yet-another-logger-0.1: Yet Another Logger

CopyrightCopyright (c) 2014-2015 PivotCloud, Inc.
LicenseApache License, Version 2.0
MaintainerLars Kuhtz <lkuhtz@pivotmail.com>
Stabilityexperimental
Safe HaskellNone
LanguageHaskell2010

System.Logger.Logger.Internal

Contents

Description

This module provides a logger that implements the logger interface that is defined in System.Logger.Types.

If you want to roll your own implementation you may use the code in this module as an example and starting point.

Synopsis

Logger Configuration

data LoggerConfig Source

Logger Configuration

Constructors

LoggerConfig 

Fields

_loggerConfigQueueSize :: !Int
 
_loggerConfigThreshold :: !LogLevel

initial log threshold, can be changed later on

_loggerConfigScope :: !LogScope

initial stack of log labels, can be extended later on

_loggerConfigPolicy :: !LogPolicy

how to deal with a congested logging pipeline

Instances

loggerConfigQueueSize :: Lens' LoggerConfig Int Source

loggerConfigThreshold :: Lens' LoggerConfig LogLevel Source

loggerConfigScope :: Lens' LoggerConfig LogScope Source

defaultLoggerConfig :: LoggerConfig Source

validateLoggerConfig :: ConfigValidation LoggerConfig λ Source

pLoggerConfig :: MParser LoggerConfig Source

Logger

data Logger a Source

Instances

Generic (Logger a) 
LoggerCtx (Logger a) a 
Typeable (* -> *) Logger 
type Rep (Logger a) 

loggerScope :: Lens' (Logger a) LogScope Source

loggerThreshold :: Lens' (Logger a) LogLevel Source

createLogger :: MonadIO μ => LoggerConfig -> LoggerBackend a -> μ (Logger a) Source

releaseLogger :: MonadIO μ => Logger a -> μ () Source

withLogger :: (MonadIO μ, MonadBaseControl IO μ) => LoggerConfig -> LoggerBackend a -> (Logger a -> μ α) -> μ α Source

Provide a computation with a Logger.

Here is an example how this can be used to run a computation with a MonadLog constraint:

withConsoleLogger
    ∷ (MonadIO m, MonadBaseControl IO m)
    ⇒ LogLevel
    → LoggerT T.Text m α
    → m α
withConsoleLogger level inner = do
   withHandleBackend (config ^. logConfigBackend) $ \backend →
       withLogger (config ^. logConfigLogger) backend $ runLoggerT inner
 where
   config = defaultLogConfig
       & logConfigLogger ∘ loggerConfigThreshold .~ level

loggCtx :: (Show a, Typeable a, NFData a) => Logger a -> LogFunctionIO a Source

withLogFunction :: (Show a, Typeable a, NFData a, MonadIO μ, MonadBaseControl IO μ) => LoggerConfig -> LoggerBackend a -> (LogFunctionIO a -> μ α) -> μ α Source

For simple cases, when the logger threshold and the logger scope is constant this function can be used to directly initialize a log function.

LoggerT Monad Transformer

type LoggerT a = LoggerCtxT (Logger a) Source

runLoggerT :: LoggerT a m α -> Logger a -> m α Source

runLogT :: (MonadBaseControl IO m, MonadIO m) => LoggerConfig -> LoggerBackend msg -> LoggerT msg m α -> m α Source

Convenience function that unwraps a MonadLog computation over a newly created Logger