packages feed

log-warper (empty) → 0.2.1

raw patch · 14 files changed

+1527/−0 lines, 14 filesdep +aesondep +ansi-terminaldep +basesetup-changed

Dependencies added: aeson, ansi-terminal, base, bytestring, data-default, directory, dlist, errors, exceptions, extra, filepath, formatting, hashable, hslogger, lens, log-warper, monad-control, mtl, safecopy, text, text-format, time, transformers, transformers-base, unordered-containers, yaml

Files

+ LICENSE view
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+ Setup.hs view
@@ -0,0 +1,2 @@+import Distribution.Simple+main = defaultMain
+ examples/Playground.hs view
@@ -0,0 +1,40 @@+-- | Testing module to play with logging.++module Main where++import           Control.Exception (bracket_)++import           Data.Monoid       ((<>))+import qualified Data.Text         as T (pack)++import           System.Wlog       (CanLog, dispatchEvents, initLoggingFromYaml, logDebug,+                                    logError, logInfo, logNotice, logWarning,+                                    modifyLoggerName, releaseAllHandlers, runPureLog,+                                    usingLoggerName)++testLogging :: CanLog m => m ()+testLogging = usingLoggerName "node" $ do+    logDebug   "skovoroda"+    logInfo    "patak"+    logNotice  "boroda"+    logWarning "haha"++    modifyLoggerName (<> "server") $ do+        logDebug  "provoda"+        logNotice "Ggurda"++    logError   "BARDAQ"++showPureLog :: IO ()+showPureLog = do+    (res, pureLog) <- runPureLog testLogging+    putStrLn "Pure log:"+    usingLoggerName "naked" $ do+        logWarning $ "Pure log for result = " <> (T.pack $ show res) <> ":"+        dispatchEvents pureLog++main :: IO ()+main = bracket_+           (initLoggingFromYaml "logger-config-example.yaml" $ Just "logs")+           releaseAllHandlers+           (testLogging >> showPureLog)
+ log-warper.cabal view
@@ -0,0 +1,91 @@+name:                log-warper+version:             0.2.1+synopsis:            Flexible, configurable, monadic and pretty logging+homepage:            https://github.com/serokell/log-warper+license:             GPL-3+license-file:        LICENSE+author:              Serokell team+maintainer:          Serokell <hi@serokell.io>+copyright:           2016-2016 Serokell+category:            Interfaces+build-type:          Simple+cabal-version:       >=1.18+description:+    This package contains nice wrapper around hslogger library.++Flag PatakDebugSkovorodaBARDAQ+    default:     False+    description: Enable debug support++library+  exposed-modules:     System.Wlog+                       System.Wlog.CanLog+                       System.Wlog.LoggerConfig+                       System.Wlog.LoggerName+                       System.Wlog.LoggerNameBox+                       System.Wlog.Parser+                       System.Wlog.Severity+                       System.Wlog.Wrapper++  other-modules:       System.Wlog.Color+                       System.Wlog.Formatter++  build-depends:       aeson                >= 0.11.2.1+                     , ansi-terminal        >= 0.6.2.3+                     , base                 >= 4.7 && < 5+                     , bytestring           >= 0.10.8.1+                     , data-default         >= 0.7.1+                     , directory            >= 1.2.6.2+                     , dlist                >= 0.8.0.2+                     , errors               >= 2.1.2+                     , exceptions           >= 0.8.3+                     , extra                >= 1.4.10+                     , filepath             >= 1.4.1+                     , formatting           >= 6.2.2+                     , hashable             >= 1.2.4.0+                     , hslogger             >= 1.2.10+                     , lens                 >= 4.14+                     , monad-control        >= 1.0.1.0+                     , mtl                  >= 2.2.1+                     , safecopy             >= 0.9.1+                     , text                 >= 1.2.2.0+                     , text-format          >= 0.3.1.1+                     , time                 >= 1.6.0.1+                     , transformers         >= 0.5.2+                     , transformers-base    >= 0.4.4+                     , unordered-containers >= 0.2.7.1+                     , yaml                 >= 0.8.20++  hs-source-dirs:      src+  default-language:    Haskell2010+  ghc-options:         -Wall -fno-warn-orphans -fprint-potential-instances++  default-extensions:  GeneralizedNewtypeDeriving+                       DeriveDataTypeable+                       DeriveGeneric+                       OverloadedStrings+                       TypeApplications+                       RecordWildCards++  if flag(PatakDebugSkovorodaBARDAQ)+      cpp-options:     -DPatakDebugSkovorodaBARDAQ++executable play-log+  main-is:             Playground.hs++  build-depends:       base       >= 4.7 && < 5+                     , exceptions >= 0.8.2.1+                     , hslogger   >= 1.2.10+                     , log-warper+                     , text       >= 1.2.2.1++  hs-source-dirs:      examples+  default-language:    Haskell2010+  ghc-options:         -threaded -Wall -fno-warn-orphans++  default-extensions:  GeneralizedNewtypeDeriving+                       DeriveDataTypeable+                       DeriveGeneric+                       OverloadedStrings+                       TypeApplications+                       RecordWildCards
+ src/System/Wlog.hs view
@@ -0,0 +1,30 @@+-- |+-- Module      : System.Wlog+-- Copyright   : (c) Serokell, 2016+-- License     : GPL-3 (see the file LICENSE)+-- Maintainer  : Serokell <hi@serokell.io>+-- Stability   : experimental+-- Portability : POSIX, GHC+--+-- Logging functionality. This module is wrapper over+-- <http://hackage.haskell.org/package/hslogger hslogger>,+-- which allows to keep logger name in monadic context.+-- Messages are colored depending on used serverity.++module System.Wlog+       ( module System.Wlog.CanLog+       , module System.Wlog.LoggerConfig+       , module System.Wlog.LoggerName+       , module System.Wlog.LoggerNameBox+       , module System.Wlog.Parser+       , module System.Wlog.Severity+       , module System.Wlog.Wrapper+       ) where++import           System.Wlog.CanLog+import           System.Wlog.LoggerConfig+import           System.Wlog.LoggerName+import           System.Wlog.LoggerNameBox+import           System.Wlog.Parser+import           System.Wlog.Severity+import           System.Wlog.Wrapper
+ src/System/Wlog/CanLog.hs view
@@ -0,0 +1,133 @@+{-# LANGUAGE ConstraintKinds       #-}+{-# LANGUAGE DefaultSignatures     #-}+{-# LANGUAGE FlexibleInstances     #-}+{-# LANGUAGE MultiParamTypeClasses #-}+{-# LANGUAGE OverloadedLists       #-}+{-# LANGUAGE TemplateHaskell       #-}+{-# LANGUAGE TypeFamilies          #-}+{-# LANGUAGE UndecidableInstances  #-}+{-# LANGUAGE ViewPatterns          #-}++-- | Type class that add ability to log messages.+-- Supports pure and IO logging.++module System.Wlog.CanLog+       ( CanLog (..)+       , WithLogger++         -- * Pure logging manipulation+       , PureLogger (..)+       , LogEvent   (..)+       , dispatchEvents+       , runPureLog++         -- * Logging functions+       , logDebug+       , logError+       , logInfo+       , logNotice+       , logWarning+       , logMessage+       ) where++import           Control.Monad.Reader      (MonadReader, ReaderT)+import           Control.Monad.State       (MonadState, StateT)+import           Control.Monad.Trans       (MonadTrans (lift))+import           Control.Monad.Writer      (MonadWriter (tell), WriterT (runWriterT))++import           Data.Bifunctor            (second)+import           Data.DList                (DList, toList)+import           Data.SafeCopy             (base, deriveSafeCopySimple)+import           Data.Text                 (Text)+import qualified Data.Text                 as T++import           System.Log.Logger         (logM)++import           System.Wlog.LoggerName    (LoggerName (..))+import           System.Wlog.LoggerNameBox (HasLoggerName (..), LoggerNameBox (..))