@@ -5,8 +5,8 @@
55{-# LANGUAGE ExistentialQuantification #-}
66{-# LANGUAGE FlexibleContexts #-}
77{-# LANGUAGE FlexibleInstances #-}
8−{-# LANGUAGE GADTs #-}
98{-# LANGUAGE GeneralizedNewtypeDeriving #-}
9+{-# LANGUAGE ImplicitParams #-}
1010{-# LANGUAGE MultiParamTypeClasses #-}
1111{-# LANGUAGE OverloadedStrings #-}
1212{-# LANGUAGE RankNTypes #-}
@@ -22,53 +22,36 @@
2222module Katip.Core where
2323
2424-------------------------------------------------------------------------------
25−import Control.Applicative as A
25+import Control.Applicative as A
2626import Control.AutoUpdate
2727import Control.Concurrent
28−import qualified Control.Concurrent.Async as Async
29−import Control.Concurrent.STM
30−import qualified Control.Concurrent.STM.TBQueue as BQ
31−import Control.Exception.Safe
32−import Control.Monad (unless, void, when)
3328import Control.Monad.Base
34−#if MIN_VERSION_base(4, 9, 0)
35−import qualified Control.Monad.Fail as MF
36−#endif
29+import Control.Monad.Catch
3730import Control.Monad.IO.Class
38−import Control.Monad.IO.Unlift
3931import Control.Monad.Trans.Class
4032import Control.Monad.Trans.Control
41−#if !MIN_VERSION_either(4, 5, 0)
4233import Control.Monad.Trans.Either
43−#endif
4434import Control.Monad.Trans.Except
4535import Control.Monad.Trans.Maybe
4636import Control.Monad.Trans.Reader
47−import Control.Monad.Trans.Resource (MonadResource, ResourceT,
48− transResourceT)
49−import Control.Monad.Trans.RWS.Lazy (RWST, mapRWST)
50−import qualified Control.Monad.Trans.RWS.Strict as Strict (RWST, mapRWST)
51−import Control.Monad.Trans.State.Lazy (StateT, mapStateT)
52−import qualified Control.Monad.Trans.State.Strict as Strict (StateT, mapStateT)
53−import Control.Monad.Trans.Writer.Lazy (WriterT, mapWriterT)
54−import qualified Control.Monad.Trans.Writer.Strict as Strict (WriterT,
55− mapWriterT)
56−import Data.Aeson (FromJSON (..), ToJSON (..),
57− object)
58−import qualified Data.Aeson as A
59−import Data.Foldable as FT
60−import qualified Data.HashMap.Strict as HM
37+import Control.Monad.Trans.Resource
38+import Control.Monad.Trans.State
39+import Control.Monad.Trans.Writer
40+import Data.Aeson (FromJSON (..), ToJSON (..),
41+ object)
42+import qualified Data.Aeson as A
43+import Data.Foldable as FT
44+import qualified Data.HashMap.Strict as HM
6145import Data.List
62−import qualified Data.Map.Strict as M
63−import Data.Maybe (fromMaybe)
64−import Data.Semigroup as SG
46+import qualified Data.Map.Strict as M
47+import Data.Semigroup
6548import Data.String
6649import Data.String.Conv
67−import Data.Text (Text)
68−import qualified Data.Text as T
69−import qualified Data.Text.Lazy.Builder as B
50+import Data.Text (Text)
51+import qualified Data.Text as T
52+import qualified Data.Text.Lazy.Builder as B
7053import Data.Time
71−import GHC.Generics hiding (to)
54+import GHC.Generics hiding (to)
7255#if MIN_VERSION_base(4, 8, 0)
7356#if !MIN_VERSION_base(4, 9, 0)
7457import GHC.SrcLoc
@@ -76,7 +59,7 @@ import GHC.SrcLoc
7659import GHC.Stack
7760#endif
7861import Language.Haskell.TH
79−import qualified Language.Haskell.TH.Syntax as TH
62+import qualified Language.Haskell.TH.Syntax as TH
8063import Lens.Micro
8164import Lens.Micro.TH
8265import Network.HostName
@@ -92,8 +75,8 @@ import System.Posix
9275readMay :: Read a => String -> Maybe a
9376readMay s = case [x | (x,t) <- reads s, ("","") <- lex t] of
9477 [x] -> Just x
95− [] -> Nothing -- no parse
96− _ -> Nothing -- Ambiguous parse
78+ [] -> Nothing -- no parse
79+ _ -> Nothing -- Ambiguous parse
9780
9881
9982-------------------------------------------------------------------------------
@@ -103,7 +86,7 @@ readMay s = case [x | (x,t) <- reads s, ("","") <- lex t] of
10386-- IsString/OverloadedStrings, so "foo" will result in Namespace
10487-- ["foo"].
