@@ -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
@@ -76,24 +59,19 @@ 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
83−#if mingw32_HOST_OS
84−import Katip.Compat
85−#else
8666import System.Posix
87−#endif
88−
8967-------------------------------------------------------------------------------
9068
9169
9270readMay :: Read a => String -> Maybe a
9371readMay s = case [x | (x,t) <- reads s, ("","") <- lex t] of
9472 [x] -> Just x
95− [] -> Nothing -- no parse
96− _ -> Nothing -- Ambiguous parse
73+ [] -> Nothing -- no parse
74+ _ -> Nothing -- Ambiguous parse
9775
9876
9977-------------------------------------------------------------------------------
@@ -103,7 +81,7 @@ readMay s = case [x | (x,t) <- reads s, ("","") <- lex t] of
10381-- IsString/OverloadedStrings, so "foo" will result in Namespace
10482-- ["foo"].
10583newtype Namespace = Namespace { unNamespace :: [Text] }
106− deriving (Eq,Show,Read,Ord,Generic,ToJSON,FromJSON,SG.Semigroup,Monoid)
84+ deriving (Eq,Show,Read,Ord,Generic,ToJSON,FromJSON,Semigroup,Monoid)
10785
10886instance IsString Namespace where
10987 fromString s = Namespace [fromString s]
@@ -143,35 +121,33 @@ data Severity
143121-- - 'V3' implies the maximum amount of payload information.
144122-- - Anything in between is left to the discretion of the developer.
145123data Verbosity = V0 | V1 | V2 | V3
146− deriving (Eq, Ord, Show, Read, Generic, Enum, Bounded)
124+ deriving (Eq, Ord, Show, Read, Generic, Enum)
147125
148126
149127-------------------------------------------------------------------------------
150128renderSeverity :: Severity -> Text
151129renderSeverity 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"
130+ DebugS -> "Debug"
131+ InfoS -> "Info"
132+ NoticeS -> "Notice"
133+ WarningS -> "Warning"
134+ ErrorS -> "Error"
135+ CriticalS -> "Critical"
136+ AlertS -> "Alert"
159137 EmergencyS -> "Emergency"
160138
161139
162140-------------------------------------------------------------------------------
163141textToSeverity :: Text -> Maybe Severity
164−textToSeverity = go . T.toLower
165− where
166− go "debug" = Just DebugS
167− go "info" = Just InfoS
168− go "notice" = Just NoticeS
169− go "warning" = Just WarningS
170− go "error" = Just ErrorS
171− go "critical" = Just CriticalS
172− go "alert" = Just AlertS
173− go "emergency" = Just EmergencyS
174− go _ = Nothing
142+textToSeverity "Debug" = Just DebugS
143+textToSeverity "Info" = Just InfoS
144+textToSeverity "Notice" = Just NoticeS
145+textToSeverity "Warning" = Just WarningS
146+textToSeverity "Error" = Just ErrorS
147+textToSeverity "Critical" = Just CriticalS
148+textToSeverity "Alert" = Just AlertS
149+textToSeverity "Emergency" = Just EmergencyS
150+textToSeverity _ = Nothing
175151
176152
177153instance ToJSON Severity where
@@ -181,29 +157,14 @@ instance FromJSON Severity where
181157 parseJSON = A.withText "Severity" parseSeverity
182158 where
183159 parseSeverity t = case textToSeverity t of
184− Just x -> return x
160+ Just x -> return x
185161 Nothing -> fail $ "Invalid Severity " ++ toS t
186162
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−
202163
203164-------------------------------------------------------------------------------
204−-- | Log message with Builder underneath; use '<>' to concat in O(1).
165+-- | Log message with Builder unerneath; use '<>' to concat in O(1).
205166newtype LogStr = LogStr { unLogStr :: B.Builder }
206− deriving (Generic, Show, Eq)
167+ deriving (Generic, Show)
207168
208169instance IsString LogStr where
209170 fromString = LogStr . B.fromString
@@ -225,7 +186,7 @@ instance FromJSON LogStr where
225186
226187-------------------------------------------------------------------------------
227188-- | Pack any string-like thing into a 'LogStr'. This will
228−-- automatically work on 'String', 'ByteString', 'Text' and any of the
189+-- automatically work on 'String', 'ByteString, 'Text' and any of the
229190-- lazy variants.