+import           System.Wlog.Severity      (Severity (..), convertSeverity)++-- | Type alias for constraints 'CanLog' and 'HasLoggerName'.+-- We need two different type classes to support more flexible interface+-- but in practice we usually use them both.+type WithLogger m = (CanLog m, HasLoggerName m)++-- | Instances of this class should explain how they add messages to their log.+class Monad m => CanLog m where+    dispatchMessage :: LoggerName -> Severity -> Text -> m ()++    -- Redundant constraint here due to type checker regressing in ghc-8.0.2-rc1+    -- https://ghc.haskell.org/trac/ghc/ticket/12784+    default dispatchMessage :: (MonadTrans t, t n ~ m, CanLog n)+                            => LoggerName+                            -> Severity+                            -> Text+                            -> t n ()+    dispatchMessage name sev t = lift $ dispatchMessage name sev t++instance CanLog IO where+    dispatchMessage+        (loggerName      -> name)+        (convertSeverity -> prior)+        (T.unpack        -> t)+      = logM name prior t++instance CanLog m => CanLog (LoggerNameBox m)+instance CanLog m => CanLog (ReaderT r m)+instance CanLog m => CanLog (StateT s m)++-- | Holds all required information for 'dispatchLoggerName' function.+data LogEvent = LogEvent+    { leLoggerName :: !LoggerName+    , leSeverity   :: !Severity+    , leMessage    :: !Text+    } deriving (Show)++deriveSafeCopySimple 0 'base ''LogEvent++-- | Pure implementation of 'CanLog' type class. Instead of writing log messages+-- into console it appends log messages into 'WriterT' log. It uses 'DList' for+-- better performance, because messages can be added only at the end of log.+-- But it uses 'unsafePerformIO' so use with caution within IO.+--+-- TODO: Should we use some @Data.Tree@-like structure to observe message only+-- by chosen loger names?+newtype PureLogger m a = PureLogger+    { runPureLogger :: WriterT (DList LogEvent) m a+    } deriving (Functor, Applicative, Monad, MonadTrans, MonadWriter (DList LogEvent),+                MonadState s, MonadReader r, HasLoggerName)++instance Monad m => CanLog (PureLogger m) where+    dispatchMessage leLoggerName leSeverity leMessage = tell [LogEvent{..}]++-- | Return log of pure logging action as list of 'LogEvent'.+runPureLog :: Monad m => PureLogger m a -> m (a, [LogEvent])+runPureLog = fmap (second toList) . runWriterT . runPureLogger++-- | Logs all 'LogEvent'`s from given list. This function supposed to+-- be used after 'runPureLog'.+dispatchEvents :: WithLogger m => [LogEvent] -> m ()+dispatchEvents = mapM_ dispatchLogEvent+  where+    dispatchLogEvent (LogEvent name sev t) = dispatchMessage name sev t++-- | Shortcut for 'logMessage' to use according severity.+logDebug, logInfo, logNotice, logWarning, logError+    :: WithLogger m+    => Text+    -> m ()+logDebug   = logMessage Debug+logInfo    = logMessage Info+logNotice  = logMessage Notice+logWarning = logMessage Warning+logError   = logMessage Error++-- | Logs message with specified severity using logger name in context.+logMessage+    :: WithLogger m+    => Severity+    -> Text+    -> m ()+logMessage severity t = do+    name <- getLoggerName+    dispatchMessage name severity t
+ src/System/Wlog/Color.hs view
@@ -0,0 +1,39 @@+-- |+-- Module      : System.Wlog.Color+-- Copyright   : (c) Serokell, 2016+-- License     : GPL-3 (see the file LICENSE)+-- Maintainer  : Serokell <hi@serokell.io>+-- Stability   : experimental+-- Portability : POSIX, GHC+--+-- Colorizing utilities for log messages.+-- Messages are colored depending on used serverity.++module System.Wlog.Color+       ( colorizer+       ) where++import           System.Console.ANSI (Color (Blue, Green, Magenta, Red, Yellow),+                                      ColorIntensity (Vivid), ConsoleLayer (Foreground),+                                      SGR (Reset, SetColor), setSGRCode)++import           System.Log.Logger   (Priority (DEBUG, ERROR, INFO, NOTICE, WARNING))++-- | Defines pre- and post-printed characters for printing colorized text.+table :: Priority -> (String, String)+table priority = case priority of+    ERROR   -> (setColor Red     , reset)+    DEBUG   -> (setColor Green   , reset)+    NOTICE  -> (setColor Magenta , reset)+    WARNING -> (setColor Yellow  , reset)+    INFO    -> (setColor Blue    , reset)+    _       -> ("", "")+  where+    setColor color = setSGRCode [SetColor Foreground Vivid color]+    reset = setSGRCode [Reset]++-- | Colorizes text.+colorizer :: Priority -> String -> String+colorizer pr s = before ++ s ++ after+  where+    (before, after) = table pr
