System.Log.Heavy.Types

This module contains generic types definition, along with some utilities.

Data types

type LogSource = [String]

Log message source. This is usually a list of program module names, for example ["System", "Log", "Heavy", "Types"].

data LogMessage

Log message structure. You usually will want to use some sort of shortcut function to create messages. There are some provided by this package:

• System.Log.Heavy.Shortcuts module exports simple functions, that can be used in simple cases, when you do not want to write or check message source.
• System.Log.Heavy.TH module exports TH macros, which correctly fill message source and location.

Constructors

forall vars.ClosedVarContainer vars => LogMessage

Fields

• lmLevel :: Level

  Log message level

• lmSource :: LogSource

  Log message source (module)

• lmLocation :: Loc

  Log message source (exact location). You usually will want to use TH quotes to fill this.

• lmFormatString :: Text

  Log message string format (in Data.Text.Format.Heavy syntax)

• lmFormatVars :: vars

  Log message substitution variables. Use () if you do not have variables.

• lmContext :: LogContext

  Logging context. Authomatically filled by logMessage.

type LogFilter = [(LogSource, Level)]

Log messages filter by source and level.

Semantics under this is that (source, severity) pair allows to write messages from source of severity (and all more important messages) to log.

data LogContextFrame

One frame in logging context stack.

Constructors

LogContextFrame

Fields

• lcfVariables :: [(Text, Variable)]

  Context variables

• lcfFilter :: LogContextFilter

  Context events filter

Instances

Show LogContextFrame

Defined in System.Log.Heavy.Types

Methods

showsPrec :: Int -> LogContextFrame -> ShowS

show :: LogContextFrame -> String

showList :: [LogContextFrame] -> ShowS

type LogContext = [LogContextFrame]

Logging context stack

class IsLogBackend b where

Logging backend class.

Minimal complete definition

makeLogger, initLogBackend, cleanupLogBackend

Associated Types

data LogBackendSettings b

Logging backend settings data type

Methods

makeLogger :: Logger b

Create logger from backend

initLogBackend :: LogBackendSettings b -> IO b

Initialize logging backend from settings

wouldWriteMessage :: b -> LogMessage -> IO Bool

Should return True if the specified message would be actually written to the log. Default implementation always returns True.

cleanupLogBackend :: b -> IO ()

Cleanup logging backend (release resources and so on)

withLoggingB :: (MonadBaseControl IO m, MonadIO m) => LogBackendSettings b -> (b -> m a) -> m a

Bracket function. Concrete implementations usually do not have to override default implementation.

Instances

IsLogBackend AnyLogBackend

Defined in System.Log.Heavy.Types

Associated Types

data LogBackendSettings AnyLogBackend

Methods

makeLogger :: Logger AnyLogBackend

initLogBackend :: LogBackendSettings AnyLogBackend -> IO AnyLogBackend

wouldWriteMessage :: AnyLogBackend -> LogMessage -> IO Bool

cleanupLogBackend :: AnyLogBackend -> IO ()

withLoggingB :: (MonadBaseControl IO m, MonadIO m) => LogBackendSettings AnyLogBackend -> (AnyLogBackend -> m a) -> m a

IsLogBackend DynamicBackend

Defined in System.Log.Heavy.Backends.Dynamic

Associated Types

data LogBackendSettings DynamicBackend

Methods

makeLogger :: Logger DynamicBackend

initLogBackend :: LogBackendSettings DynamicBackend -> IO DynamicBackend

wouldWriteMessage :: DynamicBackend -> LogMessage -> IO Bool

cleanupLogBackend :: DynamicBackend -> IO ()

withLoggingB :: (MonadBaseControl IO m, MonadIO m) => LogBackendSettings DynamicBackend -> (DynamicBackend -> m a) -> m a

IsLogBackend NullBackend

Defined in System.Log.Heavy.Backends

Associated Types

data LogBackendSettings NullBackend

Methods

makeLogger :: Logger NullBackend

initLogBackend :: LogBackendSettings NullBackend -> IO NullBackend

wouldWriteMessage :: NullBackend -> LogMessage -> IO Bool

cleanupLogBackend :: NullBackend -> IO ()

withLoggingB :: (MonadBaseControl IO m, MonadIO m) => LogBackendSettings NullBackend -> (NullBackend -> m a) -> m a

IsLogBackend ParallelBackend

Defined in System.Log.Heavy.Backends

Associated Types

data LogBackendSettings ParallelBackend

Methods

makeLogger :: Logger ParallelBackend

initLogBackend :: LogBackendSettings ParallelBackend -> IO ParallelBackend

wouldWriteMessage :: ParallelBackend -> LogMessage -> IO Bool

cleanupLogBackend :: ParallelBackend -> IO ()

withLoggingB :: (MonadBaseControl IO m, MonadIO m) => LogBackendSettings ParallelBackend -> (ParallelBackend -> m a) -> m a