10588newtype Namespace = Namespace { unNamespace :: [Text] }
106− deriving (Eq,Show,Read,Ord,Generic,ToJSON,FromJSON,SG.Semigroup,Monoid)
89+ deriving (Eq,Show,Read,Ord,Generic,ToJSON,FromJSON,Semigroup,Monoid)
10790
10891instance IsString Namespace where
10992 fromString s = Namespace [fromString s]
@@ -143,19 +126,19 @@ data Severity
143126-- - 'V3' implies the maximum amount of payload information.
144127-- - Anything in between is left to the discretion of the developer.
145128data Verbosity = V0 | V1 | V2 | V3
146− deriving (Eq, Ord, Show, Read, Generic, Enum, Bounded)
129+ deriving (Eq, Ord, Show, Read, Generic, Enum)
147130
148131
149132-------------------------------------------------------------------------------
150133renderSeverity :: Severity -> Text
151134renderSeverity s = case s of
152− DebugS -> "Debug"
153− InfoS -> "Info"
154− NoticeS -> "Notice"
155− WarningS -> "Warning"
156− ErrorS -> "Error"
157− CriticalS -> "Critical"
158− AlertS -> "Alert"
135+ DebugS -> "Debug"
136+ InfoS -> "Info"
137+ NoticeS -> "Notice"
138+ WarningS -> "Warning"
139+ ErrorS -> "Error"
140+ CriticalS -> "Critical"
141+ AlertS -> "Alert"
159142 EmergencyS -> "Emergency"
160143
161144
@@ -181,29 +164,14 @@ instance FromJSON Severity where
181164 parseJSON = A.withText "Severity" parseSeverity
182165 where
183166 parseSeverity t = case textToSeverity t of
184− Just x -> return x
167+ Just x -> return x
185168 Nothing -> fail $ "Invalid Severity " ++ toS t
186169
187−instance ToJSON Verbosity where
188− toJSON s = A.String $ case s of
189− V0 -> "V0"
190− V1 -> "V1"
191− V2 -> "V2"
192− V3 -> "V3"
193−
194−instance FromJSON Verbosity where
195− parseJSON = A.withText "Verbosity" $ \s -> case s of
196− "V0" -> return V0
197− "V1" -> return V1
198− "V2" -> return V2
199− "V3" -> return V3
200− _ -> fail $ "Invalid Verbosity " ++ toS s
201−
202170
203171-------------------------------------------------------------------------------
204172-- | Log message with Builder underneath; use '<>' to concat in O(1).
205173newtype LogStr = LogStr { unLogStr :: B.Builder }
206− deriving (Generic, Show, Eq)
174+ deriving (Generic, Show)
207175
208176instance IsString LogStr where
209177 fromString = LogStr . B.fromString
@@ -250,9 +218,7 @@ newtype ThreadIdText = ThreadIdText {
250218
251219
252220mkThreadIdText :: ThreadId -> ThreadIdText
253−mkThreadIdText = ThreadIdText . stripPrefix' "ThreadId " . T.pack . show
254− where
255− stripPrefix' pfx t = fromMaybe t (T.stripPrefix pfx t)
221+mkThreadIdText = ThreadIdText . T.pack . show
256222
257223
258224-------------------------------------------------------------------------------
@@ -272,62 +238,31 @@ data Item a = Item {
272238 } deriving (Generic, Functor)
273239makeLenses ''Item
274240
275−-- Manual instance because 'Loc' has no 'Eq' and 'Show' instances in old
276−-- versions of template-haskell (< 2.10)
277−instance Eq a => Eq (Item a) where
278− a == b = FT.and [ _itemApp a == _itemApp b
279− , _itemEnv a == _itemEnv b
280− , _itemSeverity a == _itemSeverity b
281− , _itemThread a == _itemThread b
282− , _itemHost a == _itemHost b
283− , _itemProcess a == _itemProcess b
284− , _itemPayload a == _itemPayload b
285− , _itemMessage a == _itemMessage b
286− , _itemTime a == _itemTime b
287− , _itemNamespace a == _itemNamespace b
288− , case (_itemLoc a, _itemLoc b) of
289− (Nothing, Nothing) -> True
290− (Just l1, Just l2) -> FT.and [ loc_filename l1 == loc_filename l2
291− , loc_package l1 == loc_package l2
292− , loc_module l1 == loc_module l2
293− , loc_start l1 == loc_start l2
294− , loc_end l1 == loc_end l2
295− ]
296− _ -> False
297− ]
298241
299242instance Show a => Show (Item a) where
300− showsPrec d Item{..} = showParen (d >= 11) ( showString "Item {"
301− . field "_itemApp" _itemApp
302− . field "_itemEnv" _itemEnv
303− . field "_itemSeverity" _itemSeverity
304− . field "_itemThread" _itemThread