+ src/System/Wlog/Formatter.hs view
@@ -0,0 +1,63 @@+-- |+-- Module      : System.Wlog.Formatter+-- Copyright   : (c) Serokell, 2016+-- License     : GPL-3 (see the file LICENSE)+-- Maintainer  : Serokell <hi@serokell.io>+-- Stability   : experimental+-- Portability : POSIX, GHC+--+-- This module contains pretty looking formatters for logger.++module System.Wlog.Formatter+       ( formatLogMessage+       , setStderrFormatter+       , setStdoutFormatter+       ) where++import           Data.Monoid            (mconcat)+import           Data.String            (IsString)+import           Data.Text              (Text)+import           Data.Time.Clock        (UTCTime)+import           Formatting             (Format, sformat, shown, stext, (%))++import           System.Log.Formatter   (LogFormatter, simpleLogFormatter)+import           System.Log.Handler     (LogHandler (setFormatter))+import           System.Log.Logger      (Priority (ERROR))++import           System.Wlog.Color      (colorizer)+import           System.Wlog.LoggerName (LoggerName, loggerNameF)+import           System.Wlog.Severity   (Severity)++timeFmt :: IsString s => s+timeFmt = "[$time] "++timeFmtStdout :: IsString s => Bool -> s+timeFmtStdout isShowTime = if isShowTime+                           then timeFmt+                           else ""++stderrFormatter :: LogFormatter a+stderrFormatter =+    simpleLogFormatter $+        mconcat [colorizer ERROR "[$loggername:$prio] ", timeFmt, "$msg"]++stdoutFmt :: Priority -> Bool -> String+stdoutFmt pr isShowTime = mconcat+    [colorizer pr "[$loggername:$prio] ", timeFmtStdout isShowTime, "$msg"]++stdoutFormatter :: Bool -> LogFormatter a+stdoutFormatter isShowTime handle r@(pr, _) =+    simpleLogFormatter (stdoutFmt pr isShowTime) handle r++setStdoutFormatter :: LogHandler h => Bool -> h -> h+setStdoutFormatter isShowTime = (`setFormatter` stdoutFormatter isShowTime)++setStderrFormatter :: LogHandler h => h -> h+setStderrFormatter = (`setFormatter` stderrFormatter)++-- TODO: do we need coloring here?+formatLogMessage :: LoggerName -> Severity -> UTCTime -> Text -> Text+formatLogMessage = sformat ("["%loggerNameF%":"%shown%"] ["%utcTimeF%"] "%stext)+  where+    utcTimeF :: Format r (UTCTime -> r)+    utcTimeF = shown
+ src/System/Wlog/LoggerConfig.hs view
@@ -0,0 +1,55 @@+-- |+-- Module      : System.Wlog.LoggerConfig+-- Copyright   : (c) Serokell, 2016+-- License     : GPL-3 (see the file LICENSE)+-- Maintainer  : Serokell <hi@serokell.io>+-- Stability   : experimental+-- Portability : POSIX, GHC+--+-- Logger configuration.++module System.Wlog.LoggerConfig+       ( LoggerConfig (..)+       , LoggerMap+       ) where++import           Data.Aeson          (withObject)+import           Data.Default        (Default (def))+import           Data.HashMap.Strict (HashMap)+import qualified Data.HashMap.Strict as HM hiding (HashMap)+import           Data.Text           (Text)+import           Data.Traversable    (for)+import           Data.Yaml           (FromJSON (..), ToJSON, (.:?))+import           GHC.Generics        (Generic)++import           System.Wlog.Wrapper (Severity)++type LoggerMap = HashMap Text LoggerConfig++data LoggerConfig = LoggerConfig+    { lcSubloggers :: !LoggerMap+    , lcFile       :: !(Maybe FilePath)+    , lcSeverity   :: !(Maybe Severity)+    } deriving (Generic, Show)++instance ToJSON LoggerConfig++instance Default LoggerConfig where+    def = LoggerConfig+          { lcFile       = Nothing+          , lcSeverity   = Nothing+          , lcSubloggers = mempty+          }++nonLoggers :: [Text]+nonLoggers = ["file", "severity"]++selectLoggers :: HashMap Text a -> HashMap Text a+selectLoggers = HM.filterWithKey $ \k _ -> k `notElem` nonLoggers++instance FromJSON LoggerConfig where+    parseJSON = withObject "root loggers" $ \o -> do+        lcFile       <- o .:? "file"+        lcSeverity   <- o .:? "severity"+        lcSubloggers <- for (selectLoggers o) parseJSON+        return LoggerConfig{..}
