@@ -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' '<$>' 'Database.PostgreSQL.Simple.FromRow.field'@, although
34+this idiom is additionally compatible with PostgreSQL's @int8@ and @numeric@
35+types. If this is unacceptable, you may find
36+'Database.PostgreSQL.Simple.FromRow.fieldWith' useful.
38+Also note that while converting to a 'Double' through the 'Scientific' type
39+is likely somewhat faster than converting through the 'Rational' type,
40+the 'Scientific' type has no way to represent @NaN@ and @±Infinity@ values.
41+Thus, if you need precision conversion of regular floating point values
42+and the possibility of receiving these special values from the backend,
43+stick with 'Rational'.
26Because 'FromField' is a typeclass, one may provide conversions to
45Because 'FromField' is a typeclass, one may provide conversions to
27additional Haskell types without modifying postgresql-simple. This is
46additional Haskell types without modifying postgresql-simple. This is
28particularly useful for supporting PostgreSQL types that postgresql-simple
47particularly useful for supporting PostgreSQL types that postgresql-simple
@@ -87,34 +106,38 @@ module Database.PostgreSQL.Simple.FromField
87 , typeOid
106 , typeOid
88 , PQ.Oid(..)
107 , PQ.Oid(..)
89 , PQ.Format(..)
108 , PQ.Format(..)
109+ , pgArrayFieldParser
91 , fromJSONField
113 , fromJSONField
114+ , fromFieldJSONByteString
94#include "MachDeps.h"
117#include "MachDeps.h"
96−import Control.Applicative
119+import Control.Applicative ( Const(Const), (<|>), (<$>), 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)
133+import Data.Vector.Mutable (IOVector)
110import qualified Data.Vector as V
134import qualified Data.Vector as V
111import Database.PostgreSQL.Simple.Internal
135import Database.PostgreSQL.Simple.Internal
112import Database.PostgreSQL.Simple.Compat
136import Database.PostgreSQL.Simple.Compat
113import Database.PostgreSQL.Simple.Ok
137import Database.PostgreSQL.Simple.Ok
114−import Database.PostgreSQL.Simple.Types (Binary(..), Null(..))
138+import Database.PostgreSQL.Simple.Types
115import Database.PostgreSQL.Simple.TypeInfo as TI
139import Database.PostgreSQL.Simple.TypeInfo as TI
116import qualified Database.PostgreSQL.Simple.TypeInfo.Static as TI
140import qualified Database.PostgreSQL.Simple.TypeInfo.Static as TI
117−import Database.PostgreSQL.Simple.TypeInfo.Macro as TI
118import Database.PostgreSQL.Simple.Time
141import Database.PostgreSQL.Simple.Time
119import Database.PostgreSQL.Simple.Arrays as Arrays
142import Database.PostgreSQL.Simple.Arrays as Arrays
120import qualified Database.PostgreSQL.LibPQ as PQ
143import qualified Database.PostgreSQL.LibPQ as PQ
@@ -124,8 +147,14 @@ import qualified Data.ByteString.Lazy as LB
124import qualified Data.Text as ST
147import qualified Data.Text as ST
125import qualified Data.Text.Encoding as ST
148import qualified Data.Text.Encoding as ST
126import qualified Data.Text.Lazy as LT
149import qualified Data.Text.Lazy as LT
127−import Data.UUID (UUID)
150+import Data.CaseInsensitive (CI)
151+import qualified Data.CaseInsensitive as CI
152+import Data.UUID.Types (UUID)
128−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
130-- | Exception thrown if conversion from a SQL value to a Haskell
159-- | Exception thrown if conversion from a SQL value to a Haskell
131-- value fails.
160-- value fails.
@@ -153,7 +182,9 @@ data ResultError = Incompatible { errSQLType :: String
153 -- between metadata and actual data in a row).
182 -- between metadata and actual data in a row).
154 deriving (Eq, Show, Typeable)
183 deriving (Eq, Show, Typeable)
156−instance Exception ResultError
185+instance Exception ResultError where
186+ toException = postgresqlExceptionToException
187+ fromException = postgresqlExceptionFromException
158left :: Exception a => a -> Conversion b
189left :: Exception a => a -> Conversion b
159left = conversionError
190left = conversionError
@@ -168,6 +199,16 @@ class FromField a where
168 -- 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
169 -- library instances, this will usually be a single 'ResultError', but
200 -- library instances, this will usually be a single 'ResultError', but
170 -- 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.
