@@ -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' '<$>' 'Database.PostgreSQL.Simple.FromRow.field'@, although
34+this idiom is additionally compatible with PostgreSQL's @int8@ and @numeric@
35+types. If this is unacceptable, you may find
36+'Database.PostgreSQL.Simple.FromRow.fieldWith' useful.
38+Also note that while converting to a 'Double' through the 'Scientific' type
39+is likely somewhat faster than converting through the 'Rational' type,
40+the 'Scientific' type has no way to represent @NaN@ and @±Infinity@ values.
41+Thus, if you need precision conversion of regular floating point values
42+and the possibility of receiving these special values from the backend,
43+stick with 'Rational'.
26Because 'FromField' is a typeclass, one may provide conversions to
45Because 'FromField' is a typeclass, one may provide conversions to
27additional Haskell types without modifying postgresql-simple. This is
46additional Haskell types without modifying postgresql-simple. This is
28particularly useful for supporting PostgreSQL types that postgresql-simple
47particularly useful for supporting PostgreSQL types that postgresql-simple
@@ -87,32 +106,38 @@ module Database.PostgreSQL.Simple.FromField
87 , typeOid
106 , typeOid
88 , PQ.Oid(..)
107 , PQ.Oid(..)
89 , PQ.Format(..)
108 , PQ.Format(..)
109+ , pgArrayFieldParser
91 , fromJSONField
113 , fromJSONField
114+ , fromFieldJSONByteString
94#include "MachDeps.h"
117#include "MachDeps.h"
96−import Control.Applicative
119+import Control.Applicative ( Const(Const), (<|>), (<$>), pure, (*>), (<*) )
97− ( Applicative, (<|>), (<$>), pure )
120+import Control.Concurrent.MVar (MVar, newMVar)
98−import Control.Exception (Exception)
121+import Control.Exception (Exception (toException, fromException))
99import qualified Data.Aeson as JSON
122import qualified Data.Aeson as JSON
100−import Data.Attoparsec.Char8 hiding (Result)
123+import Data.Attoparsec.ByteString.Char8 hiding (Result)
101import Data.ByteString (ByteString)
124import Data.ByteString (ByteString)
102import qualified Data.ByteString.Char8 as B
125import qualified Data.ByteString.Char8 as B
126+import Data.Functor.Identity (Identity(Identity))
103import Data.Int (Int16, Int32, Int64)
127import Data.Int (Int16, Int32, Int64)
128+import Data.IORef (IORef, newIORef)
104import Data.Ratio (Ratio)
129import Data.Ratio (Ratio)
105−import Data.Time ( UTCTime, ZonedTime, LocalTime, Day, TimeOfDay )
130+import Data.Time.Compat ( UTCTime, ZonedTime, LocalTime, Day, TimeOfDay, CalendarDiffTime )
106import Data.Typeable (Typeable, typeOf)
131import Data.Typeable (Typeable, typeOf)
107import Data.Vector (Vector)
132import Data.Vector (Vector)
133+import Data.Vector.Mutable (IOVector)
108import qualified Data.Vector as V
134import qualified Data.Vector as V
109import Database.PostgreSQL.Simple.Internal
135import Database.PostgreSQL.Simple.Internal
110import Database.PostgreSQL.Simple.Compat
136import Database.PostgreSQL.Simple.Compat
111import Database.PostgreSQL.Simple.Ok
137import Database.PostgreSQL.Simple.Ok
112−import Database.PostgreSQL.Simple.Types (Binary(..), Null(..))