+ src/System/Wlog/LoggerName.hs view
@@ -0,0 +1,46 @@+{-# LANGUAGE TemplateHaskell #-}++-- | Contains @newtype@ wrapper around logger name to support hierarchy.++module System.Wlog.LoggerName+       ( LoggerName (..)+       , loggerNameF+       ) where++import           Data.Hashable       (Hashable)+import           Data.SafeCopy       (base, deriveSafeCopySimple)+import           Data.Semigroup      (Semigroup)+import qualified Data.Semigroup      as Semigroup+import           Data.String         (IsString)+import           Data.Text.Buildable (Buildable)+import qualified Data.Text.Buildable as Buildable+import           Formatting          (Format, bprint, build, string)++-- | Logger name to keep in context.++-- TODO: replace 'String' with 'Text'+-- TODO: change field name into @getLoggerName@ to follow naming convention+newtype LoggerName = LoggerName+    { loggerName :: String+    } deriving (Show, IsString, Eq, Hashable)++deriveSafeCopySimple 0 'base ''LoggerName++-- | Defined such that @n1@ is parent for @(n1 <> n2)@+-- (see <http://hackage.haskell.org/package/hslogger-1.2.10/docs/System-Log-Logger.html hslogger description>).+instance Semigroup LoggerName where+    LoggerName parent <> LoggerName suffix+        | null parent = LoggerName suffix+        | null suffix = LoggerName parent+        | otherwise   = LoggerName $ parent ++ "." ++ suffix++instance Monoid LoggerName where+    mempty = ""+    mappend = (Semigroup.<>)++instance Buildable LoggerName where+    build = bprint string . loggerName++-- | 'LoggerName' formatter which restricts type.+loggerNameF :: Format r (LoggerName -> r)+loggerNameF = build
+ src/System/Wlog/LoggerNameBox.hs view
@@ -0,0 +1,97 @@+{-# LANGUAGE FlexibleInstances     #-}+{-# LANGUAGE MultiParamTypeClasses #-}+{-# LANGUAGE TypeFamilies          #-}+{-# LANGUAGE UndecidableInstances  #-}++-- | This module contains type classes for loggers that have 'LoggerName'.++module System.Wlog.LoggerNameBox+       ( -- * Remove boilerplater+         HasLoggerName (..)+       , LoggerNameBox (..)+       , setLoggerName+       , usingLoggerName+       ) where++import           Control.Monad.Base          (MonadBase)+import           Control.Monad.Catch         (MonadCatch, MonadMask, MonadThrow)+import           Control.Monad.Except        (ExceptT (..), runExceptT)+import           Control.Monad.Fix           (MonadFix)+import           Control.Monad.Reader        (MonadReader (..), ReaderT, runReaderT)+import           Control.Monad.State         (MonadState (get), StateT, evalStateT)+import           Control.Monad.Trans         (MonadIO, MonadTrans, lift)+import           Control.Monad.Trans.Cont    (ContT, mapContT)+import           Control.Monad.Trans.Control (MonadBaseControl (..))+import           Control.Monad.Writer        (WriterT (..))++import           System.Wlog.LoggerName      (LoggerName)++-- | This type class exists to remove boilerplate logging+-- by adding the logger's name to the context in each module.+--+-- TODO: replace current methods with Lens?