305− . field "_itemHost" _itemHost
306− . field "_itemProcess" _itemProcess
307− . field "_itemPayload" _itemPayload
308− . field "_itemMessage" _itemMessage
309− . field "_itemTime" _itemTime
310− . field "_itemNamespace" _itemNamespace
311− . showString "_itemLoc = " . shows (LocShow <$> _itemLoc)
312− . showChar '}'
313− )
314− where
315− field n v = showString n . showString " = " . shows v . showString ", "
243+ show Item{..} = "Item {_itemApp = " ++ show _itemApp ++ ", " ++
244+ "_itemEnv = " ++ show _itemEnv ++ ", " ++
245+ "_itemSeverity = " ++ show _itemSeverity ++ ", " ++
246+ "_itemThread = " ++ show _itemThread ++ ", " ++
247+ "_itemHost = " ++ show _itemHost ++ ", " ++
248+ "_itemProcess = " ++ show _itemProcess ++ ", " ++
249+ "_itemPayload = " ++ show _itemPayload ++ ", " ++
250+ "_itemMessage = " ++ show _itemMessage ++ ", " ++
251+ "_itemTime = " ++ show _itemTime ++ ", " ++
252+ "_itemNamespace = " ++ show _itemNamespace ++ ", " ++
253+ "_itemLoc = " ++ show (LocShow <$> _itemLoc) ++ "}"
254+
316255
317256newtype LocShow = LocShow Loc
318257
319258
320259instance Show LocShow where
321− showsPrec d (LocShow Loc{..}) = showParen (d >= 11) ( showString "Loc {"
322− . field "loc_filename" loc_filename
323− . field "loc_package" loc_package
324− . field "loc_module" loc_module
325− . field "loc_start" loc_start
326− . showString "loc_end = " . shows loc_end
327− . showChar '}'
328− )
329− where
330− field n v = showString n . showString " = " . shows v . showString ", "
260+ show (LocShow Loc{..}) =
261+ "Loc {loc_filename = " ++ show loc_filename ++ ", " ++
262+ "loc_package = " ++ show loc_package ++ ", " ++
263+ "loc_module = " ++ show loc_module ++ ", " ++
264+ "loc_start = " ++ show loc_start ++ ", " ++
265+ "loc_end = " ++ show loc_end ++ "}"
331266
332267
333268instance ToJSON a => ToJSON (Item a) where
@@ -408,7 +343,7 @@ instance FromJSON ProcessIDJs where
408343 parseJSON = A.withText "ProcessID" parseProcessID
409344 where
410345 parseProcessID t = case textToProcessID t of
411− Just p -> return $ ProcessIDJs p
346+ Just p -> return $ ProcessIDJs p
412347 Nothing -> fail $ "Invalid ProcessIDJs " ++ toS t
413348
414349
@@ -445,7 +380,7 @@ class ToObject a where
445380 default toObject :: ToJSON a => a -> A.Object
446381 toObject v = case toJSON v of
447382 A.Object o -> o
448− _ -> mempty
383+ _ -> mempty
449384
450385instance ToObject ()
451386instance ToObject A.Object
@@ -497,7 +432,7 @@ instance ToObject SimpleLogPayload
497432
498433instance LogItem SimpleLogPayload where
499434 payloadKeys V0 _ = SomeKeys []
500− payloadKeys _ _ = AllKeys
435+ payloadKeys _ _ = AllKeys
501436
502437
503438instance Semigroup SimpleLogPayload where
@@ -520,7 +455,7 @@ sl a b = SimpleLogPayload [(a, AnyLogPayload b)]
520455-- automatically bubble higher verbosity levels to lower ones.
521456payloadObject :: LogItem a => Verbosity -> a -> A.Object
522457payloadObject verb a = case FT.foldMap (flip payloadKeys a) [(V0)..verb] of
523− AllKeys -> toObject a
458+ AllKeys -> toObject a
524459 SomeKeys ks -> HM.filterWithKey (\ k _ -> k `FT.elem` ks) $ toObject a
525460
526461
@@ -540,107 +475,49 @@ itemJson verb a = toJSON $ a & itemPayload %~ payloadObject verb
540475--
541476-- Scribes should always take a 'Severity' and 'Verbosity'.
542477--
543−-- Severity is used to __exclude log messages__ that are lower than
544−-- the provided Severity. For instance, if the user passes InfoS,
545−-- DebugS items should be ignored. Katip provides the 'permitItem'
546−-- utility for this. The user or the scribe may use 'permitAND' and
547−-- 'permitOR' to further customize this filtering, even dynamically if
548−-- they wish to.
478+-- Severity is used to *exclude log messages* that are < the provided
479+-- Severity. For instance, if the user passes InfoS, DebugS items
480+-- should be ignored. Katip provides the 'permitItem' utility for this.