138+import Database.PostgreSQL.Simple.Types
113import Database.PostgreSQL.Simple.TypeInfo as TI
139import Database.PostgreSQL.Simple.TypeInfo as TI
114import qualified Database.PostgreSQL.Simple.TypeInfo.Static as TI
140import qualified Database.PostgreSQL.Simple.TypeInfo.Static as TI
115−import Database.PostgreSQL.Simple.TypeInfo.Macro as TI
116import Database.PostgreSQL.Simple.Time
141import Database.PostgreSQL.Simple.Time
117import Database.PostgreSQL.Simple.Arrays as Arrays
142import Database.PostgreSQL.Simple.Arrays as Arrays
118import qualified Database.PostgreSQL.LibPQ as PQ
143import qualified Database.PostgreSQL.LibPQ as PQ
@@ -122,8 +147,14 @@ import qualified Data.ByteString.Lazy as LB
122import qualified Data.Text as ST
147import qualified Data.Text as ST
123import qualified Data.Text.Encoding as ST
148import qualified Data.Text.Encoding as ST
124import qualified Data.Text.Lazy as LT
149import qualified Data.Text.Lazy as LT
125−import Data.UUID (UUID)
150+import Data.CaseInsensitive (CI)
151+import qualified Data.CaseInsensitive as CI
152+import Data.UUID.Types (UUID)
126−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
128-- | Exception thrown if conversion from a SQL value to a Haskell
159-- | Exception thrown if conversion from a SQL value to a Haskell
129-- value fails.
160-- value fails.
@@ -151,7 +182,9 @@ data ResultError = Incompatible { errSQLType :: String
151 -- between metadata and actual data in a row).
182 -- between metadata and actual data in a row).
152 deriving (Eq, Show, Typeable)
183 deriving (Eq, Show, Typeable)
154−instance Exception ResultError
185+instance Exception ResultError where
186+ toException = postgresqlExceptionToException
187+ fromException = postgresqlExceptionFromException
156left :: Exception a => a -> Conversion b
189left :: Exception a => a -> Conversion b
157left = conversionError
190left = conversionError
@@ -166,6 +199,16 @@ class FromField a where
166 -- 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
167 -- library instances, this will usually be a single 'ResultError', but
200 -- library instances, this will usually be a single 'ResultError', but
168 -- 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.
170-- | 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
171-- 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
@@ -182,7 +225,7 @@ typename field = typname <$> typeInfo field
183typeInfo :: Field -> Conversion TypeInfo
226typeInfo :: Field -> Conversion TypeInfo
184typeInfo Field{..} = Conversion $ \conn -> do
227typeInfo Field{..} = Conversion $ \conn -> do
185− Ok <$> (getTypeInfo conn =<< PQ.ftype result column)
228+ Ok <$> (getTypeInfo conn typeOid)
187typeInfoByOid :: PQ.Oid -> Conversion TypeInfo
230typeInfoByOid :: PQ.Oid -> Conversion TypeInfo
188typeInfoByOid oid = Conversion $ \conn -> do
231typeInfoByOid oid = Conversion $ \conn -> do
@@ -207,9 +250,11 @@ tableOid Field{..} = toMaybeOid (unsafeDupablePerformIO (PQ.ftable result column
207 then Nothing
250 then Nothing
208 else Just x
251 else Just x
210−-- | 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
211−-- 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
212−-- to libpq's @PQftablecol@.
257+-- protocol. Analogous to libpq's @PQftablecol@.
214tableColumn :: Field -> Int
259tableColumn :: Field -> Int
215tableColumn Field{..} = fromCol (unsafeDupablePerformIO (PQ.ftablecol result column))
260tableColumn Field{..} = fromCol (unsafeDupablePerformIO (PQ.ftablecol result column))
@@ -225,16 +270,33 @@ format Field{..} = unsafeDupablePerformIO (PQ.fformat result column)
226instance FromField () where
271instance FromField () where
227 fromField f _bs
272 fromField f _bs
228− | typeOid f /= $(inlineTypoid TI.void) = returnError Incompatible f ""
273+ | typeOid f /= TI.voidOid = returnError Incompatible f ""
229 | otherwise = pure ()
274 | otherwise = pure ()
276+instance (FromField a) => FromField (Const a b) where
277+ fromField f bs = Const <$> fromField f bs
279+instance (FromField a) => FromField (Identity a) where
280+ fromField f bs = Identity <$> fromField f bs
231-- | For dealing with null values. Compatible with any postgresql type
282-- | For dealing with null values. Compatible with any postgresql type
232-- compatible with type @a@. Note that the type is not checked if
283-- compatible with type @a@. Note that the type is not checked if
233-- the value is null, although it is inadvisable to rely on this
284-- the value is null, although it is inadvisable to rely on this
234-- behavior.