+class HasLoggerName m where+    -- | Extract logger name from context+    getLoggerName :: m LoggerName++    -- | Change logger name in context+    modifyLoggerName :: (LoggerName -> LoggerName) -> m a -> m a+++instance (Monad m, HasLoggerName m) => HasLoggerName (ReaderT a m) where+    getLoggerName = lift getLoggerName++    modifyLoggerName how m =+        ask >>= lift . modifyLoggerName how . runReaderT m++instance (Monad m, HasLoggerName m) => HasLoggerName (StateT a m) where+    getLoggerName = lift getLoggerName++    modifyLoggerName how m =+        get >>= lift . modifyLoggerName how . evalStateT m++instance (Monoid w, Monad m, HasLoggerName m) => HasLoggerName (WriterT w m) where+    getLoggerName = lift getLoggerName++    modifyLoggerName how = WriterT . modifyLoggerName how . runWriterT++instance (Monad m, HasLoggerName m) => HasLoggerName (ExceptT e m) where+    getLoggerName = lift getLoggerName++    modifyLoggerName how = ExceptT . modifyLoggerName how . runExceptT++instance (Monad m, HasLoggerName m) => HasLoggerName (ContT r m) where+    getLoggerName = lift getLoggerName++    modifyLoggerName = mapContT . modifyLoggerName++-- | Set logger name in context.+setLoggerName :: HasLoggerName m => LoggerName -> m a -> m a+setLoggerName = modifyLoggerName . const++-- | Default implementation of `WithNamedLogger`.+newtype LoggerNameBox m a = LoggerNameBox+    { loggerNameBoxEntry :: ReaderT LoggerName m a+    } deriving (Functor, Applicative, Monad, MonadIO, MonadTrans, MonadBase b,+                MonadThrow, MonadCatch, MonadMask, MonadState s, MonadFix)+++instance MonadReader r m => MonadReader r (LoggerNameBox m) where+    ask = lift ask+    reader = lift . reader+    local f (LoggerNameBox m) = getLoggerName >>= lift . local f . runReaderT m++instance MonadBaseControl b m => MonadBaseControl b (LoggerNameBox m) where+    type StM (LoggerNameBox m) a = StM (ReaderT LoggerName m) a+    liftBaseWith io =+        LoggerNameBox $ liftBaseWith $ \runInBase -> io $ runInBase . loggerNameBoxEntry+    restoreM = LoggerNameBox . restoreM++-- | Runs a `LoggerNameBox` with specified initial `LoggerName`.+usingLoggerName :: LoggerName -> LoggerNameBox m a -> m a+usingLoggerName name = flip runReaderT name . loggerNameBoxEntry++instance Monad m => HasLoggerName (LoggerNameBox m) where+    getLoggerName = LoggerNameBox ask++    modifyLoggerName how = LoggerNameBox . local how . loggerNameBoxEntry
+ src/System/Wlog/Parser.hs view
@@ -0,0 +1,112 @@+{-# LANGUAGE CPP          #-}+{-# LANGUAGE ViewPatterns #-}++-- |+-- Module      : System.Wlog.Parser+-- Copyright   : (c) Serokell, 2016+-- License     : GPL-3 (see the file LICENSE)+-- Maintainer  : Serokell <hi@serokell.io>+-- Stability   : experimental+-- Portability : POSIX, GHC+--+-- Parser for configuring and initializing logger from YAML file.+-- Logger configuration should look like this:+--+-- > node:                    # logger named «node»+-- >     severity: Warning    # severity for logger «node»+-- >     comm:                # logger named «node.comm»+-- >         severity: Info   # severity for logger «node.comm»+-- >         file: patak.jpg  # messages will be also printed to patak.jpg+--+-- And this configuration corresponds two loggers with 'LoggerName'`s+-- @node@ and @node.comm@.++module System.Wlog.Parser+       ( initLoggingFromYaml+       , initLoggingFromYamlWithMapper+       , parseLoggerConfig+       , traverseLoggerConfig+       ) where++#if PatakDebugSkovorodaBARDAQ+import qualified Data.ByteString.Char8     as BS (putStrLn)+import           Data.Yaml.Pretty          (defConfig, encodePretty)+#endif++import           Control.Error.Util        ((?:))+import           Control.Exception         (throwIO)+import           Control.Monad             (join)+import           Control.Monad.Extra       (whenJust)+import           Control.Monad.IO.Class    (MonadIO (liftIO))++import           Data.Foldable             (for_)+import qualified Data.HashMap.Strict       as HM hiding (HashMap)+import           Data.Maybe                (fromMaybe)+import           Data.Monoid               ((<>))+import           Data.Text                 (unpack)+import           Data.Yaml                 (decodeFileEither)++import           System.Directory          (createDirectoryIfMissing)+import           System.FilePath           ((</>))+import           System.Log.Handler.Simple (fileHandler)+import           System.Log.Logger         (addHandler, updateGlobalLogger)++import           System.Wlog.Formatter     (setStdoutFormatter)+import           System.Wlog.LoggerConfig  (LoggerConfig (..))