diff options
Diffstat (limited to 'users/Profpatsch/my-prelude/src')
| -rw-r--r-- | users/Profpatsch/my-prelude/src/MyPrelude.hs | 288 | ||||
| -rw-r--r-- | users/Profpatsch/my-prelude/src/Postgres/MonadPostgres.hs | 313 |
2 files changed, 480 insertions, 121 deletions
diff --git a/users/Profpatsch/my-prelude/src/MyPrelude.hs b/users/Profpatsch/my-prelude/src/MyPrelude.hs index 7857ace61fdb..cd246d172881 100644 --- a/users/Profpatsch/my-prelude/src/MyPrelude.hs +++ b/users/Profpatsch/my-prelude/src/MyPrelude.hs @@ -1,11 +1,7 @@ {-# LANGUAGE ImplicitParams #-} {-# LANGUAGE LambdaCase #-} {-# LANGUAGE MagicHash #-} -{-# LANGUAGE OverloadedStrings #-} -{-# LANGUAGE PolyKinds #-} -{-# LANGUAGE RankNTypes #-} -{-# LANGUAGE ScopedTypeVariables #-} -{-# OPTIONS_GHC -fexpose-all-unfoldings #-} +{-# LANGUAGE ViewPatterns #-} module MyPrelude ( -- * Text conversions @@ -15,6 +11,7 @@ module MyPrelude fmt, textToString, stringToText, + stringToBytesUtf8, showToText, textToBytesUtf8, textToBytesUtf8Lazy, @@ -42,6 +39,7 @@ module MyPrelude HasField, -- * Control flow + doAs, (&), (<&>), (<|>), @@ -91,6 +89,9 @@ module MyPrelude failure, successes, failures, + traverseValidate, + traverseValidateM, + traverseValidateM_, eitherToValidation, eitherToListValidation, validationToEither, @@ -100,15 +101,28 @@ module MyPrelude validationToThese, thenThese, thenValidate, + thenValidateM, NonEmpty ((:|)), + pattern IsEmpty, + pattern IsNonEmpty, singleton, nonEmpty, nonEmptyDef, + overNonEmpty, + zipNonEmpty, + zipWithNonEmpty, + zip3NonEmpty, + zipWith3NonEmpty, + zip4NonEmpty, toList, - toNonEmptyDefault, + lengthNatural, maximum1, minimum1, + maximumBy1, + minimumBy1, + Vector, Generic, + Lift, Semigroup, sconcat, Monoid, @@ -120,6 +134,7 @@ module MyPrelude Identity (Identity, runIdentity), Natural, intToNatural, + Scientific, Contravariant, contramap, (>$<), @@ -132,10 +147,16 @@ module MyPrelude Category, (>>>), (&>>), + Any, -- * Enum definition inverseFunction, inverseMap, + enumerateAll, + + -- * Map helpers + mapFromListOn, + mapFromListOnMerge, -- * Error handling HasCallStack, @@ -145,6 +166,7 @@ where import Control.Applicative ((<|>)) import Control.Category (Category, (>>>)) +import Control.Foldl.NonEmpty qualified as Foldl1 import Control.Monad (guard, join, unless, when) import Control.Monad.Catch (MonadThrow (throwM)) import Control.Monad.Except @@ -164,13 +186,15 @@ import Data.Char qualified import Data.Coerce (Coercible, coerce) import Data.Data (Proxy (Proxy)) import Data.Error -import Data.Foldable (Foldable (foldMap', toList), fold, foldl', for_, traverse_) +import Data.Foldable (Foldable (foldMap', toList), fold, foldl', for_, sequenceA_, traverse_) import Data.Foldable qualified as Foldable import Data.Function ((&)) import Data.Functor ((<&>)) import Data.Functor.Contravariant (Contravariant (contramap), (>$<)) import Data.Functor.Identity (Identity (runIdentity)) +import Data.List (zip4) import Data.List.NonEmpty (NonEmpty ((:|)), nonEmpty) +import Data.List.NonEmpty qualified as NonEmpty import Data.Map.Strict ( Map, ) @@ -178,7 +202,8 @@ import Data.Map.Strict qualified as Map import Data.Maybe (fromMaybe, mapMaybe) import Data.Maybe qualified as Maybe import Data.Profunctor (Profunctor, dimap, lmap, rmap) -import Data.Semigroup (Max (Max, getMax), Min (Min, getMin), sconcat) +import Data.Scientific (Scientific) +import Data.Semigroup (sconcat) import Data.Semigroup.Foldable (Foldable1 (fold1), foldMap1) import Data.Semigroup.Traversable (Traversable1) import Data.Semigroupoid (Semigroupoid (o)) @@ -192,14 +217,17 @@ import Data.Text.Lazy qualified import Data.Text.Lazy.Encoding qualified import Data.These (These (That, These, This)) import Data.Traversable (for) +import Data.Vector (Vector) import Data.Void (Void, absurd) import Data.Word (Word8) import GHC.Exception (errorCallWithCallStackException) -import GHC.Exts (RuntimeRep, TYPE, raise#) +import GHC.Exts (Any, RuntimeRep, TYPE, raise#) import GHC.Generics (Generic) import GHC.Natural (Natural) import GHC.Records (HasField) import GHC.Stack (HasCallStack) +import GHC.Utils.Encoding qualified as GHC +import Language.Haskell.TH.Syntax (Lift) import PyF (fmt) import System.Exit qualified import System.IO qualified @@ -212,6 +240,21 @@ import Validation validationToEither, ) +-- | Mark a `do`-block with the type of the Monad/Applicativ it uses. +-- Only intended for reading ease and making code easier to understand, +-- especially do-blocks that use unconventional monads (like Maybe or List). +-- +-- Example: +-- +-- @ +-- doAs @Maybe $ do +-- a <- Just 'a' +-- b <- Just 'b' +-- pure (a, b) +-- @ +doAs :: forall m a. m a -> m a +doAs = id + -- | Forward-applying 'contramap', like '&'/'$' and '<&>'/'<$>' but for '>$<'. (>&<) :: (Contravariant f) => f b -> (a -> b) -> f a (>&<) = flip contramap @@ -222,10 +265,10 @@ infixl 5 >&< -- -- Specialized examples: -- --- @@ +-- @ -- for functions : (a -> b) -> (b -> c) -> (a -> c) -- for Folds: Fold a b -> Fold b c -> Fold a c --- @@ +-- @ (&>>) :: (Semigroupoid s) => s a b -> s b c -> s a c (&>>) = flip Data.Semigroupoid.o @@ -266,26 +309,51 @@ bytesToTextUtf8LenientLazy :: Data.ByteString.Lazy.ByteString -> Data.Text.Lazy. bytesToTextUtf8LenientLazy = Data.Text.Lazy.Encoding.decodeUtf8With Data.Text.Encoding.Error.lenientDecode --- | Make a lazy text strict +-- | Make a lazy 'Text' strict. toStrict :: Data.Text.Lazy.Text -> Text toStrict = Data.Text.Lazy.toStrict --- | Make a strict text lazy +-- | Make a strict 'Text' lazy. toLazy :: Text -> Data.Text.Lazy.Text toLazy = Data.Text.Lazy.fromStrict +-- | Make a lazy 'ByteString' strict. toStrictBytes :: Data.ByteString.Lazy.ByteString -> ByteString toStrictBytes = Data.ByteString.Lazy.toStrict +-- | Make a strict 'ByteString' lazy. toLazyBytes :: ByteString -> Data.ByteString.Lazy.ByteString toLazyBytes = Data.ByteString.Lazy.fromStrict +-- | Convert a (performant) 'Text' into an (imperformant) list-of-char 'String'. +-- +-- Some libraries (like @time@ or @network-uri@) still use the `String` as their interface. We only want to convert to string at the edges, otherwise use 'Text'. +-- +-- ATTN: Don’t use `String` in code if you can avoid it, prefer `Text` instead. textToString :: Text -> String textToString = Data.Text.unpack +-- | Convert an (imperformant) list-of-char 'String' into a (performant) 'Text' . +-- +-- Some libraries (like @time@ or @network-uri@) still use the `String` as their interface. We want to convert 'String' to 'Text' as soon as possible and only use 'Text' in our code. +-- +-- ATTN: Don’t use `String` in code if you can avoid it, prefer `Text` instead. stringToText :: String -> Text stringToText = Data.Text.pack +-- | Encode a String to an UTF-8 encoded Bytestring +-- +-- ATTN: Don’t use `String` in code if you can avoid it, prefer `Text` instead. +stringToBytesUtf8 :: String -> ByteString +stringToBytesUtf8 = GHC.utf8EncodeString + +-- | Like `show`, but generate a 'Text' +-- +-- ATTN: This goes via `String` and thus is fairly inefficient. +-- We should add a good display library at one point. +-- +-- ATTN: unlike `show`, this forces the whole @'a +-- so only use if you want to display the whole thing. showToText :: (Show a) => a -> Text showToText = stringToText . show @@ -299,8 +367,20 @@ showToText = stringToText . show -- >>> charToWordUnsafe ',' -- 44 charToWordUnsafe :: Char -> Word8 -charToWordUnsafe = fromIntegral . Data.Char.ord {-# INLINE charToWordUnsafe #-} +charToWordUnsafe = fromIntegral . Data.Char.ord + +pattern IsEmpty :: [a] +pattern IsEmpty <- (null -> True) + where + IsEmpty = [] + +pattern IsNonEmpty :: NonEmpty a -> [a] +pattern IsNonEmpty n <- (nonEmpty -> Just n) + where + IsNonEmpty n = toList n + +{-# COMPLETE IsEmpty, IsNonEmpty #-} -- | Single element in a (non-empty) list. singleton :: a -> NonEmpty a @@ -313,19 +393,69 @@ nonEmptyDef def xs = Nothing -> def :| [] Just ne -> ne --- | Construct a non-empty list, given a default value if the ist list was empty. -toNonEmptyDefault :: a -> [a] -> NonEmpty a -toNonEmptyDefault def xs = case xs of - [] -> def :| [] - (x : xs') -> x :| xs' +-- | If the list is not empty, run the given function with a NonEmpty list, otherwise just return [] +overNonEmpty :: (Applicative f) => (NonEmpty a -> f [b]) -> [a] -> f [b] +overNonEmpty f xs = case xs of + IsEmpty -> pure [] + IsNonEmpty xs' -> f xs' + +-- | Zip two non-empty lists. +zipNonEmpty :: NonEmpty a -> NonEmpty b -> NonEmpty (a, b) +{-# INLINE zipNonEmpty #-} +zipNonEmpty ~(a :| as) ~(b :| bs) = (a, b) :| zip as bs + +-- | Zip two non-empty lists, combining them with the given function +zipWithNonEmpty :: (a -> b -> c) -> NonEmpty a -> NonEmpty b -> NonEmpty c +{-# INLINE zipWithNonEmpty #-} +zipWithNonEmpty = NonEmpty.zipWith + +-- | Zip three non-empty lists. +zip3NonEmpty :: NonEmpty a -> NonEmpty b -> NonEmpty c -> NonEmpty (a, b, c) +{-# INLINE zip3NonEmpty #-} +zip3NonEmpty ~(a :| as) ~(b :| bs) ~(c :| cs) = (a, b, c) :| zip3 as bs cs --- | @O(n)@. Get the maximum element from a non-empty structure. +-- | Zip three non-empty lists, combining them with the given function +zipWith3NonEmpty :: (a -> b -> c -> d) -> NonEmpty a -> NonEmpty b -> NonEmpty c -> NonEmpty d +{-# INLINE zipWith3NonEmpty #-} +zipWith3NonEmpty f ~(x :| xs) ~(y :| ys) ~(z :| zs) = f x y z :| zipWith3 f xs ys zs + +-- | Zip four non-empty lists +zip4NonEmpty :: NonEmpty a -> NonEmpty b -> NonEmpty c -> NonEmpty d -> NonEmpty (a, b, c, d) +{-# INLINE zip4NonEmpty #-} +zip4NonEmpty ~(a :| as) ~(b :| bs) ~(c :| cs) ~(d :| ds) = (a, b, c, d) :| zip4 as bs cs ds + +-- | We don’t want to use Foldable’s `length`, because it is too polymorphic and can lead to bugs. +-- Only list-y things should have a length. +class (Foldable f) => Lengthy f + +instance Lengthy [] + +instance Lengthy NonEmpty + +instance Lengthy Vector + +lengthNatural :: (Lengthy f) => f a -> Natural +lengthNatural xs = + xs + & Foldable.length + -- length can never be negative or something went really, really wrong + & fromIntegral @Int @Natural + +-- | @O(n)@. Get the maximum element from a non-empty structure (strict). maximum1 :: (Foldable1 f, Ord a) => f a -> a -maximum1 xs = xs & foldMap1 Max & getMax +maximum1 = Foldl1.fold1 Foldl1.maximum --- | @O(n)@. Get the minimum element from a non-empty structure. +-- | @O(n)@. Get the maximum element from a non-empty structure, using the given comparator (strict). +maximumBy1 :: (Foldable1 f) => (a -> a -> Ordering) -> f a -> a +maximumBy1 f = Foldl1.fold1 (Foldl1.maximumBy f) + +-- | @O(n)@. Get the minimum element from a non-empty structure (strict). minimum1 :: (Foldable1 f, Ord a) => f a -> a -minimum1 xs = xs & foldMap1 Min & getMin +minimum1 = Foldl1.fold1 Foldl1.minimum + +-- | @O(n)@. Get the minimum element from a non-empty structure, using the given comparator (strict). +minimumBy1 :: (Foldable1 f) => (a -> a -> Ordering) -> f a -> a +minimumBy1 f = Foldl1.fold1 (Foldl1.minimumBy f) -- | Annotate a 'Maybe' with an error message and turn it into an 'Either'. annotate :: err -> Maybe a -> Either err a @@ -355,8 +485,48 @@ findMaybe mPred list = Just a -> mPred a Nothing -> Nothing +-- | 'traverse' with a function returning 'Either' and collect all errors that happen, if they happen. +-- +-- Does not shortcut on error, so will always traverse the whole list/'Traversable' structure. +-- +-- This is a useful error handling function in many circumstances, +-- because it won’t only return the first error that happens, but rather all of them. +traverseValidate :: forall t a err b. (Traversable t) => (a -> Either err b) -> t a -> Either (NonEmpty err) (t b) +traverseValidate f as = + as + & traverse @t @(Validation _) (eitherToListValidation . f) + & validationToEither + +-- | 'traverse' with a function returning 'm Either' and collect all errors that happen, if they happen. +-- +-- Does not shortcut on error, so will always traverse the whole list/'Traversable' structure. +-- +-- This is a useful error handling function in many circumstances, +-- because it won’t only return the first error that happens, but rather all of them. +traverseValidateM :: forall t m a err b. (Traversable t, Applicative m) => (a -> m (Either err b)) -> t a -> m (Either (NonEmpty err) (t b)) +traverseValidateM f as = + as + & traverse @t @m (\a -> a & f <&> eitherToListValidation) + <&> sequenceA @t @(Validation _) + <&> validationToEither + +-- | 'traverse_' with a function returning 'm Either' and collect all errors that happen, if they happen. +-- +-- Does not shortcut on error, so will always traverse the whole list/'Traversable' structure. +-- +-- This is a useful error handling function in many circumstances, +-- because it won’t only return the first error that happens, but rather all of them. +traverseValidateM_ :: forall t m a err. (Traversable t, Applicative m) => (a -> m (Either err ())) -> t a -> m (Either (NonEmpty err) ()) +traverseValidateM_ f as = + as + & traverse @t @m (\a -> a & f <&> eitherToListValidation) + <&> sequenceA_ @t @(Validation _) + <&> validationToEither + -- | Like 'eitherToValidation', but puts the Error side into a NonEmpty list -- to make it combine with other validations. +-- +-- See also 'validateEithers', if you have a list of Either and want to collect all errors. eitherToListValidation :: Either a c -> Validation (NonEmpty a) c eitherToListValidation = first singleton . eitherToValidation @@ -388,15 +558,26 @@ thenThese f x = do th <- x join <$> traverse f th --- | Nested validating bind-like combinator inside some other @m@. +-- | Nested validating bind-like combinator. -- -- Use if you want to collect errors, and want to chain multiple functions returning 'Validation'. thenValidate :: + (a -> Validation err b) -> + Validation err a -> + Validation err b +thenValidate f = \case + Success a -> f a + Failure err -> Failure err + +-- | Nested validating bind-like combinator inside some other @m@. +-- +-- Use if you want to collect errors, and want to chain multiple functions returning 'Validation'. +thenValidateM :: (Monad m) => (a -> m (Validation err b)) -> m (Validation err a) -> m (Validation err b) -thenValidate f x = +thenValidateM f x = eitherToValidation <$> do x' <- validationToEither <$> x case x' of @@ -429,23 +610,23 @@ exitWithMessage msg = do -- -- … since @(Semigroup err => Validation err a)@ is a @Semigroup@/@Monoid@ itself. traverseFold :: (Applicative ap, Traversable t, Monoid m) => (a -> ap m) -> t a -> ap m +{-# INLINE traverseFold #-} traverseFold f xs = -- note: could be weakened to (Foldable t) via `getAp . foldMap (Ap . f)` fold <$> traverse f xs -{-# INLINE traverseFold #-} -- | Like 'traverseFold', but fold over a semigroup instead of a Monoid, by providing a starting element. traverseFoldDefault :: (Applicative ap, Traversable t, Semigroup m) => m -> (a -> ap m) -> t a -> ap m +{-# INLINE traverseFoldDefault #-} traverseFoldDefault def f xs = foldDef def <$> traverse f xs where foldDef = foldr (<>) -{-# INLINE traverseFoldDefault #-} -- | Same as 'traverseFold', but with a 'Semigroup' and 'Traversable1' restriction. traverseFold1 :: (Applicative ap, Traversable1 t, Semigroup s) => (a -> ap s) -> t a -> ap s +{-# INLINE traverseFold1 #-} -- note: cannot be weakened to (Foldable1 t) because there is no `Ap` for Semigroup (No `Apply` typeclass) traverseFold1 f xs = fold1 <$> traverse f xs -{-# INLINE traverseFold1 #-} -- | Use this in places where the code is still to be implemented. -- @@ -527,18 +708,31 @@ inverseFunction f k = Map.lookup k $ inverseMap f -- it returns a mapping from all possible outputs to their possible inputs. -- -- This has the same restrictions of 'inverseFunction'. -inverseMap :: - forall a k. - (Bounded a, Enum a, Ord k) => - (a -> k) -> - Map k a -inverseMap f = - universe - <&> (\a -> (f a, a)) - & Map.fromList - where - universe :: [a] - universe = [minBound .. maxBound] +inverseMap :: forall a k. (Bounded a, Enum a, Ord k) => (a -> k) -> Map k a +inverseMap f = enumerateAll <&> (\a -> (f a, a)) & Map.fromList + +-- | All possible values in this enum. +enumerateAll :: (Enum a, Bounded a) => [a] +enumerateAll = [minBound .. maxBound] + +-- | Create a 'Map' from a list of values, extracting the map key from each value. Like 'Map.fromList'. +-- +-- Attention: if the key is not unique, the earliest value with the key will be in the map. +mapFromListOn :: (Ord key) => (a -> key) -> [a] -> Map key a +mapFromListOn f xs = xs <&> (\x -> (f x, x)) & Map.fromList + +-- | Create a 'Map' from a list of values, merging multiple values at the same key with '<>' (left-to-right) +-- +-- `f` has to extract the key and value. Value must be mergable. +-- +-- Attention: if the key is not unique, the earliest value with the key will be in the map. +mapFromListOnMerge :: (Ord key, Semigroup s) => (a -> (key, s)) -> [a] -> Map key s +mapFromListOnMerge f xs = + xs + <&> (\x -> f x) + & Map.fromListWith + -- we have to flip (`<>`) because `Map.fromListWith` merges its values “the other way around” + (flip (<>)) -- | If the predicate is true, return the @m@, else 'mempty'. -- @@ -570,12 +764,18 @@ ifTrue pred' m = if pred' then m else mempty -- >>> import Data.Monoid (Sum(..)) -- -- >>> :{ mconcat [ --- unknown command '{' +-- ifExists (Just [1]), +-- [2, 3, 4], +-- ifExists Nothing, +-- ] +-- :} +-- [1,2,3,4] -- -- Or any other Monoid: -- --- >>> mconcat [ Sum 1, ifExists Sum (Just 2), Sum 3 ] +-- >>> mconcat [ Sum 1, ifExists (Just (Sum 2)), Sum 3 ] + -- Sum {getSum = 6} -ifExists :: (Monoid m) => (a -> m) -> Maybe a -> m -ifExists = foldMap +ifExists :: (Monoid m) => Maybe m -> m +ifExists = fold diff --git a/users/Profpatsch/my-prelude/src/Postgres/MonadPostgres.hs b/users/Profpatsch/my-prelude/src/Postgres/MonadPostgres.hs index 78e3897ef5f3..bd8ddd12f775 100644 --- a/users/Profpatsch/my-prelude/src/Postgres/MonadPostgres.hs +++ b/users/Profpatsch/my-prelude/src/Postgres/MonadPostgres.hs @@ -1,14 +1,15 @@ +{-# LANGUAGE AllowAmbiguousTypes #-} {-# LANGUAGE DeriveAnyClass #-} {-# LANGUAGE QuasiQuotes #-} -{-# LANGUAGE TemplateHaskell #-} {-# OPTIONS_GHC -Wno-orphans #-} module Postgres.MonadPostgres where import AtLeast (AtLeast) import Control.Exception +import Control.Foldl qualified as Fold import Control.Monad.Except -import Control.Monad.Logger (MonadLogger, logDebug, logWarn) +import Control.Monad.Logger.CallStack (MonadLogger, logDebug, logWarn) import