285-- behavior.
235−instance (FromField a) => FromField (Maybe a) where
286+instance FromField a => FromField (Maybe a) where
287+ fromField = optionalField fromField
289+-- | For dealing with SQL @null@ values outside of the 'FromField' class.
290+-- Alternatively, one could use 'Control.Applicative.optional', but that
291+-- also turns type and conversion errors into 'Nothing', whereas this is
292+-- more specific and turns only @null@ values into 'Nothing'.
294+optionalField :: FieldParser a -> FieldParser (Maybe a)
295+optionalField p f mv =
236− fromField _ Nothing = pure Nothing
297+ Nothing -> pure Nothing
237− fromField f bs = Just <$> fromField f bs
298+ Just _ -> Just <$> p f mv
299+{-# INLINE optionalField #-}
239-- | compatible with any data type, but the value must be null
301-- | compatible with any data type, but the value must be null
240instance FromField Null where
302instance FromField Null where
@@ -244,30 +306,30 @@ instance FromField Null where
245instance FromField Bool where
307instance FromField Bool where
246 fromField f bs
308 fromField f bs
247− | typeOid f /= $(inlineTypoid TI.bool) = returnError Incompatible f ""
309+ | typeOid f /= TI.boolOid = returnError Incompatible f ""
248 | bs == Nothing = returnError UnexpectedNull f ""
310 | bs == Nothing = returnError UnexpectedNull f ""
249 | bs == Just "t" = pure True
311 | bs == Just "t" = pure True
250 | bs == Just "f" = pure False
312 | bs == Just "f" = pure False
251 | otherwise = returnError ConversionFailed f ""
313 | otherwise = returnError ConversionFailed f ""
253−-- | \"char\"
315+-- | \"char\", bpchar
254instance FromField Char where
316instance FromField Char where
255− fromField f bs =
317+ fromField f bs0 =
256− if typeOid f /= $(inlineTypoid TI.char)
318+ if (eq TI.charOid \/ eq TI.bpcharOid) (typeOid f)
257− then returnError Incompatible f ""
258− else case bs of
319+ then case bs0 of
259 Nothing -> returnError UnexpectedNull f ""
320 Nothing -> returnError UnexpectedNull f ""
260 Just bs -> if B.length bs /= 1
321 Just bs -> if B.length bs /= 1
261 then returnError ConversionFailed f "length not 1"
322 then returnError ConversionFailed f "length not 1"
262 else return $! (B.head bs)
323 else return $! (B.head bs)
324+ else returnError Incompatible f ""
265instance FromField Int16 where
327instance FromField Int16 where
266− fromField = atto ok16 $ signed decimal
328+ fromField = attoFieldParser ok16 $ signed decimal
268-- | int2, int4
330-- | int2, int4
269instance FromField Int32 where
331instance FromField Int32 where
270− fromField = atto ok32 $ signed decimal
332+ fromField = attoFieldParser ok32 $ signed decimal
272#if WORD_SIZE_IN_BITS < 64
334#if WORD_SIZE_IN_BITS < 64
273-- | 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.
@@ -277,43 +339,64 @@ instance FromField Int32 where
277-- This library was compiled as 64-bit code.
339-- This library was compiled as 64-bit code.