IsLogBackend ChanLoggerBackend

Defined in System.Log.Heavy.Backends

Associated Types

data LogBackendSettings ChanLoggerBackend

Methods

makeLogger :: Logger ChanLoggerBackend

initLogBackend :: LogBackendSettings ChanLoggerBackend -> IO ChanLoggerBackend

wouldWriteMessage :: ChanLoggerBackend -> LogMessage -> IO Bool

cleanupLogBackend :: ChanLoggerBackend -> IO ()

withLoggingB :: (MonadBaseControl IO m, MonadIO m) => LogBackendSettings ChanLoggerBackend -> (ChanLoggerBackend -> m a) -> m a

IsLogBackend SyslogBackend

Defined in System.Log.Heavy.Backends

Associated Types

data LogBackendSettings SyslogBackend

Methods

makeLogger :: Logger SyslogBackend

initLogBackend :: LogBackendSettings SyslogBackend -> IO SyslogBackend

wouldWriteMessage :: SyslogBackend -> LogMessage -> IO Bool

cleanupLogBackend :: SyslogBackend -> IO ()

withLoggingB :: (MonadBaseControl IO m, MonadIO m) => LogBackendSettings SyslogBackend -> (SyslogBackend -> m a) -> m a

IsLogBackend FastLoggerBackend

Defined in System.Log.Heavy.Backends

Associated Types

data LogBackendSettings FastLoggerBackend

Methods

makeLogger :: Logger FastLoggerBackend

initLogBackend :: LogBackendSettings FastLoggerBackend -> IO FastLoggerBackend

wouldWriteMessage :: FastLoggerBackend -> LogMessage -> IO Bool

cleanupLogBackend :: FastLoggerBackend -> IO ()

withLoggingB :: (MonadBaseControl IO m, MonadIO m) => LogBackendSettings FastLoggerBackend -> (FastLoggerBackend -> m a) -> m a

IsLogBackend b => IsLogBackend (FilteringM b)

Defined in System.Log.Heavy.Backends.Dynamic

Associated Types

data LogBackendSettings (FilteringM b)

Methods

makeLogger :: Logger (FilteringM b)

initLogBackend :: LogBackendSettings (FilteringM b) -> IO (FilteringM b)

wouldWriteMessage :: FilteringM b -> LogMessage -> IO Bool

cleanupLogBackend :: FilteringM b -> IO ()

withLoggingB :: (MonadBaseControl IO m, MonadIO m) => LogBackendSettings (FilteringM b) -> (FilteringM b -> m a) -> m a

IsLogBackend b => IsLogBackend (Filtering b)

Defined in System.Log.Heavy.Backends

Associated Types

data LogBackendSettings (Filtering b)

Methods

makeLogger :: Logger (Filtering b)

initLogBackend :: LogBackendSettings (Filtering b) -> IO (Filtering b)

wouldWriteMessage :: Filtering b -> LogMessage -> IO Bool

cleanupLogBackend :: Filtering b -> IO ()

withLoggingB :: (MonadBaseControl IO m, MonadIO m) => LogBackendSettings (Filtering b) -> (Filtering b -> m a) -> m a

data LoggingSettings

A container for arbitrary logging backend. You usually will use this similar to:

 getLoggingSettings :: String -> LoggingSettings
 getLoggingSettings "syslog" = LoggingSettings defaultsyslogsettings

Constructors

forall b.IsLogBackend b => LoggingSettings (LogBackendSettings b)

data AnyLogBackend

Container data type for representing arbitrary logging backend.

Constructors

forall b.IsLogBackend b => AnyLogBackend b

Instances

IsLogBackend AnyLogBackend

Defined in System.Log.Heavy.Types

Associated Types

data LogBackendSettings AnyLogBackend

Methods

makeLogger :: Logger AnyLogBackend

initLogBackend :: LogBackendSettings AnyLogBackend -> IO AnyLogBackend

wouldWriteMessage :: AnyLogBackend -> LogMessage -> IO Bool

cleanupLogBackend :: AnyLogBackend -> IO ()

withLoggingB :: (MonadBaseControl IO m, MonadIO m) => LogBackendSettings AnyLogBackend -> (AnyLogBackend -> m a) -> m a

HasLogBackend AnyLogBackend IO

Defined in System.Log.Heavy.IO

Methods

getLogBackend :: IO AnyLogBackend

Monad m => HasLogBackend AnyLogBackend (LoggingT m)

Defined in System.Log.Heavy.LoggingT

Methods

getLogBackend :: LoggingT m AnyLogBackend

data LogBackendSettings AnyLogBackend

Defined in System.Log.Heavy.Types

data LogBackendSettings AnyLogBackend = AnyLogBackendSettings LoggingSettings

data LogContextFilter

Events filter for specific logging context.

