Safe Haskell	None
Language	Haskell2010

Log.Monad

Description

The LogT monad transformer for adding logging capabilities to any monad.

Synopsis

Documentation

data Logger Source #

An object used for communication with a logger thread that outputs LogMessages using e.g. PostgreSQL, Elasticsearch or stdout (depending on the back-end chosen).

Instances

Semigroup Logger Source #
Methods (<>) :: Logger -> Logger -> Logger # sconcat :: NonEmpty Logger -> Logger # stimes :: Integral b => b -> Logger -> Logger #
Monoid Logger Source #	Composition of `Logger` objects.
Methods mempty :: Logger # mappend :: Logger -> Logger -> Logger # mconcat :: [Logger] -> Logger #

data LoggerEnv Source #

The state that every LogT carries around.

Constructors

LoggerEnv
Fields leLogger :: !Logger The `Logger` to use. leComponent :: !Text Current application component. leDomain :: ![Text] Current application domain. leData :: ![Pair] Additional data to be merged with the log message's data.

type InnerLogT = ReaderT LoggerEnv Source #

newtype LogT m a Source #

Monad transformer that adds logging capabilities to the underlying monad.

Constructors

LogT
Fields unLogT :: InnerLogT m a

Instances

MonadTrans LogT Source #
Methods lift :: Monad m => m a -> LogT m a #
MonadTransControl LogT Source #
Associated Types type StT (LogT :: (* -> ) -> -> ) a :: # Methods liftWith :: Monad m => (Run LogT -> m a) -> LogT m a # restoreT :: Monad m => m (StT LogT a) -> LogT m a #
MonadBase b m => MonadBase b (LogT m) Source #
Methods liftBase :: b α -> LogT m α #
MonadBaseControl b m => MonadBaseControl b (LogT m) Source #
Associated Types type StM (LogT m :: * -> ) a :: # Methods liftBaseWith :: (RunInBase (LogT m) b -> b a) -> LogT m a # restoreM :: StM (LogT m) a -> LogT m a #
MonadError e m => MonadError e (LogT m) Source #
Methods throwError :: e -> LogT m a # catchError :: LogT m a -> (e -> LogT m a) -> LogT m a #
MonadReader r m => MonadReader r (LogT m) Source #
Methods ask :: LogT m r # local :: (r -> r) -> LogT m a -> LogT m a # reader :: (r -> a) -> LogT m a #
MonadState s m => MonadState s (LogT m) Source #
Methods get :: LogT m s # put :: s -> LogT m () # state :: (s -> (a, s)) -> LogT m a #
MonadWriter w m => MonadWriter w (LogT m) Source #
Methods writer :: (a, w) -> LogT m a # tell :: w -> LogT m () # listen :: LogT m a -> LogT m (a, w) # pass :: LogT m (a, w -> w) -> LogT m a #
Monad m => Monad (LogT m) Source #
Methods (>>=) :: LogT m a -> (a -> LogT m b) -> LogT m b # (>>) :: LogT m a -> LogT m b -> LogT m b # return :: a -> LogT m a # fail :: String -> LogT m a #
Functor m => Functor (LogT m) Source #
Methods fmap :: (a -> b) -> LogT m a -> LogT m b # (<$) :: a -> LogT m b -> LogT m a #
Applicative m => Applicative (LogT m) Source #
Methods pure :: a -> LogT m a # (<>) :: LogT m (a -> b) -> LogT m a -> LogT m b # (>) :: LogT m a -> LogT m b -> LogT m b # (<*) :: LogT m a -> LogT m b -> LogT m a #
Alternative m => Alternative (LogT m) Source #
Methods empty :: LogT m a # (<\|>) :: LogT m a -> LogT m a -> LogT m a # some :: LogT m a -> LogT m [a] # many :: LogT m a -> LogT m [a] #
MonadPlus m => MonadPlus (LogT m) Source #
Methods mzero :: LogT m a # mplus :: LogT m a -> LogT m a -> LogT m a #
MonadIO m => MonadIO (LogT m) Source #
Methods liftIO :: IO a -> LogT m a #
MonadThrow m => MonadThrow (LogT m) Source #
Methods throwM :: Exception e => e -> LogT m a #
MonadCatch m => MonadCatch (LogT m) Source #
Methods catch :: Exception e => LogT m a -> (e -> LogT m a) -> LogT m a #
MonadMask m => MonadMask (LogT m) Source #
Methods mask :: ((forall a. LogT m a -> LogT m a) -> LogT m b) -> LogT m b # uninterruptibleMask :: ((forall a. LogT m a -> LogT m a) -> LogT m b) -> LogT m b #
(MonadBase IO m, MonadTime m) => MonadLog (LogT m) Source #
Methods logMessage :: UTCTime -> LogLevel -> Text -> Value -> LogT m () Source # localData :: [Pair] -> LogT m a -> LogT m a Source # localDomain :: Text -> LogT m a -> LogT m a Source #
type StT LogT m Source #
type StT LogT m = StT InnerLogT m
type StM (LogT m) a Source #
type StM (LogT m) a = ComposeSt LogT m a

runLogT Source #

Arguments

:: Text	Application component name to use.
-> Logger	The logging back-end to use.
-> LogT m a	The `LogT` computation to run.
-> m a

Run a LogT computation.

Note that in the case of asynchronous/bulk loggers runLogT doesn't guarantee that all messages are actually written to the log once it finishes. Use withPGLogger or withElasticSearchLogger for that.

mapLogT :: (m a -> n b) -> LogT m a -> LogT n b Source #

Transform the computation inside a LogT.