230191logStr :: StringConv a Text => a -> LogStr
231192logStr t = LogStr (B.fromText $ toS t)
@@ -238,7 +199,7 @@ ls = logStr
238199
239200
240201-------------------------------------------------------------------------------
241−-- | Convert any showable type into a 'LogStr'.
202+-- | Convert any showable type into a LogStr.
242203showLS :: Show a => a -> LogStr
243204showLS = ls . show
244205
@@ -250,9 +211,7 @@ newtype ThreadIdText = ThreadIdText {
250211
251212
252213mkThreadIdText :: ThreadId -> ThreadIdText
253−mkThreadIdText = ThreadIdText . stripPrefix' "ThreadId " . T.pack . show
254− where
255− stripPrefix' pfx t = fromMaybe t (T.stripPrefix pfx t)
214+mkThreadIdText = ThreadIdText . T.pack . show
256215
257216
258217-------------------------------------------------------------------------------
@@ -272,62 +231,31 @@ data Item a = Item {
272231 } deriving (Generic, Functor)
273232makeLenses ''Item
274233
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− ]
298234
299235instance 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 <$> _itemLoc)
312− . showChar '}'
313− )
314− where
315− field n v = showString n . showString " = " . shows v . showString ", "
236+ show Item{..} = "Item {_itemApp = " ++ show _itemApp ++ ", " ++
237+ "_itemEnv = " ++ show _itemEnv ++ ", " ++
238+ "_itemSeverity = " ++ show _itemSeverity ++ ", " ++
239+ "_itemThread = " ++ show _itemThread ++ ", " ++
240+ "_itemHost = " ++ show _itemHost ++ ", " ++
241+ "_itemProcess = " ++ show _itemProcess ++ ", " ++
242+ "_itemPayload = " ++ show _itemPayload ++ ", " ++
243+ "_itemMessage = " ++ show _itemMessage ++ ", " ++
244+ "_itemTime = " ++ show _itemTime ++ ", " ++
245+ "_itemNamespace = " ++ show _itemNamespace ++ ", " ++
246+ "_itemLoc = " ++ show (LocShow <$> _itemLoc) ++ "}"
247+
316248
317249newtype LocShow = LocShow Loc
318250
319251
320252instance 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 ", "
253+ show (LocShow Loc{..}) =
254+ "Loc {loc_filename = " ++ show loc_filename ++ ", " ++
255+ "loc_package = " ++ show loc_package ++ ", " ++
256+ "loc_module = " ++ show loc_module ++ ", " ++
257+ "loc_start = " ++ show loc_start ++ ", " ++
258+ "loc_end = " ++ show loc_end ++ "}"
331259
332260
333261instance ToJSON a => ToJSON (Item a) where
@@ -408,7 +336,7 @@ instance FromJSON ProcessIDJs where
408336 parseJSON = A.withText "ProcessID" parseProcessID
409337 where
410338 parseProcessID t = case textToProcessID t of
411− Just p -> return $ ProcessIDJs p
339+ Just p -> return $ ProcessIDJs p
412340 Nothing -> fail $ "Invalid ProcessIDJs " ++ toS t
413341
414342
@@ -445,7 +373,7 @@ class ToObject a where
445373 default toObject :: ToJSON a => a -> A.Object
446374 toObject v = case toJSON v of
447375 A.Object o -> o
448− _ -> mempty
376+ _ -> mempty
449377
450378instance ToObject ()
451379instance ToObject A.Object
@@ -497,7 +425,7 @@ instance ToObject SimpleLogPayload
497425
498426instance LogItem SimpleLogPayload where
499427 payloadKeys V0 _ = SomeKeys []
500− payloadKeys _ _ = AllKeys
428+ payloadKeys _ _ = AllKeys
501429
502430
503431instance Semigroup SimpleLogPayload where
@@ -520,7 +448,7 @@ sl a b = SimpleLogPayload [(a, AnyLogPayload b)]
520448-- automatically bubble higher verbosity levels to lower ones.