172-- | 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
173-- 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
@@ -184,7 +225,7 @@ typename field = typname <$> typeInfo field
185typeInfo :: Field -> Conversion TypeInfo
226typeInfo :: Field -> Conversion TypeInfo
186typeInfo Field{..} = Conversion $ \conn -> do
227typeInfo Field{..} = Conversion $ \conn -> do
187− Ok <$> (getTypeInfo conn =<< PQ.ftype result column)
228+ Ok <$> (getTypeInfo conn typeOid)
189typeInfoByOid :: PQ.Oid -> Conversion TypeInfo
230typeInfoByOid :: PQ.Oid -> Conversion TypeInfo
190typeInfoByOid oid = Conversion $ \conn -> do
231typeInfoByOid oid = Conversion $ \conn -> do
@@ -209,9 +250,11 @@ tableOid Field{..} = toMaybeOid (unsafeDupablePerformIO (PQ.ftable result column
209 then Nothing
250 then Nothing
210 else Just x
251 else Just x
212−-- | 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
213−-- 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
214−-- to libpq's @PQftablecol@.
257+-- protocol. Analogous to libpq's @PQftablecol@.
216tableColumn :: Field -> Int
259tableColumn :: Field -> Int
217tableColumn Field{..} = fromCol (unsafeDupablePerformIO (PQ.ftablecol result column))
260tableColumn Field{..} = fromCol (unsafeDupablePerformIO (PQ.ftablecol result column))
@@ -227,16 +270,33 @@ format Field{..} = unsafeDupablePerformIO (PQ.fformat result column)
228instance FromField () where
271instance FromField () where
229 fromField f _bs
272 fromField f _bs
230− | typeOid f /= $(inlineTypoid TI.void) = returnError Incompatible f ""
273+ | typeOid f /= TI.voidOid = returnError Incompatible f ""
231 | otherwise = pure ()
274 | otherwise = pure ()
276+instance (FromField a) => FromField (Const a b) where
277+ fromField f bs = Const <$> fromField f bs
279+instance (FromField a) => FromField (Identity a) where
280+ fromField f bs = Identity <$> fromField f bs
233-- | For dealing with null values. Compatible with any postgresql type
282-- | For dealing with null values. Compatible with any postgresql type
234-- compatible with type @a@. Note that the type is not checked if
283-- compatible with type @a@. Note that the type is not checked if
235-- the value is null, although it is inadvisable to rely on this
284-- the value is null, although it is inadvisable to rely on this
236-- behavior.
285-- behavior.
237−instance (FromField a) => FromField (Maybe a) where
286+instance FromField a => FromField (Maybe a) where
287+ fromField = optionalField fromField
289+-- | For dealing with SQL @null@ values outside of the 'FromField' class.
290+-- Alternatively, one could use 'Control.Applicative.optional', but that
291+-- also turns type and conversion errors into 'Nothing', whereas this is
292+-- more specific and turns only @null@ values into 'Nothing'.
294+optionalField :: FieldParser a -> FieldParser (Maybe a)
295+optionalField p f mv =
238− fromField _ Nothing = pure Nothing
297+ Nothing -> pure Nothing
239− fromField f bs = Just <$> fromField f bs
298+ Just _ -> Just <$> p f mv
299+{-# INLINE optionalField #-}
241-- | compatible with any data type, but the value must be null
301-- | compatible with any data type, but the value must be null
242instance FromField Null where
302instance FromField Null where
@@ -246,30 +306,30 @@ instance FromField Null where
247instance FromField Bool where
307instance FromField Bool where
248 fromField f bs
308 fromField f bs
249− | typeOid f /= $(inlineTypoid TI.bool) = returnError Incompatible f ""
309+ | typeOid f /= TI.boolOid = returnError Incompatible f ""
250 | bs == Nothing = returnError UnexpectedNull f ""
310 | bs == Nothing = returnError UnexpectedNull f ""
251 | bs == Just "t" = pure True
311 | bs == Just "t" = pure True
252 | bs == Just "f" = pure False
312 | bs == Just "f" = pure False
253 | otherwise = returnError ConversionFailed f ""
313 | otherwise = returnError ConversionFailed f ""
255−-- | \"char\"
315+-- | \"char\", bpchar
256instance FromField Char where
316instance FromField Char where
257− fromField f bs =
317+ fromField f bs0 =
258− if typeOid f /= $(inlineTypoid TI.char)
318+ if (eq TI.charOid \/ eq TI.bpcharOid) (typeOid f)
259− then returnError Incompatible f ""
260− else case bs of
319+ then case bs0 of
261 Nothing -> returnError UnexpectedNull f ""
320 Nothing -> returnError UnexpectedNull f ""
262 Just bs -> if B.length bs /= 1
321 Just bs -> if B.length bs /= 1
263 then returnError ConversionFailed f "length not 1"
322 then returnError ConversionFailed f "length not 1"
264 else return $! (B.head bs)
323 else return $! (B.head bs)
324+ else returnError Incompatible f ""
267instance FromField Int16 where
327instance FromField Int16 where
268− fromField = atto ok16 $ signed decimal
328+ fromField = attoFieldParser ok16 $ signed decimal
270-- | int2, int4
330-- | int2, int4
271instance FromField Int32 where
331instance FromField Int32 where
272− fromField = atto ok32 $ signed decimal
332+ fromField = attoFieldParser ok32 $ signed decimal
274#if WORD_SIZE_IN_BITS < 64
334#if WORD_SIZE_IN_BITS < 64
275-- | 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.
