlineTypoid TI.date) "Day" parseDay
470+ fromField = ff TI.dateOid "Day" parseDay
371instance FromField TimeOfDay where
473instance FromField TimeOfDay where
372− fromField = ff $(inlineTypoid TI.time) "TimeOfDay" parseTimeOfDay
474+ fromField = ff TI.timeOid "TimeOfDay" parseTimeOfDay
374-- | timestamptz
476-- | timestamptz
375instance FromField UTCTimestamp where
477instance FromField UTCTimestamp where
376− fromField = ff $(inlineTypoid TI.timestamptz) "UTCTimestamp" parseUTCTimestamp
478+ fromField = ff TI.timestamptzOid "UTCTimestamp" parseUTCTimestamp
378-- | timestamptz
480-- | timestamptz
379instance FromField ZonedTimestamp where
481instance FromField ZonedTimestamp where
380− fromField = ff $(inlineTypoid TI.timestamptz) "ZonedTimestamp" parseZonedTimestamp
482+ fromField = ff TI.timestamptzOid "ZonedTimestamp" parseZonedTimestamp
382-- | timestamp
484-- | timestamp
383instance FromField LocalTimestamp where
485instance FromField LocalTimestamp where
384− fromField = ff $(inlineTypoid TI.timestamp) "LocalTimestamp" parseLocalTimestamp
486+ fromField = ff TI.timestampOid "LocalTimestamp" parseLocalTimestamp
387instance FromField Date where
489instance FromField Date where
388− fromField = ff $(inlineTypoid TI.date) "Date" parseDate
490+ fromField = ff TI.dateOid "Date" parseDate
492+-- | interval. Requires you to configure intervalstyle as @iso_8601@.
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;@ .
498+instance FromField CalendarDiffTime where
499+ fromField = ff TI.intervalOid "CalendarDiffTime" parseCalendarDiffTime
390ff :: PQ.Oid -> String -> (B8.ByteString -> Either String a)
501ff :: PQ.Oid -> String -> (B8.ByteString -> Either String a)
391 -> Field -> Maybe B8.ByteString -> Conversion a
502 -> Field -> Maybe B8.ByteString -> Conversion a
392−ff compatOid hsType parse f mstr =
503+ff compatOid hsType parseBS f mstr =
393 if typeOid f /= compatOid
504 if typeOid f /= compatOid
394 then err Incompatible ""
505 then err Incompatible ""
395 else case mstr of
506 else case mstr of
396 Nothing -> err UnexpectedNull ""
507 Nothing -> err UnexpectedNull ""
397− Just str -> case parse str of
508+ Just str -> case parseBS str of
398 Left msg -> err ConversionFailed msg
509 Left msg -> err ConversionFailed msg
399 Right val -> return val
510 Right val -> return val
@@ -416,27 +527,33 @@ instance (FromField a, FromField b) => FromField (Either a b) where
417-- | any postgresql array whose elements are compatible with type @a@
528-- | any postgresql array whose elements are compatible with type @a@
418instance (FromField a, Typeable a) => FromField (PGArray a) where
529instance (FromField a, Typeable a) => FromField (PGArray a) where
419− fromField f mdat = do
530+ fromField = pgArrayFieldParser fromField
532+pgArrayFieldParser :: Typeable a => FieldParser a -> FieldParser (PGArray a)
533+pgArrayFieldParser fieldParser f mdat = do
420 info <- typeInfo f
534 info <- typeInfo f
421 case info of
535 case info of
422 TI.Array{} ->
536 TI.Array{} ->
423 case mdat of
537 case mdat of
424 Nothing -> returnError UnexpectedNull f ""
538 Nothing -> returnError UnexpectedNull f ""
425 Just dat -> do
539 Just dat -> do
426− case parseOnly (fromArray info f) dat of
540+ case parseOnly (fromArray fieldParser info f) dat of
427 Left err -> returnError ConversionFailed f err
541 Left err -> returnError ConversionFailed f err
428 Right conv -> PGArray <$> conv
542 Right conv -> PGArray <$> conv
429 _ -> returnError Incompatible f ""
543 _ -> returnError Incompatible f ""
431−fromArray :: (FromField a)
432− => TypeInfo -> Field -> Parser (Conversion [a])