521449payloadObject :: LogItem a => Verbosity -> a -> A.Object
522450payloadObject verb a = case FT.foldMap (flip payloadKeys a) [(V0)..verb] of
523− AllKeys -> toObject a
451+ AllKeys -> toObject a
524452 SomeKeys ks -> HM.filterWithKey (\ k _ -> k `FT.elem` ks) $ toObject a
525453
526454
@@ -540,107 +468,49 @@ itemJson verb a = toJSON $ a & itemPayload %~ payloadObject verb
540468--
541469-- Scribes should always take a 'Severity' and 'Verbosity'.
542470--
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.
471+-- Severity is used to *exclude log messages* that are < the provided
472+-- Severity. For instance, if the user passes InfoS, DebugS items
473+-- should be ignored. Katip provides the 'permitItem' utility for this.
549474--
550475-- Verbosity is used to select keys from the log item's payload. Each
551476-- 'LogItem' instance describes what keys should be retained for each
552477-- Verbosity level. Use the 'payloadObject' utility for extracting the keys
553−-- that should be written.
478+-- that should be permitted.
554479--
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.
480+-- There is no built-in mechanism in katip for telling a scribe that
481+-- its time to shut down. 'unregisterScribe' merely drops it from the
482+-- 'LogEnv'. This means there are 2 ways to handle resources as a scribe:
564483--
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)
484+-- 1. Pass in the resource when the scribe is created. Handle
485+-- allocation and release of the resource elsewhere. This is what the
486+-- Handle scribe does.
487+--
488+-- 2. Return a finalizing function that tells the scribe to shut
489+-- down. @katip-elasticsearch@'s @mkEsScribe@ returns a @IO (Scribe,
490+-- IO ())@. The finalizer will flush any queued log messages and shut
491+-- down gracefully before returning. This can be hooked into your
492+-- application's shutdown routine to ensure you never miss any log
493+-- messages on shutdown.
494+data Scribe = Scribe {
495+ liPush :: forall a. LogItem a => Item a -> IO ()
496+ }
586497
587498
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.
612499instance 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)
500+ (Scribe a) <> (Scribe b) = Scribe $ \ item -> do
501+ a item
502+ b item
619503
620504
621505instance Monoid Scribe where
622− mempty = Scribe (const (return ())) (return ()) (permitItem DebugS)
506+ mempty = Scribe $ const $ return ()
623507 mappend = (<>)
624508
625509
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−
639510-------------------------------------------------------------------------------
640511-- | 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)
512+permitItem :: Severity -> Item a -> Bool
513+permitItem sev i = _itemSeverity i >= sev
644514
645515
646516-------------------------------------------------------------------------------
@@ -659,16 +529,16 @@ data LogEnv = LogEnv {
659529 -- 'AutoUpdate' for high volume logs but note that this may cause
660530 -- some output forms to display logs out of order. Alternatively,
661531 -- you could just use 'getCurrentTime'.
662− , _logEnvScribes :: M.Map Text ScribeHandle
532+ , _logEnvScribes :: M.Map Text Scribe
663533 }
664534makeLenses ''LogEnv
665535
666536
667537-------------------------------------------------------------------------------
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'.
538+-- | Create a reasonable default InitLogEnv. Uses an 'AutoUdate' with
539+-- the default settings as the timer. If you are concerned about
540+-- timestamp precision or event ordering in log outputs like
541+-- ElasticSearch, you should replace the timer with 'getCurrentTime'
672542initLogEnv
673543 :: Namespace
674544 -- ^ A base namespace for this application
@@ -680,123 +550,45 @@ initLogEnv an env = LogEnv
680550 <*> getProcessID
681551 <*> pure an
682552 <*> pure env
683− <*> mkAutoUpdate defaultUpdateSettings { updateAction = getCurrentTime, updateFreq = 1000 }
553+ <*> mkAutoUpdate defaultUpdateSettings { updateAction = getCurrentTime }
684554 <*> pure mempty
685555
686556
687557-------------------------------------------------------------------------------
688558-- | 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.
559+-- scribe in addition to the others.
692560registerScribe
693561 :: Text
694562 -- ^ Name the scribe
695563 -> Scribe
696− -> ScribeSettings
697564 -> 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
565+ -> LogEnv
566+registerScribe nm h = logEnvScribes %~ M.insert nm h
741567
742568
743569-------------------------------------------------------------------------------
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.
570+-- | Remove a scribe from the list. All future log calls will no
571+-- longer use this scribe. If the given scribe doesn't exist, its a no-op.