Constructors

LogContextFilter

Fields

• setInclude :: Maybe LogFilter

  Positive filter (include specified messages)

• setExclude :: Maybe LogFilter

  Negative filter (exclude specified messages)

Instances

Eq LogContextFilter

Defined in System.Log.Heavy.Types

Methods

(==) :: LogContextFilter -> LogContextFilter -> Bool

(/=) :: LogContextFilter -> LogContextFilter -> Bool

Show LogContextFilter

Defined in System.Log.Heavy.Types

Methods

showsPrec :: Int -> LogContextFilter -> ShowS

show :: LogContextFilter -> String

showList :: [LogContextFilter] -> ShowS

include :: LogFilter -> LogContextFilter

Create filter which includes only specified messages

exclude :: LogFilter -> LogContextFilter

Create filter which just excludes specified messages

noChange :: LogContextFilter

Do not affect context filter settings

type Logger backend = backend -> LogMessage -> IO ()

Logging function

type SpecializedLogger = LogMessage -> IO ()

Logging function applied to concrete backend

class IsLogBackend b => HasLogBackend b m where

Constraint for monads in which it is possible to obtain logging backend.

Methods

getLogBackend :: m b

Instances

HasLogBackend AnyLogBackend IO

Defined in System.Log.Heavy.IO

Methods

getLogBackend :: IO AnyLogBackend

Monad m => HasLogBackend AnyLogBackend (LoggingT m)

Defined in System.Log.Heavy.LoggingT

Methods

getLogBackend :: LoggingT m AnyLogBackend

class Monad m => HasLogContext m where

Type class for monads that store logging context

Methods

withLogContext :: LogContextFrame -> m a -> m a

Execute actions within logging context frame

getLogContext :: m LogContext

Obtain currently active logging context stack

Instances

HasLogContext IO

Defined in System.Log.Heavy.IO

Methods

withLogContext :: LogContextFrame -> IO a -> IO a

getLogContext :: IO LogContext

Monad m => HasLogContext (LoggingT m)

Defined in System.Log.Heavy.LoggingT

Methods

withLogContext :: LogContextFrame -> LoggingT m a -> LoggingT m a

getLogContext :: LoggingT m LogContext

type HasLogging m = (HasLogger m, HasLogContext m)

Convinience constraint synonym.

class Monad m => HasLogger m where

Type class for monads that can write logs

Methods

getLogger :: m SpecializedLogger

localLogger :: SpecializedLogger -> m a -> m a

Change logger to specified one locally

Instances

HasLogger IO

Defined in System.Log.Heavy.IO

Methods

getLogger :: IO SpecializedLogger

localLogger :: SpecializedLogger -> IO a -> IO a

Monad m => HasLogger (LoggingT m)

Defined in System.Log.Heavy.LoggingT

Methods

getLogger :: LoggingT m SpecializedLogger

localLogger :: SpecializedLogger -> LoggingT m a -> LoggingT m a

Main functions

logMessage' :: forall m. (HasLogger m, MonadIO m) => LogMessage -> m ()

Log a message. This version is for monads that do not know about logging contexts.

applyBackend :: (IsLogBackend b, HasLogger m) => b -> m a -> m a

Apply logging backend locally.

defaultLogFilter :: LogFilter

Default log messages filter. This says pass all messages of level Info or higher.

withLogVariable

Arguments

:: (HasLogContext m, Formatable v)

=> Text

Variable name

-> v

Variable value

-> m a

Actions to execute within context frame

-> m a

Shortcut function to execute actions within logging context frame, which contains only one variable

Utility functions

splitString :: Char -> String -> [String]

Simple implementation of splitting string by character.

splitDots :: String -> [String]

Split string by dots

Orphan instances

(Monad m, MonadIO m, HasLogging m) => MonadLogger m

Compatibility instance.

Methods

monadLoggerLog :: ToLogStr msg => Loc -> LogSource -> LogLevel -> msg -> m ()

(Monad m, MonadIO m, HasLogging m) => MonadLoggerIO m

Another compatibility instance.

Methods

askLoggerIO :: m (Loc -> LogSource -> LogLevel -> LogStr -> IO ())

Formatable LogStr

Methods

formatVar :: VarFormat -> LogStr -> Either String Builder