545+fromArray :: FieldParser a -> TypeInfo -> Field -> Parser (Conversion [a])
433−fromArray typeInfo f = sequence . (parseIt <$>) <$> array delim
546+fromArray fieldParser typInfo f = sequence . (parseIt <$>) <$> array delim
435− delim = typdelim (typelem typeInfo)
548+ delim = typdelim (typelem typInfo)
436− fElem = f{ typeOid = typoid (typelem typeInfo) }
549+ fElem = f{ typeOid = typoid (typelem typInfo) }
437− parseIt item = (fromField f' . Just . fmt delim) item
551+ parseIt item =
552+ fieldParser f' $ if item == Arrays.Plain "NULL" then Nothing else Just item'
554+ item' = fmt delim item
438− where f' | Arrays.Array _ <- item = f
555+ f' | Arrays.Array _ <- item = f
439− | otherwise = fElem
556+ | otherwise = fElem
441instance (FromField a, Typeable a) => FromField (Vector a) where
558instance (FromField a, Typeable a) => FromField (Vector a) where
442 fromField f v = V.fromList . fromPGArray <$> fromField f v
559 fromField f v = V.fromList . fromPGArray <$> fromField f v
@@ -447,7 +564,7 @@ instance (FromField a, Typeable a) => FromField (IOVector a) where
448instance FromField UUID where
565instance FromField UUID where
449 fromField f mbs =
566 fromField f mbs =
450− if typeOid f /= $(inlineTypoid TI.uuid)
567+ if typeOid f /= TI.uuidOid
451 then returnError Incompatible f ""
568 then returnError Incompatible f ""
452 else case mbs of
569 else case mbs of
453 Nothing -> returnError UnexpectedNull f ""
570 Nothing -> returnError UnexpectedNull f ""
@@ -456,26 +573,26 @@ instance FromField UUID where
456 Nothing -> returnError ConversionFailed f "Invalid UUID"
573 Nothing -> returnError ConversionFailed f "Invalid UUID"
457 Just uuid -> pure uuid
574 Just uuid -> pure uuid
459−-- | json
576+-- | json, jsonb
460instance FromField JSON.Value where
577instance FromField JSON.Value where
461− fromField f mbs =
578+ fromField f mbs = parseBS =<< fromFieldJSONByteString f mbs
462− if typeOid f /= $(inlineTypoid TI.json)
579+ where parseBS bs = case JSON.eitherDecodeStrict' bs of
580+ Left err -> returnError ConversionFailed f err
581+ Right val -> pure val
583+-- | Return the JSON ByteString directly
586+fromFieldJSONByteString :: Field -> Maybe ByteString -> Conversion ByteString
587+fromFieldJSONByteString f mbs =
588+ if typeOid f /= TI.jsonOid && typeOid f /= TI.jsonbOid
463 then returnError Incompatible f ""
589 then returnError Incompatible f ""
464 else case mbs of
590 else case mbs of
465 Nothing -> returnError UnexpectedNull f ""
591 Nothing -> returnError UnexpectedNull f ""
466− Just bs ->
592+ Just bs -> pure bs
467−#if MIN_VERSION_aeson(0,6,3)
468− case JSON.eitherDecodeStrict' bs of
469−#elsif MIN_VERSION_bytestring(0,10,0)
470− case JSON.eitherDecode' $ LB.fromStrict bs of
472− case JSON.eitherDecode' $ LB.fromChunks [bs] of
474− Left err -> returnError ConversionFailed f err
475− Right val -> pure val
477-- | Parse a field to a JSON 'JSON.Value' and convert that into a
594-- | Parse a field to a JSON 'JSON.Value' and convert that into a
478−-- Haskell value using 'JSON.fromJSON'.
595+-- Haskell value using the 'JSON.FromJSON' instance.
480-- This can be used as the default implementation for the 'fromField'
597-- This can be used as the default implementation for the 'fromField'
481-- method for Haskell types that have a JSON representation in
598-- method for Haskell types that have a JSON representation in
@@ -483,14 +600,23 @@ instance FromField JSON.Value where
484-- The 'Typeable' constraint is required to show more informative
601-- The 'Typeable' constraint is required to show more informative
485-- error messages when parsing fails.
602-- error messages when parsing fails.