748572unregisterScribe
749573 :: Text
750574 -- ^ Name of the scribe
751575 -> LogEnv
752576 -> LogEnv
753−unregisterScribe nm = logEnvScribes %~ M.delete nm
577+unregisterScribe nm = logEnvScribes %~ M.delete nm
754578
755579
756580-------------------------------------------------------------------------------
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.
581+-- | Unregister *all* scribes. Logs will go off into space from this
582+-- point onward until new scribes are added. Note that you could use
583+-- this with `local` if you're using a Reader based stack to
584+-- temporarily disable log output. See `katipNoLogging` for an
585+-- example.
761586clearScribes
762587 :: LogEnv
763588 -> LogEnv
764589clearScribes = logEnvScribes .~ mempty
765590
766591
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−
800592-------------------------------------------------------------------------------
801593-- | Monads where katip logging actions can be performed. Katip is the
802594-- most basic logging monad. You will typically use this directly if
@@ -807,86 +599,44 @@ closeScribes le = do
807599-- which keeps a namespace and merged context. You can write simple
808600-- functions that add additional namespacing and merges additional
809601-- 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.
815602class MonadIO m => Katip m where
816603 getLogEnv :: m LogEnv
817− localLogEnv :: (LogEnv -> LogEnv) -> m a -> m a
818604
819605
820606instance Katip m => Katip (ReaderT s m) where
821607 getLogEnv = lift getLogEnv
822− localLogEnv = mapReaderT . localLogEnv
823608
824609
825−#if !MIN_VERSION_either(4, 5, 0)
826610instance Katip m => Katip (EitherT s m) where
827611 getLogEnv = lift getLogEnv
828− localLogEnv = mapEitherT . localLogEnv
829−#endif
830−
831612
832613instance Katip m => Katip (ExceptT s m) where
833614 getLogEnv = lift getLogEnv
834− localLogEnv = mapExceptT . localLogEnv
835−
836615
837616instance Katip m => Katip (MaybeT m) where
838617 getLogEnv = lift getLogEnv
839− localLogEnv = mapMaybeT . localLogEnv
840618
841619
842620instance Katip m => Katip (StateT s m) where
843621 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
860622
861623
862624instance (Katip m, Monoid s) => Katip (WriterT s m) where
863625 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−
871626
872627instance (Katip m) => Katip (ResourceT m) where
873628 getLogEnv = lift getLogEnv
874− localLogEnv = transResourceT . localLogEnv
875629
876630
877631-------------------------------------------------------------------------------
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.
632+-- | A concrete monad you can use to run logging actions.
881633newtype KatipT m a = KatipT { unKatipT :: ReaderT LogEnv m a }
882634 deriving ( Functor, Applicative, Monad, MonadIO
883− , MonadMask, MonadCatch, MonadThrow, MonadResource, MonadTrans
884− , MonadBase b)
635+ , MonadMask, MonadCatch, MonadThrow, MonadTrans, MonadBase b)
885636
886637
887638instance MonadIO m => Katip (KatipT m) where
888639 getLogEnv = KatipT ask
889− localLogEnv f (KatipT m) = KatipT $ local f m
890640
891641
892642instance MonadTransControl KatipT where
@@ -902,21 +652,6 @@ instance (MonadBaseControl b m) => MonadBaseControl b (KatipT m) where
902652 liftBaseWith = defaultLiftBaseWith
903653 restoreM = defaultRestoreM
904654
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
920655
921656-------------------------------------------------------------------------------
922657-- | Execute 'KatipT' on a log env.
@@ -924,17 +659,6 @@ runKatipT :: LogEnv -> KatipT m a -> m a
924659runKatipT le (KatipT f) = runReaderT f le
925660
926661
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−
938662-------------------------------------------------------------------------------
939663-- | Log with everything, including a source code location. This is
940664-- very low level and you typically can use 'logT' in its place.