@@ -279,43 +339,64 @@ instance FromField Int32 where
279-- This library was compiled as 64-bit code.
339-- This library was compiled as 64-bit code.
281instance FromField Int where
341instance FromField Int where
282− fromField = atto okInt $ signed decimal
342+ fromField = attoFieldParser okInt $ signed decimal
284-- | int2, int4, int8
344-- | int2, int4, int8
285instance FromField Int64 where
345instance FromField Int64 where
286− fromField = atto ok64 $ signed decimal
346+ fromField = attoFieldParser ok64 $ signed decimal
288-- | int2, int4, int8
348-- | int2, int4, int8
289instance FromField Integer where
349instance FromField Integer where
290− fromField = atto ok64 $ signed decimal
350+ fromField = attoFieldParser ok64 $ signed decimal
292−-- | int2, float4
352+-- | int2, float4 (Uses attoparsec's 'double' routine, for
353+-- better accuracy convert to 'Scientific' or 'Rational' first)
293instance FromField Float where
354instance FromField Float where
294− fromField = atto ok (realToFrac <$> double)
355+ fromField = attoFieldParser ok (realToFrac <$> pg_double)
295− where ok = $(mkCompats [TI.float4,TI.int2])
356+ where ok = eq TI.float4Oid \/ eq TI.int2Oid
297−-- | int2, int4, float4, float8
358+-- | int2, int4, float4, float8 (Uses attoparsec's 'double' routine, for
359+-- better accuracy convert to 'Scientific' or 'Rational' first)
298instance FromField Double where
360instance FromField Double where
299− fromField = atto ok double
361+ fromField = attoFieldParser ok pg_double
300− 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
302−-- | int2, int4, float4, float8, numeric
364+-- | int2, int4, int8, float4, float8, numeric
303instance FromField (Ratio Integer) where
365instance FromField (Ratio Integer) where
304− fromField = atto ok rational
366+ fromField = attoFieldParser ok pg_rational
305− 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
307unBinary :: Binary t -> t
374unBinary :: Binary t -> t
308unBinary (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))
310-- | bytea, name, text, \"char\", bpchar, varchar, unknown
391-- | bytea, name, text, \"char\", bpchar, varchar, unknown
311instance FromField SB.ByteString where
392instance FromField SB.ByteString where
312− fromField f dat = if typeOid f == $(inlineTypoid TI.bytea)
393+ fromField f dat = if typeOid f == TI.byteaOid
313 then unBinary <$> fromField f dat
394 then unBinary <$> fromField f dat
314 else doFromField f okText' pure dat
395 else doFromField f okText' pure dat
317instance FromField PQ.Oid where
398instance FromField PQ.Oid where
318− fromField f dat = PQ.Oid <$> atto (== $(inlineTypoid TI.oid)) decimal f dat
399+ fromField f dat = PQ.Oid <$> attoFieldParser (== TI.oidOid) decimal f dat
320-- | bytea, name, text, \"char\", bpchar, varchar, unknown
401-- | bytea, name, text, \"char\", bpchar, varchar, unknown
321instance FromField LB.ByteString where
402instance FromField LB.ByteString where
@@ -323,7 +404,7 @@ instance FromField LB.ByteString where
324unescapeBytea :: Field -> SB.ByteString
405unescapeBytea :: Field -> SB.ByteString
325 -> Conversion (Binary SB.ByteString)
406 -> Conversion (Binary SB.ByteString)
326−unescapeBytea f str = case unsafeDupablePerformIO (PQ.unescapeBytea str) of