549481--
550482-- Verbosity is used to select keys from the log item's payload. Each
551483-- 'LogItem' instance describes what keys should be retained for each
552484-- Verbosity level. Use the 'payloadObject' utility for extracting the keys
553−-- that should be written.
485+-- that should be permitted.
554486--
555−-- Scribes provide a finalizer IO action ('scribeFinalizer') that is
556−-- meant to synchronously flush any remaining writes and clean up any
557−-- resources acquired when the scribe was created. Internally, katip
558−-- keeps a buffer for each scribe's writes. When 'closeScribe' or
559−-- 'closeScribes' is called, that buffer stops accepting new log
560−-- messages and after the last item in its buffer is sent to 'liPush',
561−-- calls the finalizer. Thus, when the finalizer returns, katip can
562−-- assume that all resources are cleaned up and all log messages are
563−-- durably written.
487+-- There is no built-in mechanism in katip for telling a scribe that
488+-- its time to shut down. 'unregisterScribe' merely drops it from the
489+-- 'LogEnv'. This means there are 2 ways to handle resources as a scribe:
564490--
565−-- While katip internally buffers messages per 'ScribeSettings', it
566−-- sends them one at a time to the scribe. Depending on the scribe
567−-- itself, it may make sense for that scribe to keep its own internal
568−-- buffer to batch-send logs if writing items one at a time is not
569−-- efficient. The scribe implementer must be sure that on
570−-- finalization, all writes are committed synchronously.
571−
572−-- | Signature of a function passed to `Scribe` constructor and
573−-- mkScribe* functions that decides which messages to be
574−-- logged. Typically filters based on 'Severity', but can be
575−-- combined with other, custom logic with 'permitAND' and 'permitOR'
576−type PermitFunc = forall a. Item a -> IO Bool
577−
578−
579−-- | AND together 2 permit functions
580−permitAND :: PermitFunc -> PermitFunc -> PermitFunc
581−permitAND f1 f2 = \a -> liftA2 (&&) (f1 a) (f2 a)
582−
583−-- | OR together 2 permit functions
584−permitOR :: PermitFunc -> PermitFunc -> PermitFunc
585−permitOR f1 f2 = \a -> liftA2 (||) (f1 a) (f2 a)
491+-- 1. Pass in the resource when the scribe is created. Handle
492+-- allocation and release of the resource elsewhere. This is what the
493+-- Handle scribe does.
494+--
495+-- 2. Return a finalizing function that tells the scribe to shut
496+-- down. @katip-elasticsearch@'s @mkEsScribe@ returns an @IO (Scribe,
497+-- IO ())@. The finalizer will flush any queued log messages and shut
498+-- down gracefully before returning. This can be hooked into your
499+-- application's shutdown routine to ensure you never miss any log
500+-- messages on shutdown.
501+data Scribe = Scribe {
502+ liPush :: forall a. LogItem a => Item a -> IO ()
503+ }
586504
587505
588−data Scribe = Scribe {
589− liPush :: forall a. LogItem a => Item a -> IO ()
590− -- ^ How do we write an item to the scribe's output?
591− , scribeFinalizer :: IO ()
592− -- ^ Provide a __blocking__ finalizer to call when your scribe is
593− -- removed. All pending writes should be flushed synchronously. If
594− -- this is not relevant to your scribe, return () is fine.
595− , scribePermitItem :: PermitFunc
596− -- ^ Provide a filtering function to allow the item to be logged,
597− -- or not. It can check Severity or some string in item's
598− -- body. The initial value of this is usually created from
599− -- 'permitItem'. Scribes and users can customize this by ANDing
600− -- or ORing onto the default with 'permitAND' or 'permitOR'
601− }
602−
603−
604−whenM :: Monad m => m Bool -> m () -> m ()
605−whenM mbool = (>>=) mbool . flip when
606−
607−
608−-- | Combine two scribes. Publishes to the left scribe if the left
609−-- would permit the item and to the right scribe if the right would
610−-- permit the item. Finalizers are called in sequence from left to
611−-- right.
612506instance Semigroup Scribe where
613− (Scribe pushA finA permitA) <> (Scribe pushB finB permitB) =
614− Scribe (\item -> whenM (permitA item) (pushA item)
615− >> whenM (permitB item) (pushB item)
616− )
617− (finA `finally` finB)
618− (permitOR permitA permitB)
507+ (Scribe a) <> (Scribe b) = Scribe $ \ item -> do
508+ a item
509+ b item
619510
620511
621512instance Monoid Scribe where
622− mempty = Scribe (const (return ())) (return ()) (permitItem DebugS)
513+ mempty = Scribe $ const $ return ()
623514 mappend = (<>)
624515
625516
626−-------------------------------------------------------------------------------
627−data ScribeHandle = ScribeHandle {
628− shScribe :: Scribe
629− , shChan :: BQ.TBQueue WorkerMessage
630− }
631−
632−
633−-------------------------------------------------------------------------------
634−data WorkerMessage where
635− NewItem :: LogItem a => Item a -> WorkerMessage
636− PoisonPill :: WorkerMessage
637−
638−
639517-------------------------------------------------------------------------------
640518-- | Should this item be logged given the user's maximum severity?