279instance FromField Int where
341instance FromField Int where
280− fromField = atto okInt $ signed decimal
342+ fromField = attoFieldParser okInt $ signed decimal
282-- | int2, int4, int8
344-- | int2, int4, int8
283instance FromField Int64 where
345instance FromField Int64 where
284− fromField = atto ok64 $ signed decimal
346+ fromField = attoFieldParser ok64 $ signed decimal
286-- | int2, int4, int8
348-- | int2, int4, int8
287instance FromField Integer where
349instance FromField Integer where
288− fromField = atto ok64 $ signed decimal
350+ fromField = attoFieldParser ok64 $ signed decimal
290−-- | int2, float4
352+-- | int2, float4 (Uses attoparsec's 'double' routine, for
353+-- better accuracy convert to 'Scientific' or 'Rational' first)
291instance FromField Float where
354instance FromField Float where
292− fromField = atto ok (realToFrac <$> double)
355+ fromField = attoFieldParser ok (realToFrac <$> pg_double)
293− where ok = $(mkCompats [TI.float4,TI.int2])
356+ where ok = eq TI.float4Oid \/ eq TI.int2Oid
295−-- | int2, int4, float4, float8
358+-- | int2, int4, float4, float8 (Uses attoparsec's 'double' routine, for
359+-- better accuracy convert to 'Scientific' or 'Rational' first)
296instance FromField Double where
360instance FromField Double where
297− fromField = atto ok double
361+ fromField = attoFieldParser ok pg_double
298− 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
300−-- | int2, int4, float4, float8, numeric
364+-- | int2, int4, int8, float4, float8, numeric
301instance FromField (Ratio Integer) where
365instance FromField (Ratio Integer) where
302− fromField = atto ok rational
366+ fromField = attoFieldParser ok pg_rational
303− 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
305unBinary :: Binary t -> t
374unBinary :: Binary t -> t
306unBinary (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))
308-- | bytea, name, text, \"char\", bpchar, varchar, unknown
391-- | bytea, name, text, \"char\", bpchar, varchar, unknown
309instance FromField SB.ByteString where
392instance FromField SB.ByteString where
310− fromField f dat = if typeOid f == $(inlineTypoid TI.bytea)
393+ fromField f dat = if typeOid f == TI.byteaOid
311 then unBinary <$> fromField f dat
394 then unBinary <$> fromField f dat
312 else doFromField f okText' pure dat
395 else doFromField f okText' pure dat
315instance FromField PQ.Oid where
398instance FromField PQ.Oid where
316− fromField f dat = PQ.Oid <$> atto (== $(inlineTypoid TI.oid)) decimal f dat
399+ fromField f dat = PQ.Oid <$> attoFieldParser (== TI.oidOid) decimal f dat
318-- | bytea, name, text, \"char\", bpchar, varchar, unknown
401-- | bytea, name, text, \"char\", bpchar, varchar, unknown
319instance FromField LB.ByteString where
402instance FromField LB.ByteString where
@@ -321,7 +404,7 @@ instance FromField LB.ByteString where
322unescapeBytea :: Field -> SB.ByteString
405unescapeBytea :: Field -> SB.ByteString
323 -> Conversion (Binary SB.ByteString)
406 -> Conversion (Binary SB.ByteString)
324−unescapeBytea f str = case unsafeDupablePerformIO (PQ.unescapeBytea str) of
407+unescapeBytea f str' = case unsafeDupablePerformIO (PQ.unescapeBytea str') of
325 Nothing -> returnError ConversionFailed f "unescapeBytea failed"
408 Nothing -> returnError ConversionFailed f "unescapeBytea failed"
326 Just str -> pure (Binary str)
409 Just str -> pure (Binary str)
@@ -344,54 +427,85 @@ instance FromField ST.Text where
344instance FromField LT.Text where
427instance FromField LT.Text where