@@ -948,43 +672,20 @@ logItem
948672 -> m ()
949673logItem a ns loc sev msg = do
950674 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)
675+ liftIO $ do
676+ item <- Item
677+ <$> pure _logEnvApp
678+ <*> pure _logEnvEnv
679+ <*> pure sev
680+ <*> (mkThreadIdText <$> myThreadId)
681+ <*> pure _logEnvHost
682+ <*> pure _logEnvPid
683+ <*> pure a
684+ <*> pure msg
685+ <*> _logEnvTimer
686+ <*> pure (_logEnvApp <> ns)
687+ <*> pure loc
688+ FT.forM_ (M.elems _logEnvScribes) $ \ (Scribe h) -> h item
988689
989690
990691-------------------------------------------------------------------------------
@@ -1016,10 +717,10 @@ logException
1016717 -> Severity -- ^ Severity
1017718 -> m b -- ^ Main action being run
1018719 -> m b
1019−logException a ns sev action = action `catchAny` \e -> f e >> throwM e
720+logException a ns sev action = action `catchAll` \e -> f e >> throwM e
1020721 where
1021722 f e = logF a ns sev (msg e)
1022− msg e = ls (T.pack "An exception has occurred: ") <> showLS e
723+ msg e = ls (T.pack "An exception has occured: ") <> showLS e
1023724
1024725
1025726-------------------------------------------------------------------------------
@@ -1047,14 +748,14 @@ instance TH.Lift Verbosity where
1047748
1048749
1049750instance TH.Lift Severity where
1050− lift DebugS = [| DebugS |]
1051− lift InfoS = [| InfoS |]
1052− lift NoticeS = [| NoticeS |]
1053− lift WarningS = [| WarningS |]
1054− lift ErrorS = [| ErrorS |]
751+ lift DebugS = [| DebugS |]
752+ lift InfoS = [| InfoS |]
753+ lift NoticeS = [| NoticeS |]
754+ lift WarningS = [| WarningS |]
755+ lift ErrorS = [| ErrorS |]
1055756 lift CriticalS = [| CriticalS |]
1056− lift AlertS = [| AlertS |]
1057− lift EmergencyS = [| EmergencyS |]
757+ lift AlertS = [| AlertS |]
758+ lift EmergencyS = [| EmergencyS |]
1058759
1059760
1060761-- | Lift a location into an Exp.
@@ -1073,15 +774,11 @@ liftLoc (Loc a b c (d1, d2) (e1, e2)) = [|Loc
1073774-- fill the 'Maybe Loc' gap in 'logF' of this module, and relies on implicit
1074775-- callstacks when available (GHC > 7.8).
1075776#if MIN_VERSION_base(4, 8, 0)
1076−getLoc :: HasCallStack => Maybe Loc
1077−getLoc = case getCallStack callStack of
777+getLoc :: (?loc :: CallStack) => Maybe Loc
778+getLoc = case getCallStack ?loc of
1078779 [] -> Nothing
1079− xs -> Just . toLoc . head $ filter filterKatip xs
780+ xs -> Just . toLoc . last $ xs
1080781 where
1081− filterKatip :: (String, SrcLoc) -> Bool
1082− filterKatip (_, srcloc) = not $
1083− "katip-" `isPrefixOf` srcLocPackage srcloc
1084−
1085782 toLoc :: (String, SrcLoc) -> Loc
1086783 toLoc (_, l) = Loc {
1087784 loc_filename = srcLocFile l
@@ -1112,7 +809,7 @@ logT = [| \ a ns sev msg -> logItem a ns (Just $(getLocTH)) sev msg |]
1112809
1113810
1114811-------------------------------------------------------------------------------
1115−-- | 'Loc'-tagged logging using 'GHC.Stack' when available.
812+-- | 'Loc'-tagged logging using implicit-callstacks when available.
1116813--
1117814-- This function does not require template-haskell as it
1118815-- automatically uses <https://hackage.haskell.org/package/base-4.8.2.0/docs/GHC-Stack.html#v:getCallStack implicit-callstacks>
@@ -1122,11 +819,7 @@ logT = [| \ a ns sev msg -> logItem a ns (Just $(getLocTH)) sev msg |]
1122819-- `logT` for maximum compatibility.
1123820--
1124821-- @logLoc obj mempty InfoS "Hello world"@
1125−#if MIN_VERSION_base(4, 8, 0)
1126−logLoc :: (Applicative m, LogItem a, Katip m, HasCallStack)
1127−#else
1128822logLoc :: (Applicative m, LogItem a, Katip m)
1129−#endif
1130823 => a
1131824 -> Namespace
1132825 -> Severity