641−-- Most new scribes will use this as a base for their 'PermitFunc'
642−permitItem :: Monad m => Severity -> Item a -> m Bool
643−permitItem sev item = return (_itemSeverity item >= sev)
519+permitItem :: Severity -> Item a -> Bool
520+permitItem sev i = _itemSeverity i >= sev
644521
645522
646523-------------------------------------------------------------------------------
@@ -659,16 +536,16 @@ data LogEnv = LogEnv {
659536 -- 'AutoUpdate' for high volume logs but note that this may cause
660537 -- some output forms to display logs out of order. Alternatively,
661538 -- you could just use 'getCurrentTime'.
662− , _logEnvScribes :: M.Map Text ScribeHandle
539+ , _logEnvScribes :: M.Map Text Scribe
663540 }
664541makeLenses ''LogEnv
665542
666543
667544-------------------------------------------------------------------------------
668−-- | Create a reasonable default InitLogEnv. Uses an 'AutoUpdate' which
669−-- updates the timer every 1ms. If you need even more timestamp
670−-- precision at the cost of performance, consider setting
671−-- '_logEnvTimer' with 'getCurrentTime'.
545+-- | Create a reasonable default InitLogEnv. Uses an 'AutoUdate' with
546+-- the default settings as the timer. If you are concerned about
547+-- timestamp precision or event ordering in log outputs like
548+-- ElasticSearch, you should replace the timer with 'getCurrentTime'
672549initLogEnv
673550 :: Namespace
674551 -- ^ A base namespace for this application
@@ -680,123 +557,45 @@ initLogEnv an env = LogEnv
680557 <*> getProcessID
681558 <*> pure an
682559 <*> pure env
683− <*> mkAutoUpdate defaultUpdateSettings { updateAction = getCurrentTime, updateFreq = 1000 }
560+ <*> mkAutoUpdate defaultUpdateSettings { updateAction = getCurrentTime }
684561 <*> pure mempty
685562
686563
687564-------------------------------------------------------------------------------
688565-- | Add a scribe to the list. All future log calls will go to this
689−-- scribe in addition to the others. Writes will be buffered per the
690−-- ScribeSettings to prevent slow scribes from slowing down
691−-- logging. Writes will be dropped if the buffer fills.
566+-- scribe in addition to the others.
692567registerScribe
693568 :: Text
694569 -- ^ Name the scribe
695570 -> Scribe
696− -> ScribeSettings
697571 -> LogEnv
698− -> IO LogEnv
699−registerScribe nm scribe ScribeSettings {..} le = do
700− queue <- atomically (BQ.newTBQueue (fromIntegral _scribeBufferSize))
701− worker <- spawnScribeWorker scribe queue
702− let fin = do
703− atomically (BQ.writeTBQueue queue PoisonPill)
704− -- wait for our worker to finish final write
705− void (Async.waitCatch worker)
706− -- wait for scribe to finish final write
707− void (scribeFinalizer scribe)
708−
709− let sh = ScribeHandle (scribe { scribeFinalizer = fin }) queue
710− return (le & logEnvScribes %~ M.insert nm sh)
711−
712−
713−-------------------------------------------------------------------------------
714−spawnScribeWorker :: Scribe -> BQ.TBQueue WorkerMessage -> IO (Async.Async ())
715−spawnScribeWorker (Scribe write _ _) queue = Async.async go
716− where
717− go = do
718− newCmd <- atomically (BQ.readTBQueue queue)
719− case newCmd of
720− NewItem a -> do
721− -- Swallow any direct exceptions from the
722− -- scribe. safe-exceptions won't catch async exceptions.
723− void (tryAny (write a))
724− go
725− PoisonPill -> return ()
726−
727−
728−-------------------------------------------------------------------------------
729−data ScribeSettings = ScribeSettings {
730− _scribeBufferSize :: Int
731− }
732− deriving (Show, Eq)
733−
734−makeLenses ''ScribeSettings
735−
736−
737−-- | Reasonable defaults for a scribe. Buffer
738−-- size of 4096.
739−defaultScribeSettings :: ScribeSettings
740−defaultScribeSettings = ScribeSettings 4096
572+ -> LogEnv
573+registerScribe nm h = logEnvScribes %~ M.insert nm h
741574
742575
743576-------------------------------------------------------------------------------
744−-- | Remove a scribe from the environment. This does __not__ finalize
745−-- the scribe. This mainly only makes sense to use with something like
746−-- MonadReader's @local@ function to temporarily disavow a single
747−-- logger for a block of code.