345 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)
347-- | name, text, \"char\", bpchar, varchar
452-- | name, text, \"char\", bpchar, varchar
348instance FromField [Char] where
453instance FromField [Char] where
349 fromField f dat = ST.unpack <$> fromField f dat
454 fromField f dat = ST.unpack <$> fromField f dat
351-- | timestamptz
456-- | timestamptz
352instance FromField UTCTime where
457instance FromField UTCTime where
353− fromField = ff $(inlineTypoid TI.timestamptz) "UTCTime" parseUTCTime
458+ fromField = ff TI.timestamptzOid "UTCTime" parseUTCTime
355-- | timestamptz
460-- | timestamptz
356instance FromField ZonedTime where
461instance FromField ZonedTime where
357− fromField = ff $(inlineTypoid TI.timestamptz) "ZonedTime" parseZonedTime
462+ fromField = ff TI.timestamptzOid "ZonedTime" parseZonedTime
359-- | timestamp
464-- | timestamp
360instance FromField LocalTime where
465instance FromField LocalTime where
361− fromField = ff $(inlineTypoid TI.timestamp) "LocalTime" parseLocalTime
466+ fromField = ff TI.timestampOid "LocalTime" parseLocalTime
364instance FromField Day where
469instance FromField Day where
365− fromField = ff $(inlineTypoid TI.date) "Day" parseDay
470+ fromField = ff TI.dateOid "Day" parseDay
368instance FromField TimeOfDay where
473instance FromField TimeOfDay where
369− fromField = ff $(inlineTypoid TI.time) "TimeOfDay" parseTimeOfDay
474+ fromField = ff TI.timeOid "TimeOfDay" parseTimeOfDay
371-- | timestamptz
476-- | timestamptz
372instance FromField UTCTimestamp where
477instance FromField UTCTimestamp where
373− fromField = ff $(inlineTypoid TI.timestamptz) "UTCTimestamp" parseUTCTimestamp
478+ fromField = ff TI.timestamptzOid "UTCTimestamp" parseUTCTimestamp
375-- | timestamptz
480-- | timestamptz
376instance FromField ZonedTimestamp where
481instance FromField ZonedTimestamp where
377− fromField = ff $(inlineTypoid TI.timestamptz) "ZonedTimestamp" parseZonedTimestamp
482+ fromField = ff TI.timestamptzOid "ZonedTimestamp" parseZonedTimestamp
379-- | timestamp
484-- | timestamp
380instance FromField LocalTimestamp where
485instance FromField LocalTimestamp where
381− fromField = ff $(inlineTypoid TI.timestamp) "LocalTimestamp" parseLocalTimestamp
486+ fromField = ff TI.timestampOid "LocalTimestamp" parseLocalTimestamp
384instance FromField Date where
489instance FromField Date where
385− fromField = ff $(inlineTypoid TI.date) "Date" parseDate
490+ fromField = ff TI.dateOid "Date" parseDate
492+-- | interval. Requires you to configure intervalstyle as @iso_8601@.
494+-- You can configure intervalstyle on every connection with a @SET@ command,
495+-- but for better performance you may want to configure it permanently in the
496+-- file found with @SHOW config_file;@ .
498+instance FromField CalendarDiffTime where
499+ fromField = ff TI.intervalOid "CalendarDiffTime" parseCalendarDiffTime
387ff :: PQ.Oid -> String -> (B8.ByteString -> Either String a)
501ff :: PQ.Oid -> String -> (B8.ByteString -> Either String a)
388 -> Field -> Maybe B8.ByteString -> Conversion a
502 -> Field -> Maybe B8.ByteString -> Conversion a
389−ff compatOid hsType parse f mstr =
503+ff compatOid hsType parseBS f mstr =
390 if typeOid f /= compatOid
504 if typeOid f /= compatOid
391 then err Incompatible ""
505 then err Incompatible ""
392 else case mstr of
506 else case mstr of
393 Nothing -> err UnexpectedNull ""
507 Nothing -> err UnexpectedNull ""
394− Just str -> case parse str of
508+ Just str -> case parseBS str of
395 Left msg -> err ConversionFailed msg