+import           System.Wlog.LoggerName    (LoggerName (..))+import           System.Wlog.Wrapper       (Severity (Debug, Warning), convertSeverity,+                                            initLogging, setSeverityMaybe)++-- | This function traverses 'LoggerConfig' initializing all subloggers+-- with 'Severity' and redirecting output in file handlers. Also takes+-- 'FilePath' prefix to create directory for file handlers output.+traverseLoggerConfig+    :: MonadIO m+    => (LoggerName -> LoggerName)  -- ^ mapper to transform logger names during traversal+    -> LoggerConfig                -- ^ given LoggerConfig to traverse+    -> Maybe FilePath              -- ^ prefix for file handlers+    -> m ()+traverseLoggerConfig logMapper config (fromMaybe "." -> handlerPrefix) = do+    liftIO $ createDirectoryIfMissing True handlerPrefix+    initLogging Warning+    processLoggers mempty config+  where+    processLoggers:: MonadIO m => LoggerName -> LoggerConfig -> m ()+    processLoggers parent LoggerConfig{..} = do+        setSeverityMaybe parent lcSeverity++        whenJust lcFile $ \fileName -> liftIO $ do+            let fileSeverity   = convertSeverity $ lcSeverity ?: Debug+            let handlerPath    = handlerPrefix </> fileName+            thisLoggerHandler <- setStdoutFormatter True <$> fileHandler handlerPath fileSeverity+            updateGlobalLogger (loggerName parent) $ addHandler thisLoggerHandler++        for_ (HM.toList lcSubloggers) $ \(name, loggerConfig) -> do+            let thisLoggerName = LoggerName $ unpack name+            let thisLogger     = parent <> logMapper thisLoggerName+            processLoggers thisLogger loggerConfig++-- | Parses logger config from given file path.+parseLoggerConfig :: MonadIO m => FilePath -> m LoggerConfig+parseLoggerConfig loggerConfigPath =+    liftIO $ join $ either throwIO return <$> decodeFileEither loggerConfigPath++-- | Initialize logger hierarchy from configuration file.+-- See this module description.+initLoggingFromYamlWithMapper+    :: MonadIO m+    => (LoggerName -> LoggerName)+    -> FilePath+    -> Maybe FilePath+    -> m ()+initLoggingFromYamlWithMapper loggerMapper loggerConfigPath handlerPrefix = do+    loggerConfig <- parseLoggerConfig loggerConfigPath++#if PatakDebugSkovorodaBARDAQ+    liftIO $ BS.putStrLn $ encodePretty defConfig loggerConfig+#endif++    traverseLoggerConfig loggerMapper loggerConfig handlerPrefix++initLoggingFromYaml :: MonadIO m => FilePath -> Maybe FilePath -> m ()+initLoggingFromYaml = initLoggingFromYamlWithMapper id
+ src/System/Wlog/Severity.hs view
@@ -0,0 +1,36 @@+{-# LANGUAGE TemplateHaskell #-}++-- | Custom wrapper around @hslogger.Priority@.++module System.Wlog.Severity+       ( Severity (..)+       , convertSeverity+       ) where++import           Data.SafeCopy     (base, deriveSafeCopySimple)+import           Data.Typeable     (Typeable)+import           Data.Yaml         (FromJSON, ToJSON)+import           GHC.Generics      (Generic)+import           System.Log.Logger (Priority (DEBUG, ERROR, INFO, NOTICE, WARNING))++-- | This type specifies which messages to print.+data Severity+    = Debug+    | Info+    | Notice+    | Warning+    | Error+    deriving (Generic, Typeable, Show, Read, Eq)++instance FromJSON Severity+instance ToJSON   Severity++deriveSafeCopySimple 0 'base ''Severity++-- | Maps 'Severity' into 'Priority'.+convertSeverity :: Severity -> Priority+convertSeverity Debug   = DEBUG+convertSeverity Info    = INFO+convertSeverity Notice  = NOTICE+convertSeverity Warning = WARNING+convertSeverity Error   = ERROR
+ src/System/Wlog/Wrapper.hs view