577+-- | Remove a scribe from the list. All future log calls will no
578+-- longer use this scribe. If the given scribe doesn't exist, its a no-op.
748579unregisterScribe
749580 :: Text
750581 -- ^ Name of the scribe
751582 -> LogEnv
752583 -> LogEnv
753−unregisterScribe nm = logEnvScribes %~ M.delete nm
584+unregisterScribe nm = logEnvScribes %~ M.delete nm
754585
755586
756587-------------------------------------------------------------------------------
757−-- | Unregister __all__ scribes. Note that this is __not__ for closing or
758−-- finalizing scribes, use 'closeScribes' for that. This mainly only
759−-- makes sense to use with something like MonadReader's @local@
760−-- function to temporarily disavow any loggers for a block of code.
588+-- | Unregister *all* scribes. Logs will go off into space from this
589+-- point onward until new scribes are added. Note that you could use
590+-- this with `local` if you're using a Reader based stack to
591+-- temporarily disable log output. See `katipNoLogging` for an
592+-- example.
761593clearScribes
762594 :: LogEnv
763595 -> LogEnv
764596clearScribes = logEnvScribes .~ mempty
765597
766598
767−-------------------------------------------------------------------------------
768−-- | Finalize a scribe. The scribe is removed from the environment,
769−-- its finalizer is called so that it can never be written to again
770−-- and all pending writes are flushed. Note that this will throw any
771−-- exceptions yoru finalizer will throw, and that LogEnv is immutable,
772−-- so it will not be removed in that case.
773−closeScribe
774− :: Text
775− -- ^ Name of the scribe
776− -> LogEnv
777− -> IO LogEnv
778−closeScribe nm le = do
779− maybe (return ()) (scribeFinalizer . shScribe) (M.lookup nm (_logEnvScribes le))
780− return (le & logEnvScribes %~ M.delete nm)
781−
782−
783−-------------------------------------------------------------------------------
784−-- | Call this at the end of your program. This is a blocking call
785−-- that stop writing to a scribe's queue, waits for the queue to
786−-- empty, finalizes each scribe in the log environment and then
787−-- removes it. Finalizers are all run even if one of them throws, but
788−-- the exception will be re-thrown at the end.
789−closeScribes
790− :: LogEnv
791− -> IO LogEnv
792−closeScribes le = do
793− -- We want to run every finalizer here so we'll not save
794− -- intermediate logenvs and just clear scribes at the end.
795− let actions = [void (closeScribe k le) | k <- M.keys (_logEnvScribes le)]
796− FT.foldr finally (return ()) actions
797− return (le & logEnvScribes .~ mempty)
798−
799−
800599-------------------------------------------------------------------------------
801600-- | Monads where katip logging actions can be performed. Katip is the
802601-- most basic logging monad. You will typically use this directly if
@@ -807,86 +606,44 @@ closeScribes le = do
807606-- which keeps a namespace and merged context. You can write simple
808607-- functions that add additional namespacing and merges additional
809608-- context on the fly.
810−--
811−-- 'localLogEnv' was added to allow for lexically-scoped modifications
812−-- of the log env that are reverted when the supplied monad
813−-- completes. 'katipNoLogging', for example, uses this to temporarily
814−-- pause log outputs.
815609class MonadIO m => Katip m where
816610 getLogEnv :: m LogEnv
817− localLogEnv :: (LogEnv -> LogEnv) -> m a -> m a
818611
819612
820613instance Katip m => Katip (ReaderT s m) where
821614 getLogEnv = lift getLogEnv
822− localLogEnv = mapReaderT . localLogEnv
823615
824616
825−#if !MIN_VERSION_either(4, 5, 0)
826617instance Katip m => Katip (EitherT s m) where
827618 getLogEnv = lift getLogEnv
828− localLogEnv = mapEitherT . localLogEnv
829−#endif
830−
831619
832620instance Katip m => Katip (ExceptT s m) where
833621 getLogEnv = lift getLogEnv
834− localLogEnv = mapExceptT . localLogEnv
835−
836622
837623instance Katip m => Katip (MaybeT m) where
838624 getLogEnv = lift getLogEnv
839− localLogEnv = mapMaybeT . localLogEnv
840625
841626
842627instance Katip m => Katip (StateT s m) where
843628 getLogEnv = lift getLogEnv
844− localLogEnv = mapStateT . localLogEnv
845−
846−
847−instance (Katip m, Monoid w) => Katip (RWST r w s m) where
848− getLogEnv = lift getLogEnv
849− localLogEnv = mapRWST . localLogEnv
850−
851−
852−instance (Katip m, Monoid w) => Katip (Strict.RWST r w s m) where
853− getLogEnv = lift getLogEnv
854− localLogEnv = Strict.mapRWST . localLogEnv
855−
856−
857−instance Katip m => Katip (Strict.StateT s m) where
858− getLogEnv = lift getLogEnv
859− localLogEnv = Strict.mapStateT . localLogEnv
860629
861630
862631instance (Katip m, Monoid s) => Katip (WriterT s m) where
863632 getLogEnv = lift getLogEnv
864− localLogEnv = mapWriterT . localLogEnv
865−
866−
867−instance (Katip m, Monoid s) => Katip (Strict.WriterT s m) where
868− getLogEnv = lift getLogEnv
869− localLogEnv = Strict.mapWriterT . localLogEnv
870−
871633
872634instance (Katip m) => Katip (ResourceT m) where
873635 getLogEnv = lift getLogEnv
874− localLogEnv = transResourceT . localLogEnv
875636
876637
877638-------------------------------------------------------------------------------
878−-- | A concrete monad you can use to run logging actions. Use this if
879−-- you prefer an explicit monad transformer stack and adding layers as
880−-- opposed to implementing 'Katip' for your monad.