Control.Monad.Reader (MonadReader (ask), ReaderT (..)) import Control.Monad.Trans.Resource import Data.Aeson (FromJSON) @@ -28,7 +29,7 @@ import Database.PostgreSQL.Simple.FromRow qualified as PG import Database.PostgreSQL.Simple.ToField (ToField) import Database.PostgreSQL.Simple.ToRow (ToRow (toRow)) import Database.PostgreSQL.Simple.Types (Query (..)) -import GHC.Records (HasField (..)) +import GHC.Records (getField) import Label import OpenTelemetry.Trace.Core qualified as Otel hiding (inSpan, inSpan') import OpenTelemetry.Trace.Monad qualified as Otel @@ -42,7 +43,7 @@ import Tool import UnliftIO (MonadUnliftIO (withRunInIO)) import UnliftIO.Process qualified as Process import UnliftIO.Resource qualified as Resource -import Prelude hiding (span) +import Prelude hiding (init, span) -- | Postgres queries/commands that can be executed within a running transaction. -- @@ -52,28 +53,46 @@ class (Monad m) => MonadPostgres (m :: Type -> Type) where -- | Execute an INSERT, UPDATE, or other SQL query that is not expected to return results. -- Returns the number of rows affected. - execute :: (ToRow params, Typeable params) => Query -> params -> Transaction m (Label "numberOfRowsAffected" Natural) - - -- | Execute an INSERT, UPDATE, or other SQL query that is not expected to return results. Does not take parameters. - - -- Returns the number of rows affected. - execute_ :: Query -> Transaction m (Label "numberOfRowsAffected" Natural) + execute :: + (ToRow params, Typeable params) => + Query -> + params -> + Transaction m (Label "numberOfRowsAffected" Natural) -- | Execute a multi-row INSERT, UPDATE, or other SQL query that is not expected to return results. -- - -- Returns the number of rows affected. If the list of parameters is empty, this function will simply return 0 without issuing the query to the backend. If this is not desired, consider using the 'PG.Values' constructor instead. - executeMany :: (ToRow params, Typeable params) => Query -> [params] -> Transaction m (Label "numberOfRowsAffected" Natural) - - -- | Execute INSERT ... RETURNING, UPDATE ... RETURNING, or other SQL query that accepts multi-row input and is expected to return results. Note that it is possible to write query conn "INSERT ... RETURNING ..." ... in cases where you are only inserting a single row, and do not need functionality analogous to 'executeMany'. + -- Returns the number of rows affected. If the list of parameters is empty, + -- this function will simply return 0 without issuing the query to the backend. + -- If this is not desired, consider using the 'PG.Values' constructor instead. + executeMany :: + (ToRow params, Typeable params) => + Query -> + NonEmpty params -> + Transaction m (Label "numberOfRowsAffected" Natural) + + -- | Execute INSERT ... RETURNING, UPDATE ... RETURNING, + -- or other SQL query that accepts multi-row input and is expected to return results. + -- Note that it is possible to write query conn "INSERT ... RETURNING ..." ... + -- in cases where you are only inserting a single row, + -- and do not need functionality analogous to 'executeMany'. -- -- If the list of parameters is empty, this function will simply return [] without issuing the query to the backend. If this is not desired, consider using the 'PG.Values' constructor instead. - executeManyReturningWith :: (ToRow q) => Query -> [q] -> Decoder r -> Transaction m [r] + executeManyReturningWith :: (ToRow q) => Query -> NonEmpty q -> Decoder r -> Transaction m [r] -- | Run a query, passing parameters and result row parser. - queryWith :: (PG.ToRow params, Typeable params, Typeable r) => PG.Query -> params -> Decoder r -> Transaction m [r] + queryWith :: + (PG.ToRow params, Typeable params, Typeable r) => + PG.Query -> + params -> + Decoder r -> + Transaction m [r] -- | Run a query without any parameters and result row parser. - queryWith_ :: (Typeable r) => PG.Query -> Decoder r -> Transaction m [r] + queryWith_ :: + (Typeable r) => + PG.Query -> + Decoder r -> + Transaction m [r] -- | Run a query, passing parameters, and fold over the resulting rows. -- @@ -82,13 +101,15 @@ class (Monad m) => MonadPostgres (m :: Type -> Type) where -- -- When dealing with small results, it may be simpler (and perhaps faster) to use query instead. -- - -- This fold is _not_ strict. The stream consumer is responsible for forcing the evaluation of its result to avoid space leaks. + -- This fold is _not_ strict. The stream consumer is responsible + -- for forcing the evaluation of its result to avoid space leaks. -- -- If you can, prefer aggregating in the database itself. - foldRows :: - (FromRow row, ToRow params, Typeable row, Typeable params) => + foldRowsWithAcc :: + (ToRow params, Typeable row, Typeable params) => Query -> params -> + Decoder row -> a -> (a -> row -> Transaction m a) -> Transaction m a @@ -109,12 +130,23 @@ class (Monad m) => MonadPostgres (m :: Type -> Type) where -- Only handlers should run transactions. runTransaction :: Transaction m a -> m a --- | Run a query, passing parameters. -query :: forall m params r. (PG.ToRow params, PG.FromRow r, Typeable params, Typeable r, MonadPostgres m) => PG.Query -> params -> Transaction m [r] +-- | Run a query, passing parameters. Prefer 'queryWith' if possible. +query :: + forall m params r. + (PG.ToRow params, PG.FromRow r, Typeable params, Typeable r, MonadPostgres m) => + PG.Query -> + params -> + Transaction m [r] query qry params = queryWith qry params (Decoder PG.fromRow) --- | Run a query without any parameters. -query_ :: forall m r. (Typeable r, PG.FromRow r, MonadPostgres m) => PG.Query -> Transaction m [r] +-- | Run a query without any parameters. Prefer 'queryWith' if possible. +-- +-- TODO: I think(?) this can always be replaced by passing @()@ to 'query', remove? +query_ :: + forall m r. + (Typeable r, PG.FromRow r, MonadPostgres m) => + PG.Query -> + Transaction m [r] query_ qry = queryWith_ qry (Decoder PG.fromRow) -- TODO: implement via fold, so that the result doesn’t have to be realized in memory @@ -153,7 +185,10 @@ querySingleRowMaybe qry params = do -- that a database function can error out, should probably handled by the instances. more -> throwM $ SingleRowError {numberOfRowsReturned = (List.length more)} -ensureSingleRow :: (MonadThrow m) => [a] -> m a +ensureSingleRow :: + (MonadThrow m) => + [a] -> + m a ensureSingleRow = \case -- TODO: Should we MonadThrow this here? It’s really an implementation detail of MonadPostgres -- that a database function can error out, should probably handled by the instances. @@ -167,6 +202,52 @@ ensureSingleRow = \case List.length more } +ensureNoneOrSingleRow :: + (MonadThrow m) => + [a] -> + m (Maybe a) +ensureNoneOrSingleRow = \case + -- TODO: Should we MonadThrow this here? It’s really an implementation detail of MonadPostgres + -- that a database function can error out, should probably handled by the instances. + [] -> pure Nothing + [one] -> pure $ Just one + more -> + throwM $ + SingleRowError + { numberOfRowsReturned = + -- TODO: this is VERY bad, because it requires to parse the full database output, even if there’s 10000000000 elements + List.length more + } + +-- | Run a query, passing parameters, and fold over the resulting rows. +-- +-- This doesn’t have to realize the full list of results in memory, +-- rather results are streamed incrementally from the database. +-- +-- When dealing with small results, it may be simpler (and perhaps faster) to use query instead. +-- +-- The results are folded strictly by the 'Fold.Fold' that is passed. +-- +-- If you can, prefer aggregating in the database itself. +foldRowsWith :: + forall row params m b. + ( MonadPostgres m, + PG.ToRow params, + Typeable row, + Typeable params + ) => + PG.Query -> + params -> + Decoder row -> + Fold.Fold row b -> + Transaction m b +foldRowsWith qry params decoder = Fold.purely f + where + f :: forall x. (x -> row -> x) -> x -> (x -> b) -> Transaction m b + f acc init extract = do + x <- foldRowsWithAcc qry params decoder init (\a r -> pure $ acc a r) + pure $ extract x + newtype Transaction m a = Transaction {unTransaction :: (ReaderT Connection m a)} deriving newtype ( Functor, @@ -180,9 +261,6 @@ newtype Transaction m a = Transaction {unTransaction :: (ReaderT Connection m a) Otel.MonadTracer ) -runTransaction' :: Connection -> Transaction m a -> m a -runTransaction' conn transaction = runReaderT transaction.unTransaction conn - -- | [Resource Pool](http://hackage.haskell.org/package/resource-pool-0.2.3.2/docs/Data-Pool.html) configuration. data PoolingInfo = PoolingInfo { -- | Minimal amount of resources that are @@ -237,17 +315,41 @@ initMonadPostgres logInfoFn connectInfo poolingInfo = do IO () destroyPGConnPool p = Pool.destroyAllResources p +-- | Improve a possible error message, by adding some context to it. +-- +-- The given Exception type is caught, 'show'n and pretty-printed. +-- +-- In case we get an `IOError`, we display it in a reasonable fashion. +addErrorInformation :: + forall exc a. + (Exception exc) => + Text.Text -> + IO a -> + IO a +addErrorInformation msg io = + io + & try @exc + <&> first (showPretty >>> newError >>> errorContext msg) + & try @IOError + <&> first (showToError >>> errorContext "IOError" >>> errorContext msg) + <&> join @(Either Error) + >>= unwrapIOError + -- | Catch any Postgres exception that gets thrown, -- print the query that was run and the query parameters, -- then rethrow inside an 'Error'. handlePGException :: forall a params tools m. - (ToRow params, MonadUnliftIO m, MonadLogger m, HasField "pgFormat" tools Tool) => + ( ToRow params, + MonadUnliftIO m, + MonadLogger m, + HasField "pgFormat" tools Tool + ) => tools -> Text -> Query -> -- | Depending on whether we used `format` or `formatMany`. - Either params [params] -> + Either params (NonEmpty params) -> IO a -> Transaction m a handlePGException tools queryType query' params io = do @@ -289,7 +391,11 @@ withPGTransaction connPool f = connPool (\conn -> Postgres.withTransaction conn (f conn)) -runPGTransactionImpl :: (MonadUnliftIO m) => m (Pool Postgres.Connection) -> Transaction m a -> m a +runPGTransactionImpl :: + (MonadUnliftIO m) => + m (Pool Postgres.Connection) -> + Transaction m a -> + m a {-# INLINE runPGTransactionImpl #-} runPGTransactionImpl zoom (Transaction transaction) = do pool <- zoom @@ -337,7 +443,7 @@ executeManyImpl :: m tools -> m DebugLogDatabaseQueries -> Query -> - [params] -> + NonEmpty params -> Transaction m (Label "numberOfRowsAffected" Natural) executeManyImpl zoomTools zoomDebugLogDatabaseQueries qry params = Otel.inSpan' "Postgres Query (execute)" Otel.defaultSpanArguments $ \span -> do @@ -345,7 +451,7 @@ executeManyImpl zoomTools zoomDebugLogDatabaseQueries qry params = logDatabaseQueries <- lift @Transaction zoomDebugLogDatabaseQueries traceQueryIfEnabled tools span logDatabaseQueries qry (HasMultiParams params) conn <- Transaction ask - PG.executeMany conn qry params + PG.executeMany conn qry (params & toList) & handlePGException tools "executeMany" qry (Right params) >>= toNumberOfRowsAffected "executeManyImpl" @@ -364,7 +470,7 @@ executeManyReturningWithImpl :: m tools -> m DebugLogDatabaseQueries -> Query -> - [params] -> + NonEmpty params -> Decoder r -> Transaction m [r] {-# INLINE executeManyReturningWithImpl #-} @@ -374,33 +480,45 @@ executeManyReturningWithImpl zoomTools zoomDebugLogDatabaseQueries qry params (D logDatabaseQueries <- lift @Transaction zoomDebugLogDatabaseQueries traceQueryIfEnabled tools span logDatabaseQueries qry (HasMultiParams params) conn <- Transaction ask - PG.returningWith fromRow conn qry params + PG.returningWith fromRow conn qry (params & toList) & handlePGException tools "executeManyReturning" qry (Right params) -foldRowsImpl :: - (FromRow row, ToRow params, MonadUnliftIO m, MonadLogger m, HasField "pgFormat" tools Tool) => +foldRowsWithAccImpl :: + ( ToRow params, + MonadUnliftIO m, + MonadLogger m, + HasField "pgFormat" tools Tool, + Otel.MonadTracer m + ) => m tools -> + m DebugLogDatabaseQueries -> Query -> params -> + Decoder row -> a -> (a -> row -> Transaction m a) -> Transaction m a -{-# INLINE foldRowsImpl #-} -foldRowsImpl zoomTools qry params accumulator f = do - conn <- Transaction ask - tools <- lift @Transaction zoomTools - withRunInIO - ( \runInIO -> - do - PG.fold - conn - qry - params - accumulator - (\acc row -> runInIO $ f acc row) - & handlePGException tools "fold" qry (Left params) - & runInIO - ) +{-# INLINE foldRowsWithAccImpl #-} +foldRowsWithAccImpl zoomTools zoomDebugLogDatabaseQueries qry params (Decoder rowParser) accumulator f = do + Otel.inSpan' "Postgres Query (foldRowsWithAcc)" Otel.defaultSpanArguments $ \span -> do + tools <- lift @Transaction zoomTools + logDatabaseQueries <- lift @Transaction zoomDebugLogDatabaseQueries + traceQueryIfEnabled tools span logDatabaseQueries qry (HasSingleParam params) + conn <- Transaction ask + withRunInIO + ( \runInIO -> + do + PG.foldWithOptionsAndParser + PG.defaultFoldOptions + rowParser + conn + qry + params + accumulator + (\acc row -> runInIO $ f acc row) + & handlePGException tools "fold" qry (Left params) + & runInIO + ) pgFormatQueryNoParams' :: (MonadIO m, MonadLogger m, HasField "pgFormat" tools Tool) => @@ -410,18 +528,38 @@ pgFormatQueryNoParams' :: pgFormatQueryNoParams' tools q = lift $ pgFormatQueryByteString tools q.fromQuery -pgFormatQuery :: (ToRow params, MonadIO m) => Query -> params -> Transaction m ByteString +pgFormatQuery :: + (ToRow params, MonadIO m) => + Query -> + params -> + Transaction m ByteString pgFormatQuery qry params = Transaction $ do conn <- ask liftIO $ PG.formatQuery conn qry params -pgFormatQueryMany :: (MonadIO m, ToRow params) => Query -> [params] -> Transaction m ByteString +pgFormatQueryMany :: + (MonadIO m, ToRow params) => + Query -> + NonEmpty params -> + Transaction m ByteString pgFormatQueryMany qry params = Transaction $ do conn <- ask - liftIO $ PG.formatMany conn qry params + liftIO $ + PG.formatMany + conn + qry + ( params + -- upstream is partial on empty list, see https://github.com/haskellari/postgresql-simple/issues/129 + & toList + ) queryWithImpl :: - (ToRow params, MonadUnliftIO m, MonadLogger m, HasField "pgFormat" tools Tool, Otel.MonadTracer m) => + ( ToRow params, + MonadUnliftIO m, + MonadLogger m, + HasField "pgFormat" tools Tool, + Otel.MonadTracer m + ) => m tools -> m DebugLogDatabaseQueries -> Query -> @@ -438,7 +576,15 @@ queryWithImpl zoomTools zoomDebugLogDatabaseQueries qry params (Decoder fromRow) PG.queryWith fromRow conn qry params & handlePGException tools "query" qry (Left params) -queryWithImpl_ :: (MonadUnliftIO m, MonadLogger m, HasField "pgFormat" tools Tool) => m tools -> Query -> Decoder r -> Transaction m [r] +queryWithImpl_ :: + ( MonadUnliftIO m, + MonadLogger m, + HasField "pgFormat" tools Tool + ) => + m tools -> + Query -> + Decoder r -> + Transaction m [r] {-# INLINE queryWithImpl_ #-} queryWithImpl_ zoomTools qry (Decoder fromRow) = do tools <- lift @Transaction zoomTools @@ -446,18 +592,6 @@ queryWithImpl_ zoomTools qry (Decoder fromRow) = do liftIO (PG.queryWith_ fromRow conn qry) & handlePGException tools "query" qry (Left ()) -pgQuery :: (ToRow params, FromRow r, MonadUnliftIO m, MonadLogger m, HasField "pgFormat" tools Tool) => tools -> Query -> params -> Transaction m [r] -pgQuery tools qry params = do - conn <- Transaction ask - PG.query conn qry params - & handlePGException tools "query" qry (Left params) - -pgQuery_ :: (FromRow r, MonadUnliftIO m, MonadLogger m, HasField "pgFormat" tools Tool) => tools -> Query -> Transaction m [r] -pgQuery_ tools qry = do - conn <- Transaction ask - PG.query_ conn qry - & handlePGException tools "query_" qry (Left ()) - data SingleRowError = SingleRowError { -- | How many columns were actually returned by the query numberOfRowsReturned :: Int @@ -467,12 +601,30 @@ data SingleRowError = SingleRowError instance Exception SingleRowError where displayException (SingleRowError {..}) = [fmt|Single row expected from SQL query result, {numberOfRowsReturned} rows were returned instead."|] -pgFormatQuery' :: (MonadIO m, ToRow params, MonadLogger m, HasField "pgFormat" tools Tool) => tools -> Query -> params -> Transaction m Text +pgFormatQuery' :: + ( MonadIO m, + ToRow params, + MonadLogger m, + HasField "pgFormat" tools Tool + ) => + tools -> + Query -> + params -> + Transaction m Text pgFormatQuery' tools q p = pgFormatQuery q p >>= lift . pgFormatQueryByteString tools -pgFormatQueryMany' :: (MonadIO m, ToRow params, MonadLogger m, HasField "pgFormat" tools Tool) => tools -> Query -> [params] -> Transaction m Text +pgFormatQueryMany' :: + ( MonadIO m, + ToRow params, + MonadLogger m, + HasField "pgFormat" tools Tool + ) => + tools -> + Query -> + NonEmpty params -> + Transaction m Text pgFormatQueryMany' tools q p = pgFormatQueryMany q p >>= lift . pgFormatQueryByteString tools @@ -481,7 +633,14 @@ pgFormatQueryMany' tools q p = postgresToolsParser :: ToolParserT IO (Label "pgFormat" Tool) postgresToolsParser = label @"pgFormat" <$> readTool "pg_format" -pgFormatQueryByteString :: (MonadIO m, MonadLogger m, HasField "pgFormat" tools Tool) => tools -> ByteString -> m Text +pgFormatQueryByteString :: + ( MonadIO m, + MonadLogger m, + HasField "pgFormat" tools Tool + ) => + tools -> + ByteString -> + m Text pgFormatQueryByteString tools queryBytes = do do (exitCode, stdout, stderr) <- @@ -492,8 +651,8 @@ pgFormatQueryByteString tools queryBytes = do case exitCode of ExitSuccess -> pure (stdout & stringToText) ExitFailure status -> do - $logWarn [fmt|pg_format failed with status {status} while formatting the query, using original query string. Is there a syntax error?|] - $logDebug + logWarn [fmt|pg_format failed with status {status} while formatting the query, using original query string. Is there a syntax error?|] + logDebug ( prettyErrorTree ( nestedMultiError "pg_format output" @@ -502,7 +661,7 @@ pgFormatQueryByteString tools queryBytes = do ) ) ) - $logDebug [fmt|pg_format stdout: stderr|] + logDebug [fmt|pg_format stdout: stderr|] pure (queryBytes & bytesToTextUtf8Lenient) data DebugLogDatabaseQueries @@ -517,7 +676,7 @@ data DebugLogDatabaseQueries data HasQueryParams param = HasNoParams | HasSingleParam param - | HasMultiParams [param] + | HasMultiParams (NonEmpty param) -- | Log the postgres query depending on the given setting traceQueryIfEnabled :: |