604+-- Note that @fromJSONField :: FieldParser ('Maybe' Foo)@ will return
605+-- @'Nothing'@ on the json @null@ value, and return an exception on SQL @null@
606+-- value. Alternatively, one could write @'optionalField' fromJSONField@
607+-- that will return @Nothing@ on SQL @null@, and otherwise will call
608+-- @fromJSONField :: FieldParser Foo@ and then return @'Just'@ the
609+-- result value, or return its exception. If one would
610+-- like to return @Nothing@ on both the SQL @null@ and json @null@ values,
611+-- one way to do it would be to write
612+-- @\\f mv -> 'Control.Monad.join' '<$>' optionalField fromJSONField f mv@
486fromJSONField :: (JSON.FromJSON a, Typeable a) => FieldParser a
613fromJSONField :: (JSON.FromJSON a, Typeable a) => FieldParser a
487fromJSONField f mbBs = do
614fromJSONField f mbBs = do
488 value <- fromField f mbBs
615 value <- fromField f mbBs
489− case JSON.fromJSON value of
616+ case JSON.ifromJSON value of
490− JSON.Error err -> returnError ConversionFailed f $
617+ JSON.IError path err -> returnError ConversionFailed f $
491− "JSON decoding error: " ++ err
618+ "JSON decoding error: " ++ (JSON.formatError path err)
492− JSON.Success x -> pure x
619+ JSON.ISuccess x -> pure x
495-- | Compatible with the same set of types as @a@. Note that
621-- | Compatible with the same set of types as @a@. Note that
496-- modifying the 'IORef' does not have any effects outside
622-- modifying the 'IORef' does not have any effects outside
@@ -507,20 +633,33 @@ instance FromField a => FromField (MVar a) where
507type Compat = PQ.Oid -> Bool
633type Compat = PQ.Oid -> Bool
509okText, okText', okBinary, ok16, ok32, ok64, okInt :: Compat
635okText, okText', okBinary, ok16, ok32, ok64, okInt :: Compat
510−okText = $( mkCompats [ TI.name, TI.text, TI.char,
636+okText = eq TI.nameOid \/ eq TI.textOid \/ eq TI.charOid
511− TI.bpchar, TI.varchar ] )
637+ \/ eq TI.bpcharOid \/ eq TI.varcharOid
512−okText' = $( mkCompats [ TI.name, TI.text, TI.char,
638+okText' = eq TI.nameOid \/ eq TI.textOid \/ eq TI.charOid
513− TI.bpchar, TI.varchar, TI.unknown ] )
639+ \/ eq TI.bpcharOid \/ eq TI.varcharOid \/ eq TI.unknownOid
514−okBinary = (== $( inlineTypoid TI.bytea ))
640+okBinary = eq TI.byteaOid
515−ok16 = (== $( inlineTypoid TI.int2 ))
641+ok16 = eq TI.int2Oid
516−ok32 = $( mkCompats [TI.int2,TI.int4] )
642+ok32 = eq TI.int2Oid \/ eq TI.int4Oid
517−ok64 = $( mkCompats [TI.int2,TI.int4,TI.int8] )
643+ok64 = eq TI.int2Oid \/ eq TI.int4Oid \/ eq TI.int8Oid
518#if WORD_SIZE_IN_BITS < 64
644#if WORD_SIZE_IN_BITS < 64
519okInt = ok32
645okInt = ok32
521okInt = ok64
647okInt = ok64
650+-- | eq and \/ are used to imlement what Macro stuff did,
651+-- i.e. mkCompats and inlineTypoid
652+eq :: PQ.Oid -> PQ.Oid -> Bool
657+(\/) :: (PQ.Oid -> Bool)
660+f \/ g = \x -> f x || g x
524doFromField :: forall a . (Typeable a)
663doFromField :: forall a . (Typeable a)
525 => Field -> Compat -> (ByteString -> Conversion a)
664 => Field -> Compat -> (ByteString -> Conversion a)
526 -> Maybe ByteString -> Conversion a
665 -> Maybe ByteString -> Conversion a
@@ -545,10 +684,22 @@ returnError mkErr f msg = do
545 (show (typeOf (undefined :: a)))
684 (show (typeOf (undefined :: a)))
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.
691+-- instance FromField Int16 where
692+-- fromField = attoFieldParser ok16 (signed decimal)
548−atto :: forall a. (Typeable a)
696+attoFieldParser :: forall a. (Typeable a)
549− => Compat -> Parser a -> Field -> Maybe ByteString
697+ => (PQ.Oid -> Bool)
550− -> Conversion a
698+ -- ^ Predicate for whether the postgresql type oid is compatible with this parser
700+ -- ^ An attoparsec parser.
551−atto types p0 f dat = doFromField f types (go p0) dat
702+attoFieldParser types p0 f dat = doFromField f types (go p0) dat
553 go :: Parser a -> ByteString -> Conversion a
704 go :: Parser a -> ByteString -> Conversion a