639+-- | A concrete monad you can use to run logging actions.
881640newtype KatipT m a = KatipT { unKatipT :: ReaderT LogEnv m a }
882641 deriving ( Functor, Applicative, Monad, MonadIO
883− , MonadMask, MonadCatch, MonadThrow, MonadResource, MonadTrans
884− , MonadBase b)
642+ , MonadMask, MonadCatch, MonadThrow, MonadTrans, MonadBase b)
885643
886644
887645instance MonadIO m => Katip (KatipT m) where
888646 getLogEnv = KatipT ask
889− localLogEnv f (KatipT m) = KatipT $ local f m
890647
891648
892649instance MonadTransControl KatipT where
@@ -902,21 +659,6 @@ instance (MonadBaseControl b m) => MonadBaseControl b (KatipT m) where
902659 liftBaseWith = defaultLiftBaseWith
903660 restoreM = defaultRestoreM
904661
905−instance MonadUnliftIO m => MonadUnliftIO (KatipT m) where
906−#if MIN_VERSION_unliftio_core(0, 2, 0)
907− withRunInIO inner = KatipT $ ReaderT $ \le -> withRunInIO $ \run ->
908− inner (run . runKatipT le)
909−#else
910− askUnliftIO = KatipT $
911− withUnliftIO $ \u ->
912− pure (UnliftIO (unliftIO u . unKatipT))
913−#endif
914−
915−#if MIN_VERSION_base(4, 9, 0)
916−instance MF.MonadFail m => MF.MonadFail (KatipT m) where
917− fail msg = lift (MF.fail msg)
918− {-# INLINE fail #-}
919−#endif
920662
921663-------------------------------------------------------------------------------
922664-- | Execute 'KatipT' on a log env.
@@ -924,17 +666,6 @@ runKatipT :: LogEnv -> KatipT m a -> m a
924666runKatipT le (KatipT f) = runReaderT f le
925667
926668
927−-------------------------------------------------------------------------------
928−-- | Disable all scribes for the given monadic action, then restore
929−-- them afterwards. Works in any Katip monad.
930−katipNoLogging
931− :: ( Katip m
932− )
933− => m a
934− -> m a
935−katipNoLogging = localLogEnv (\le -> set logEnvScribes mempty le)
936−
937−
938669-------------------------------------------------------------------------------
939670-- | Log with everything, including a source code location. This is
940671-- very low level and you typically can use 'logT' in its place.
@@ -948,43 +679,20 @@ logItem
948679 -> m ()
949680logItem a ns loc sev msg = do
950681 LogEnv{..} <- getLogEnv
951− logKatipItem =<< liftIO
952− (Item <$> pure _logEnvApp
953− <*> pure _logEnvEnv
954− <*> pure sev
955− <*> (mkThreadIdText <$> myThreadId)
956− <*> pure _logEnvHost
957− <*> pure _logEnvPid
958− <*> pure a
959− <*> pure msg
960− <*> _logEnvTimer
961− <*> pure (_logEnvApp <> ns)
962− <*> pure loc)
963−
964−-- | Log already constructed 'Item'. This is the lowest level function that other log*
965−-- functions use.
966−-- It can be useful when implementing centralised logging services.
967−logKatipItem
968− :: (A.Applicative m, LogItem a, Katip m)
969− => Item a
970− -> m ()
971−logKatipItem item = do
972− LogEnv{..} <- getLogEnv
973− liftIO $
974− FT.forM_ (M.elems _logEnvScribes) $ \ ScribeHandle {..} -> do
975− whenM (scribePermitItem shScribe item) $
976− void $ atomically (tryWriteTBQueue shChan (NewItem item))
977−
978−-------------------------------------------------------------------------------
979−tryWriteTBQueue
980− :: TBQueue a
981− -> a
982− -> STM Bool
983− -- ^ Did we write?
