Safe Haskell	None
Language	Haskell2010

System.Log.Heavy.Backends.Dynamic

Contents

Dynamic backend
Dynamic filtering

Description

This module incldues logging backend combinators that allow to change underlying backend or it's settings in runtime.

Synopsis

data DynamicBackend
data DynamicBackendHandle
newDynamicBackendHandle :: LoggingSettings -> IO DynamicBackendHandle
updateDynamicBackendSettings :: DynamicBackendHandle -> LoggingSettings -> IO ()
data family LogBackendSettings b
data FilteringM b
filteringM :: IsLogBackend b => LogFilter -> LogBackendSettings b -> IO (LogBackendSettings (FilteringM b))
excludingM :: IsLogBackend b => LogFilter -> LogBackendSettings b -> IO (LogBackendSettings (FilteringM b))

Dynamic backend

data DynamicBackend Source #

Dynamic logging backend allows to change logging backend or it's settings in runtime. When it sees new backend settings, it deinitializes old backend and initializes new one.

How to use it:

Before creating DynamicSettings, you have to select some initial LoggingSettings and create DynamicBackendHandle with it.
When you decide that you want to use new backend settings, call updateDynamicBackendSettings on existing DynamicBackendHandle. DynamicBackend will use new settings for the next logging function call.
It is responsibility of caller code to do not change backends too frequently; for example, if you are checking your config file for updates of logging settings each 10s, you have to check that settings actually changed since last time.

It is possible to create one instance of DynamicBackendHandle and pass it to multiple threads.

Instances

IsLogBackend DynamicBackend Source #
Instance details Defined in System.Log.Heavy.Backends.Dynamic Associated Types data LogBackendSettings DynamicBackend :: Type Source # Methods makeLogger :: Logger DynamicBackend Source # initLogBackend :: LogBackendSettings DynamicBackend -> IO DynamicBackend Source # wouldWriteMessage :: DynamicBackend -> LogMessage -> IO Bool Source # cleanupLogBackend :: DynamicBackend -> IO () Source # withLoggingB :: (MonadBaseControl IO m, MonadIO m) => LogBackendSettings DynamicBackend -> (DynamicBackend -> m a) -> m a Source #
data LogBackendSettings DynamicBackend Source #
Instance details Defined in System.Log.Heavy.Backends.Dynamic data LogBackendSettings DynamicBackend = DynamicSettings DynamicBackendHandle

data DynamicBackendHandle Source #

Abstract handle, that is used to control DynamicBackend.

newDynamicBackendHandle Source #

Arguments

:: LoggingSettings	Initial logging settings. This can be changed later with `updateDynamicBackendSettings`.
-> IO DynamicBackendHandle

Create an instance of DynamicBackendHandle.

updateDynamicBackendSettings Source #

Arguments

:: DynamicBackendHandle	Handle of `DynamicBackend`.
-> LoggingSettings	New logging settings.
-> IO ()

Update settings of DynamicBackend, which was created by provided handle.

data family LogBackendSettings b Source #

Logging backend settings data type

Instances

data LogBackendSettings AnyLogBackend Source #
Instance details Defined in System.Log.Heavy.Types data LogBackendSettings AnyLogBackend = AnyLogBackendSettings LoggingSettings
data LogBackendSettings DynamicBackend Source #
Instance details Defined in System.Log.Heavy.Backends.Dynamic data LogBackendSettings DynamicBackend = DynamicSettings DynamicBackendHandle
data LogBackendSettings NullBackend Source #
Instance details Defined in System.Log.Heavy.Backends data LogBackendSettings NullBackend = NullLogSettings
data LogBackendSettings ParallelBackend Source #
Instance details Defined in System.Log.Heavy.Backends data LogBackendSettings ParallelBackend = ParallelLogSettings [LoggingSettings]
data LogBackendSettings ChanLoggerBackend Source #
Instance details Defined in System.Log.Heavy.Backends data LogBackendSettings ChanLoggerBackend = ChanLoggerSettings (Chan LogMessage)
data LogBackendSettings SyslogBackend Source #
Instance details Defined in System.Log.Heavy.Backends data LogBackendSettings SyslogBackend = SyslogSettings { ssFormat :: Format ssIdent :: String ssOptions :: [Option] ssFacility :: Facility }
data LogBackendSettings FastLoggerBackend Source #
Instance details Defined in System.Log.Heavy.Backends data LogBackendSettings FastLoggerBackend = FastLoggerSettings { lsFormat :: Format lsType :: LogType }
data LogBackendSettings (FilteringM b) Source #
Instance details Defined in System.Log.Heavy.Backends.Dynamic data LogBackendSettings (FilteringM b) = FilteringM (MVar (LogMessage -> Bool)) (LogBackendSettings b)
data LogBackendSettings (Filtering b) Source #
Instance details Defined in System.Log.Heavy.Backends data LogBackendSettings (Filtering b) = Filtering (LogMessage -> Bool) (LogBackendSettings b)

Dynamic filtering

data FilteringM b Source #

Filtering backend with mutable filter.

Instances

IsLogBackend b => IsLogBackend (FilteringM b) Source #
Instance details Defined in System.Log.Heavy.Backends.Dynamic Associated Types data LogBackendSettings (FilteringM b) :: Type Source # Methods makeLogger :: Logger (FilteringM b) Source # initLogBackend :: LogBackendSettings (FilteringM b) -> IO (FilteringM b) Source # wouldWriteMessage :: FilteringM b -> LogMessage -> IO Bool Source # cleanupLogBackend :: FilteringM b -> IO () Source # withLoggingB :: (MonadBaseControl IO m, MonadIO m) => LogBackendSettings (FilteringM b) -> (FilteringM b -> m a) -> m a Source #
data LogBackendSettings (FilteringM b) Source #
Instance details Defined in System.Log.Heavy.Backends.Dynamic data LogBackendSettings (FilteringM b) = FilteringM (MVar (LogMessage -> Bool)) (LogBackendSettings b)

filteringM :: IsLogBackend b => LogFilter -> LogBackendSettings b -> IO (LogBackendSettings (FilteringM b)) Source #

Specify filter as LogFilter. This filter can be changed later.

excludingM :: IsLogBackend b => LogFilter -> LogBackendSettings b -> IO (LogBackendSettings (FilteringM b)) Source #

Exclude messages by filter. This filter can be changed later.