407+unescapeBytea f str' = case unsafeDupablePerformIO (PQ.unescapeBytea str') of
327 Nothing -> returnError ConversionFailed f "unescapeBytea failed"
408 Nothing -> returnError ConversionFailed f "unescapeBytea failed"
328 Just str -> pure (Binary str)
409 Just str -> pure (Binary str)
@@ -346,54 +427,85 @@ instance FromField ST.Text where
346instance FromField LT.Text where
427instance FromField LT.Text where
347 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)
349-- | name, text, \"char\", bpchar, varchar
452-- | name, text, \"char\", bpchar, varchar
350instance FromField [Char] where
453instance FromField [Char] where
351 fromField f dat = ST.unpack <$> fromField f dat
454 fromField f dat = ST.unpack <$> fromField f dat
353-- | timestamptz
456-- | timestamptz
354instance FromField UTCTime where
457instance FromField UTCTime where
355− fromField = ff $(inlineTypoid TI.timestamptz) "UTCTime" parseUTCTime
458+ fromField = ff TI.timestamptzOid "UTCTime" parseUTCTime
357-- | timestamptz
460-- | timestamptz
358instance FromField ZonedTime where
461instance FromField ZonedTime where
359− fromField = ff $(inlineTypoid TI.timestamptz) "ZonedTime" parseZonedTime
462+ fromField = ff TI.timestamptzOid "ZonedTime" parseZonedTime
361-- | timestamp
464-- | timestamp
362instance FromField LocalTime where
465instance FromField LocalTime where
363− fromField = ff $(inlineTypoid TI.timestamp) "LocalTime" parseLocalTime
466+ fromField = ff TI.timestampOid "LocalTime" parseLocalTime
366instance FromField Day where
469instance FromField Day where
367− fromField = ff $(inlineTypoid TI.date) "Day" parseDay
470+ fromField = ff TI.dateOid "Day" parseDay
370instance FromField TimeOfDay where
473instance FromField TimeOfDay where
371− fromField = ff $(inlineTypoid TI.time) "TimeOfDay" parseTimeOfDay
474+ fromField = ff TI.timeOid "TimeOfDay" parseTimeOfDay
373-- | timestamptz
476-- | timestamptz
374instance FromField UTCTimestamp where
477instance FromField UTCTimestamp where
375− fromField = ff $(inlineTypoid TI.timestamptz) "UTCTimestamp" parseUTCTimestamp
478+ fromField = ff TI.timestamptzOid "UTCTimestamp" parseUTCTimestamp
377-- | timestamptz
480-- | timestamptz
378instance FromField ZonedTimestamp where
481instance FromField ZonedTimestamp where
379− fromField = ff $(inlineTypoid TI.timestamptz) "ZonedTimestamp" parseZonedTimestamp
482+ fromField = ff TI.timestamptzOid "ZonedTimestamp" parseZonedTimestamp
381-- | timestamp
484-- | timestamp
382instance FromField LocalTimestamp where
485instance FromField LocalTimestamp where
383− fromField = ff $(inlineTypoid TI.timestamp) "LocalTimestamp" parseLocalTimestamp
486+ fromField = ff TI.timestampOid "LocalTimestamp" parseLocalTimestamp
386instance FromField Date where
489instance FromField Date where
387− fromField = ff $(inlineTypoid TI.date) "Date" parseDate
490+ fromField = ff TI.dateOid "Date" parseDate
492+-- | interval. Requires you to configure intervalstyle as @iso_8601@.
494+-- You can configure intervalstyle on every connection with a @SET@ command,
495+-- but for better performance you may want to configure it permanently in the
496+-- file found with @SHOW config_file;@ .