509 Left msg -> err ConversionFailed msg
396 Right val -> return val
510 Right val -> return val
@@ -412,33 +526,45 @@ instance (FromField a, FromField b) => FromField (Either a b) where
412 <|> (Left <$> fromField f dat)
526 <|> (Left <$> fromField f dat)
414-- | any postgresql array whose elements are compatible with type @a@
528-- | any postgresql array whose elements are compatible with type @a@
415−instance (FromField a, Typeable a) => FromField (Vector a) where
529+instance (FromField a, Typeable a) => FromField (PGArray a) where
416− fromField f mdat = do
530+ fromField = pgArrayFieldParser fromField
532+pgArrayFieldParser :: Typeable a => FieldParser a -> FieldParser (PGArray a)
533+pgArrayFieldParser fieldParser f mdat = do
417 info <- typeInfo f
534 info <- typeInfo f
418 case info of
535 case info of
419 TI.Array{} ->
536 TI.Array{} ->
420 case mdat of
537 case mdat of
421 Nothing -> returnError UnexpectedNull f ""
538 Nothing -> returnError UnexpectedNull f ""
422 Just dat -> do
539 Just dat -> do
423− case parseOnly (fromArray info f) dat of
540+ case parseOnly (fromArray fieldParser info f) dat of
424 Left err -> returnError ConversionFailed f err
541 Left err -> returnError ConversionFailed f err
425− Right conv -> V.fromList <$> conv
542+ Right conv -> PGArray <$> conv
426 _ -> returnError Incompatible f ""
543 _ -> returnError Incompatible f ""
428−fromArray :: (FromField a)
429− => TypeInfo -> Field -> Parser (Conversion [a])
545+fromArray :: FieldParser a -> TypeInfo -> Field -> Parser (Conversion [a])
430−fromArray typeInfo f = sequence . (parseIt <$>) <$> array delim
546+fromArray fieldParser typInfo f = sequence . (parseIt <$>) <$> array delim
432− delim = typdelim (typelem typeInfo)
548+ delim = typdelim (typelem typInfo)
433− fElem = f{ typeOid = typoid (typelem typeInfo) }
549+ fElem = f{ typeOid = typoid (typelem typInfo) }
434− 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
435− where f' | Arrays.Array _ <- item = f
555+ f' | Arrays.Array _ <- item = f
436− | 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
439instance FromField UUID where
565instance FromField UUID where
440 fromField f mbs =
566 fromField f mbs =
441− if typeOid f /= $(inlineTypoid TI.uuid)
567+ if typeOid f /= TI.uuidOid
442 then returnError Incompatible f ""
568 then returnError Incompatible f ""
443 else case mbs of
569 else case mbs of
444 Nothing -> returnError UnexpectedNull f ""
570 Nothing -> returnError UnexpectedNull f ""
@@ -447,20 +573,26 @@ instance FromField UUID where
447 Nothing -> returnError ConversionFailed f "Invalid UUID"
573 Nothing -> returnError ConversionFailed f "Invalid UUID"
448 Just uuid -> pure uuid
574 Just uuid -> pure uuid
450−-- | json
576+-- | json, jsonb
451instance FromField JSON.Value where
577instance FromField JSON.Value where
452− fromField f mbs =
578+ fromField f mbs = parseBS =<< fromFieldJSONByteString f mbs
453− 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
454 then returnError Incompatible f ""
589 then returnError Incompatible f ""
455 else case mbs of
590 else case mbs of
456 Nothing -> returnError UnexpectedNull f ""
591 Nothing -> returnError UnexpectedNull f ""
457− Just bs ->
592+ Just bs -> pure bs
458− case JSON.eitherDecodeStrict' bs of
459− Left err -> returnError ConversionFailed f err
460− Right val -> pure val
462-- | 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
463−-- Haskell value using 'JSON.fromJSON'.
595+-- Haskell value using the 'JSON.FromJSON' instance.