984−tryWriteTBQueue q a = do
985− full <- isFullTBQueue q
986− unless full (writeTBQueue q a)
987− return (not full)
682+ liftIO $ do
683+ item <- Item
684+ <$> pure _logEnvApp
685+ <*> pure _logEnvEnv
686+ <*> pure sev
687+ <*> (mkThreadIdText <$> myThreadId)
688+ <*> pure _logEnvHost
689+ <*> pure _logEnvPid
690+ <*> pure a
691+ <*> pure msg
692+ <*> _logEnvTimer
693+ <*> pure (_logEnvApp <> ns)
694+ <*> pure loc
695+ FT.forM_ (M.elems _logEnvScribes) $ \ (Scribe h) -> h item
988696
989697
990698-------------------------------------------------------------------------------
@@ -1016,10 +724,10 @@ logException
1016724 -> Severity -- ^ Severity
1017725 -> m b -- ^ Main action being run
1018726 -> m b
1019−logException a ns sev action = action `catchAny` \e -> f e >> throwM e
727+logException a ns sev action = action `catchAll` \e -> f e >> throwM e
1020728 where
1021729 f e = logF a ns sev (msg e)
1022− msg e = ls (T.pack "An exception has occurred: ") <> showLS e
730+ msg e = ls (T.pack "An exception has occured: ") <> showLS e
1023731
1024732
1025733-------------------------------------------------------------------------------
@@ -1047,14 +755,14 @@ instance TH.Lift Verbosity where
1047755
1048756
1049757instance TH.Lift Severity where
1050− lift DebugS = [| DebugS |]
1051− lift InfoS = [| InfoS |]
1052− lift NoticeS = [| NoticeS |]
1053− lift WarningS = [| WarningS |]
1054− lift ErrorS = [| ErrorS |]
758+ lift DebugS = [| DebugS |]
759+ lift InfoS = [| InfoS |]
760+ lift NoticeS = [| NoticeS |]
761+ lift WarningS = [| WarningS |]
762+ lift ErrorS = [| ErrorS |]
1055763 lift CriticalS = [| CriticalS |]
1056− lift AlertS = [| AlertS |]
1057− lift EmergencyS = [| EmergencyS |]
764+ lift AlertS = [| AlertS |]
765+ lift EmergencyS = [| EmergencyS |]
1058766
1059767
1060768-- | Lift a location into an Exp.
@@ -1073,15 +781,11 @@ liftLoc (Loc a b c (d1, d2) (e1, e2)) = [|Loc
1073781-- fill the 'Maybe Loc' gap in 'logF' of this module, and relies on implicit
1074782-- callstacks when available (GHC > 7.8).
1075783#if MIN_VERSION_base(4, 8, 0)
1076−getLoc :: HasCallStack => Maybe Loc
1077−getLoc = case getCallStack callStack of
784+getLoc :: (?loc :: CallStack) => Maybe Loc
785+getLoc = case getCallStack ?loc of
1078786 [] -> Nothing
1079− xs -> Just . toLoc . head $ filter filterKatip xs
787+ xs -> Just . toLoc . last $ xs
1080788 where
1081− filterKatip :: (String, SrcLoc) -> Bool
1082− filterKatip (_, srcloc) = not $
1083− "katip-" `isPrefixOf` srcLocPackage srcloc
1084−
1085789 toLoc :: (String, SrcLoc) -> Loc
1086790 toLoc (_, l) = Loc {
1087791 loc_filename = srcLocFile l
@@ -1112,7 +816,7 @@ logT = [| \ a ns sev msg -> logItem a ns (Just $(getLocTH)) sev msg |]
1112816
1113817
1114818-------------------------------------------------------------------------------
1115−-- | 'Loc'-tagged logging using 'GHC.Stack' when available.
819+-- | 'Loc'-tagged logging using implicit-callstacks when available.
1116820--
1117821-- This function does not require template-haskell as it
1118822-- automatically uses <https://hackage.haskell.org/package/base-4.8.2.0/docs/GHC-Stack.html#v:getCallStack implicit-callstacks>
@@ -1123,7 +827,7 @@ logT = [| \ a ns sev msg -> logItem a ns (Just $(getLocTH)) sev msg |]
1123827--
1124828-- @logLoc obj mempty InfoS "Hello world"@
1125829#if MIN_VERSION_base(4, 8, 0)
1126−logLoc :: (Applicative m, LogItem a, Katip m, HasCallStack)
830+logLoc :: (Applicative m, LogItem a, Katip m, ?loc :: CallStack)
1127831#else
1128832logLoc :: (Applicative m, LogItem a, Katip m)
1129833#endif