498+instance FromField CalendarDiffTime where
499+ fromField = ff TI.intervalOid "CalendarDiffTime" parseCalendarDiffTime
389ff :: PQ.Oid -> String -> (B8.ByteString -> Either String a)
501ff :: PQ.Oid -> String -> (B8.ByteString -> Either String a)
390 -> Field -> Maybe B8.ByteString -> Conversion a
502 -> Field -> Maybe B8.ByteString -> Conversion a
391−ff compatOid hsType parse f mstr =
503+ff compatOid hsType parseBS f mstr =
392 if typeOid f /= compatOid
504 if typeOid f /= compatOid
393 then err Incompatible ""
505 then err Incompatible ""
394 else case mstr of
506 else case mstr of
395 Nothing -> err UnexpectedNull ""
507 Nothing -> err UnexpectedNull ""
396− Just str -> case parse str of
508+ Just str -> case parseBS str of
397 Left msg -> err ConversionFailed msg
509 Left msg -> err ConversionFailed msg
398 Right val -> return val
510 Right val -> return val
@@ -414,33 +526,45 @@ instance (FromField a, FromField b) => FromField (Either a b) where
414 <|> (Left <$> fromField f dat)
526 <|> (Left <$> fromField f dat)
416-- | any postgresql array whose elements are compatible with type @a@
528-- | any postgresql array whose elements are compatible with type @a@
417−instance (FromField a, Typeable a) => FromField (Vector a) where
529+instance (FromField a, Typeable a) => FromField (PGArray a) where
418− fromField f mdat = do
530+ fromField = pgArrayFieldParser fromField
532+pgArrayFieldParser :: Typeable a => FieldParser a -> FieldParser (PGArray a)
533+pgArrayFieldParser fieldParser f mdat = do
419 info <- typeInfo f
534 info <- typeInfo f
420 case info of
535 case info of
421 TI.Array{} ->
536 TI.Array{} ->
422 case mdat of
537 case mdat of
423 Nothing -> returnError UnexpectedNull f ""
538 Nothing -> returnError UnexpectedNull f ""
424 Just dat -> do
539 Just dat -> do
425− case parseOnly (fromArray info f) dat of
540+ case parseOnly (fromArray fieldParser info f) dat of
426 Left err -> returnError ConversionFailed f err
541 Left err -> returnError ConversionFailed f err
427− Right conv -> V.fromList <$> conv
542+ Right conv -> PGArray <$> conv
428 _ -> returnError Incompatible f ""
543 _ -> returnError Incompatible f ""
430−fromArray :: (FromField a)
431− => TypeInfo -> Field -> Parser (Conversion [a])
545+fromArray :: FieldParser a -> TypeInfo -> Field -> Parser (Conversion [a])
432−fromArray typeInfo f = sequence . (parseIt <$>) <$> array delim
546+fromArray fieldParser typInfo f = sequence . (parseIt <$>) <$> array delim
434− delim = typdelim (typelem typeInfo)
548+ delim = typdelim (typelem typInfo)
435− fElem = f{ typeOid = typoid (typelem typeInfo) }
549+ fElem = f{ typeOid = typoid (typelem typInfo) }
436− 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
437− where f' | Arrays.Array _ <- item = f
555+ f' | Arrays.Array _ <- item = f
438− | otherwise = fElem
556+ | otherwise = fElem
558+instance (FromField a, Typeable a) => FromField (Vector a) where
559+ fromField f v = V.fromList . fromPGArray <$> fromField f v
561+instance (FromField a, Typeable a) => FromField (IOVector a) where
562+ fromField f v = liftConversion . V.unsafeThaw =<< fromField f v
441instance FromField UUID where
565instance FromField UUID where
442 fromField f mbs =
566 fromField f mbs =
443− if typeOid f /= $(inlineTypoid TI.uuid)
567+ if typeOid f /= TI.uuidOid
444 then returnError Incompatible f ""
568 then returnError Incompatible f ""
445 else case mbs of
569 else case mbs of
446 Nothing -> returnError UnexpectedNull f ""
570 Nothing -> returnError UnexpectedNull f ""
@@ -449,20 +573,26 @@ instance FromField UUID where
449 Nothing -> returnError ConversionFailed f "Invalid UUID"
573 Nothing -> returnError ConversionFailed f "Invalid UUID"
450 Just uuid -> pure uuid
574 Just uuid -> pure uuid
452−-- | json
576+-- | json, jsonb
453instance FromField JSON.Value where
577instance FromField JSON.Value where
454− fromField f mbs =
578+ fromField f mbs = parseBS =<< fromFieldJSONByteString f mbs
455− 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
456 then returnError Incompatible f ""
589 then returnError Incompatible f ""
457 else case mbs of
590 else case mbs of
458 Nothing -> returnError UnexpectedNull f ""
591 Nothing -> returnError UnexpectedNull f ""
459− Just bs ->
592+ Just bs -> pure bs
460− case JSON.eitherDecodeStrict' bs of
461− Left err -> returnError ConversionFailed f err
462− Right val -> pure val
464-- | 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
465−-- Haskell value using 'JSON.fromJSON'.