@@ -0,0 +1,109 @@+-- |+-- Module      : System.Wlog.Wrapper+-- Copyright   : (c) Serokell, 2016+-- License     : GPL-3 (see the file LICENSE)+-- Maintainer  : Serokell <hi@serokell.io>+-- Stability   : experimental+-- Portability : POSIX, GHC+--+-- Logging functionality. This module is wrapper over+-- <http://hackage.haskell.org/package/hslogger hslogger>,+-- which allows to keep logger name in monadic context.++module System.Wlog.Wrapper+       ( LoggingFormat (..)+       , Severity (..)+       , convertSeverity+       , initLogging+       , initLoggingWith+       , releaseAllHandlers+       , setSeverity+       , setSeverityMaybe+       ) where++import           Control.Concurrent.MVar   (MVar, newMVar, withMVar)+import           Control.Monad.Trans       (MonadIO (liftIO))+import           Data.Default              (Default (def))+import           System.IO                 (Handle, stderr, stdout)+import           System.Log.Handler.Simple (GenericHandler (..), streamHandler)+import           System.Log.Logger         (Priority (DEBUG, ERROR), clearLevel,+                                            removeAllHandlers, rootLoggerName,+                                            setHandlers, setLevel, updateGlobalLogger)++import           System.Wlog.Formatter     (setStderrFormatter, setStdoutFormatter)+import           System.Wlog.LoggerName    (LoggerName (..))+import           System.Wlog.Severity      (Severity (..), convertSeverity)+++-- | Options determining formatting of messages.+data LoggingFormat = LoggingFormat+    { -- | Show time for non-error messages.+      -- Note that error messages always have timestamp.+      lfShowTime :: !Bool+    } deriving (Show)++instance Default LoggingFormat where+    def = LoggingFormat {lfShowTime = True}++-- | Like `streamHandler`, but syncronized using given `MVar` as lock+-- (it should be filled before this function call).+streamHandlerWithLock :: MVar () -> Handle -> Priority -> IO (GenericHandler Handle)+streamHandlerWithLock lock h p = do+    GenericHandler{..} <- streamHandler h p+    return GenericHandler+        { priority  = priority+        , formatter = formatter+        , privData  = privData+        , writeFunc = \a s -> withMVar lock $ const $ writeFunc a s+        , closeFunc = closeFunc+        }++-- | This function initializes global logging system. At high level, it sets+-- severity which will be used by all loggers by default, sets default+-- formatters and sets custom severity for given loggers (if any).+--+-- On a lower level it does the following:+-- 1. Removes default handler from root logger, sets two handlers such that:+-- 1.1. All messages are printed to /stdout/.+-- 1.2. Moreover messages with at least `Error` severity are+-- printed to /stderr/.+-- 2. Sets given Severity to root logger, so that it will be used by+-- descendant loggers by default.+-- 3. Applies `setSeverity` to given loggers. It can be done later using+-- `setSeverity` directly.+initLoggingWith+    :: MonadIO m+    => LoggingFormat -> Severity -> m ()+initLoggingWith LoggingFormat {..} defaultSeverity = liftIO $ do+    lock <- liftIO $ newMVar ()+    -- We set DEBUG here, to allow all messages by stdout handler.+    -- They will be filtered by loggers.+    stdoutHandler <- setStdoutFormatter lfShowTime <$>+        streamHandlerWithLock lock stdout DEBUG+    stderrHandler <- setStderrFormatter <$>+        streamHandlerWithLock lock stderr ERROR+    updateGlobalLogger rootLoggerName $+        setHandlers [stderrHandler, stdoutHandler]+    updateGlobalLogger rootLoggerName $+        setLevel (convertSeverity defaultSeverity)++-- | Version of initLoggingWith without any predefined loggers.+initLogging :: MonadIO m => Severity -> m ()+initLogging = initLoggingWith def++-- | Set severity for given logger. By default parent's severity is used.+setSeverity :: MonadIO m => LoggerName -> Severity -> m ()+setSeverity (LoggerName name) =+    liftIO . updateGlobalLogger name . setLevel . convertSeverity++-- | Set or clear severity.+setSeverityMaybe+    :: MonadIO m+    => LoggerName -> Maybe Severity -> m ()+setSeverityMaybe (LoggerName name) Nothing =+    liftIO $ updateGlobalLogger name clearLevel+setSeverityMaybe n (Just x) = setSeverity n x++-- | Lifted alias to 'removeAllHandlers'.+releaseAllHandlers :: MonadIO m => m ()+releaseAllHandlers = liftIO removeAllHandlers