465-- This can be used as the default implementation for the 'fromField'
597-- This can be used as the default implementation for the 'fromField'
466-- method for Haskell types that have a JSON representation in
598-- method for Haskell types that have a JSON representation in
@@ -468,31 +600,66 @@ instance FromField JSON.Value where
469-- The 'Typeable' constraint is required to show more informative
601-- The 'Typeable' constraint is required to show more informative
470-- 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@
471fromJSONField :: (JSON.FromJSON a, Typeable a) => FieldParser a
613fromJSONField :: (JSON.FromJSON a, Typeable a) => FieldParser a
472fromJSONField f mbBs = do
614fromJSONField f mbBs = do
473 value <- fromField f mbBs
615 value <- fromField f mbBs
474− case JSON.fromJSON value of
616+ case JSON.ifromJSON value of
475− JSON.Error err -> returnError ConversionFailed f $
617+ JSON.IError path err -> returnError ConversionFailed f $
476− "JSON decoding error: " ++ err
618+ "JSON decoding error: " ++ (JSON.formatError path err)
477− JSON.Success x -> pure x
619+ JSON.ISuccess x -> pure x
621+-- | Compatible with the same set of types as @a@. Note that
622+-- modifying the 'IORef' does not have any effects outside
623+-- the local process on the local machine.
624+instance FromField a => FromField (IORef a) where
625+ fromField f v = liftConversion . newIORef =<< fromField f v
627+-- | Compatible with the same set of types as @a@. Note that
628+-- modifying the 'MVar' does not have any effects outside
629+-- the local process on the local machine.
630+instance FromField a => FromField (MVar a) where
631+ fromField f v = liftConversion . newMVar =<< fromField f v
479type Compat = PQ.Oid -> Bool
633type Compat = PQ.Oid -> Bool
481okText, okText', okBinary, ok16, ok32, ok64, okInt :: Compat
635okText, okText', okBinary, ok16, ok32, ok64, okInt :: Compat
482−okText = $( mkCompats [ TI.name, TI.text, TI.char,
636+okText = eq TI.nameOid \/ eq TI.textOid \/ eq TI.charOid
483− TI.bpchar, TI.varchar ] )
637+ \/ eq TI.bpcharOid \/ eq TI.varcharOid
484−okText' = $( mkCompats [ TI.name, TI.text, TI.char,
638+okText' = eq TI.nameOid \/ eq TI.textOid \/ eq TI.charOid
485− TI.bpchar, TI.varchar, TI.unknown ] )
639+ \/ eq TI.bpcharOid \/ eq TI.varcharOid \/ eq TI.unknownOid
486−okBinary = (== $( inlineTypoid TI.bytea ))
640+okBinary = eq TI.byteaOid
487−ok16 = (== $( inlineTypoid TI.int2 ))
641+ok16 = eq TI.int2Oid
488−ok32 = $( mkCompats [TI.int2,TI.int4] )
642+ok32 = eq TI.int2Oid \/ eq TI.int4Oid
489−ok64 = $( mkCompats [TI.int2,TI.int4,TI.int8] )
643+ok64 = eq TI.int2Oid \/ eq TI.int4Oid \/ eq TI.int8Oid
490#if WORD_SIZE_IN_BITS < 64
644#if WORD_SIZE_IN_BITS < 64
491okInt = ok32
645okInt = ok32
493okInt = 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
496doFromField :: forall a . (Typeable a)
663doFromField :: forall a . (Typeable a)
497 => Field -> Compat -> (ByteString -> Conversion a)
664 => Field -> Compat -> (ByteString -> Conversion a)
498 -> Maybe ByteString -> Conversion a
665 -> Maybe ByteString -> Conversion a
@@ -517,10 +684,22 @@ returnError mkErr f msg = do
517 (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)
520−atto :: forall a. (Typeable a)
696+attoFieldParser :: forall a. (Typeable a)
521− => Compat -> Parser a -> Field -> Maybe ByteString
697+ => (PQ.Oid -> Bool)
522− -> Conversion a
698+ -- ^ Predicate for whether the postgresql type oid is compatible with this parser
700+ -- ^ An attoparsec parser.
523−atto types p0 f dat = doFromField f types (go p0) dat
702+attoFieldParser types p0 f dat = doFromField f types (go p0) dat
525 go :: Parser a -> ByteString -> Conversion a
704 go :: Parser a -> ByteString -> Conversion a