595+-- Haskell value using the 'JSON.FromJSON' instance.
467-- This can be used as the default implementation for the 'fromField'
597-- This can be used as the default implementation for the 'fromField'
468-- method for Haskell types that have a JSON representation in
598-- method for Haskell types that have a JSON representation in
@@ -470,14 +600,23 @@ instance FromField JSON.Value where
471-- The 'Typeable' constraint is required to show more informative
601-- The 'Typeable' constraint is required to show more informative
472-- 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@
473fromJSONField :: (JSON.FromJSON a, Typeable a) => FieldParser a
613fromJSONField :: (JSON.FromJSON a, Typeable a) => FieldParser a
474fromJSONField f mbBs = do
614fromJSONField f mbBs = do
475 value <- fromField f mbBs
615 value <- fromField f mbBs
476− case JSON.fromJSON value of
616+ case JSON.ifromJSON value of
477− JSON.Error err -> returnError ConversionFailed f $
617+ JSON.IError path err -> returnError ConversionFailed f $
478− "JSON decoding error: " ++ err
618+ "JSON decoding error: " ++ (JSON.formatError path err)
479− JSON.Success x -> pure x
619+ JSON.ISuccess x -> pure x
482-- | Compatible with the same set of types as @a@. Note that
621-- | Compatible with the same set of types as @a@. Note that
483-- modifying the 'IORef' does not have any effects outside
622-- modifying the 'IORef' does not have any effects outside
@@ -494,20 +633,33 @@ instance FromField a => FromField (MVar a) where
494type Compat = PQ.Oid -> Bool
633type Compat = PQ.Oid -> Bool
496okText, okText', okBinary, ok16, ok32, ok64, okInt :: Compat
635okText, okText', okBinary, ok16, ok32, ok64, okInt :: Compat
497−okText = $( mkCompats [ TI.name, TI.text, TI.char,
636+okText = eq TI.nameOid \/ eq TI.textOid \/ eq TI.charOid
498− TI.bpchar, TI.varchar ] )
637+ \/ eq TI.bpcharOid \/ eq TI.varcharOid
499−okText' = $( mkCompats [ TI.name, TI.text, TI.char,
638+okText' = eq TI.nameOid \/ eq TI.textOid \/ eq TI.charOid
500− TI.bpchar, TI.varchar, TI.unknown ] )
639+ \/ eq TI.bpcharOid \/ eq TI.varcharOid \/ eq TI.unknownOid
501−okBinary = (== $( inlineTypoid TI.bytea ))
640+okBinary = eq TI.byteaOid
502−ok16 = (== $( inlineTypoid TI.int2 ))
641+ok16 = eq TI.int2Oid
503−ok32 = $( mkCompats [TI.int2,TI.int4] )
642+ok32 = eq TI.int2Oid \/ eq TI.int4Oid
504−ok64 = $( mkCompats [TI.int2,TI.int4,TI.int8] )
643+ok64 = eq TI.int2Oid \/ eq TI.int4Oid \/ eq TI.int8Oid
505#if WORD_SIZE_IN_BITS < 64
644#if WORD_SIZE_IN_BITS < 64
506okInt = ok32
645okInt = ok32
508okInt = 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
511doFromField :: forall a . (Typeable a)
663doFromField :: forall a . (Typeable a)
512 => Field -> Compat -> (ByteString -> Conversion a)
664 => Field -> Compat -> (ByteString -> Conversion a)
513 -> Maybe ByteString -> Conversion a
665 -> Maybe ByteString -> Conversion a
@@ -532,10 +684,22 @@ returnError mkErr f msg = do
532 (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)
535−atto :: forall a. (Typeable a)
696+attoFieldParser :: forall a. (Typeable a)
536− => Compat -> Parser a -> Field -> Maybe ByteString
697+ => (PQ.Oid -> Bool)
537− -> Conversion a
698+ -- ^ Predicate for whether the postgresql type oid is compatible with this parser
700+ -- ^ An attoparsec parser.
538−atto types p0 f dat = doFromField f types (go p0) dat
702+attoFieldParser types p0 f dat = doFromField f types (go p0) dat
540 go :: Parser a -> ByteString -> Conversion a
704 go :: Parser a -> ByteString -> Conversion a