Safe Haskell	Safe-Inferred
Language	GHC2021

Control.Tracer.JSON

Contents

Tracer
Using it

Description

Structured JSON logging over the contra-tracer generic logging framework. A Tracer acquired here wraps each message in an Envelope carrying a timestamp, thread id and namespace, and writes it as one JSON object per line.

Synopsis

newtype Tracer (m :: Type -> Type) a = Tracer {
- runTracer :: a -> m ()
}
natTracer :: (forall x. m x -> n x) -> Tracer m s -> Tracer n s
nullTracer :: forall (m :: Type -> Type) a. Applicative m => Tracer m a
traceWith :: Tracer m a -> a -> m ()
contramap :: Contravariant f => (a' -> a) -> f a -> f a'
data Verbosity
- = Quiet
- | Verbose Text
data Envelope a = Envelope {
- timestamp :: UTCTime
- threadId :: Int
- namespace :: Text
- message :: a
}
defaultLogBuffering :: BufferMode
withTracer :: forall m msg a. (MonadIO m, MonadFork m, MonadTime m, ToJSON msg) => Verbosity -> (Tracer m msg -> IO a) -> IO a
withTracerOutputTo :: forall m msg a. (MonadIO m, MonadFork m, MonadTime m, ToJSON msg) => BufferMode -> Handle -> Text -> (Tracer m msg -> IO a) -> IO a
showLogsOnFailure :: (MonadLabelledSTM m, MonadCatch m, MonadFork m, MonadTime m, MonadSay m, ToJSON msg) => Text -> (Tracer m msg -> m a) -> m a
traceInTVar :: (MonadFork m, MonadTime m, MonadSTM m) => TVar m [Envelope msg] -> Text -> Tracer m msg
mkEnvelope :: (MonadFork m, MonadTime m) => Text -> msg -> m (Envelope msg)
defaultQueueSize :: Natural

Tracer

newtype Tracer (m :: Type -> Type) a #

Constructors

Tracer
Fields runTracer :: a -> m ()

Instances

Instances details

Contravariant (Tracer m)
Instance details Defined in Control.Tracer Methods contramap :: (a' -> a) -> Tracer m a -> Tracer m a' Source # (>$) :: b -> Tracer m b -> Tracer m a Source #
Applicative m => Monoid (Tracer m s)
Instance details Defined in Control.Tracer Methods mempty :: Tracer m s Source # mappend :: Tracer m s -> Tracer m s -> Tracer m s Source # mconcat :: [Tracer m s] -> Tracer m s Source #
Applicative m => Semigroup (Tracer m s)
Instance details Defined in Control.Tracer Methods (<>) :: Tracer m s -> Tracer m s -> Tracer m s Source # sconcat :: NonEmpty (Tracer m s) -> Tracer m s Source # stimes :: Integral b => b -> Tracer m s -> Tracer m s Source #

natTracer :: (forall x. m x -> n x) -> Tracer m s -> Tracer n s #

nullTracer :: forall (m :: Type -> Type) a. Applicative m => Tracer m a #

traceWith :: Tracer m a -> a -> m () #

contramap :: Contravariant f => (a' -> a) -> f a -> f a' Source #

Using it

data Verbosity Source #

Constructors

Quiet
Verbose Text

Instances

Instances details

FromJSON Verbosity Source #
Instance details Defined in Control.Tracer.JSON Methods parseJSON :: Value -> Parser Verbosity parseJSONList :: Value -> Parser [Verbosity] omittedField :: Maybe Verbosity
ToJSON Verbosity Source #
Instance details Defined in Control.Tracer.JSON Methods toJSON :: Verbosity -> Value toEncoding :: Verbosity -> Encoding toJSONList :: [Verbosity] -> Value toEncodingList :: [Verbosity] -> Encoding omitField :: Verbosity -> Bool
Generic Verbosity Source #
Instance details Defined in Control.Tracer.JSON Associated Types type Rep Verbosity :: Type -> Type Source # Methods from :: Verbosity -> Rep Verbosity x Source # to :: Rep Verbosity x -> Verbosity Source #
Show Verbosity Source #
Instance details Defined in Control.Tracer.JSON Methods showsPrec :: Int -> Verbosity -> ShowS Source # show :: Verbosity -> String Source # showList :: [Verbosity] -> ShowS Source #
Eq Verbosity Source #
Instance details Defined in Control.Tracer.JSON Methods (==) :: Verbosity -> Verbosity -> Bool Source # (/=) :: Verbosity -> Verbosity -> Bool Source #
type Rep Verbosity Source #
Instance details Defined in Control.Tracer.JSON type Rep Verbosity = D1 ('MetaData "Verbosity" "Control.Tracer.JSON" "contra-tracer-json-0.1.0.0-Ehq1kqfRLHnFfpOzXYyzFl" 'False) (C1 ('MetaCons "Quiet" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "Verbose" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 Text)))

data Envelope a Source #

Provides logging metadata for entries.

Constructors

Envelope
Fields timestamp :: UTCTime threadId :: Int namespace :: Text message :: a

Instances

Instances details

ToJSON a => ToJSON (Envelope a) Source #
Instance details Defined in Control.Tracer.JSON Methods toJSON :: Envelope a -> Value toEncoding :: Envelope a -> Encoding toJSONList :: [Envelope a] -> Value toEncodingList :: [Envelope a] -> Encoding omitField :: Envelope a -> Bool
Generic (Envelope a) Source #
Instance details Defined in Control.Tracer.JSON Associated Types type Rep (Envelope a) :: Type -> Type Source # Methods from :: Envelope a -> Rep (Envelope a) x Source # to :: Rep (Envelope a) x -> Envelope a Source #
Show a => Show (Envelope a) Source #
Instance details Defined in Control.Tracer.JSON Methods showsPrec :: Int -> Envelope a -> ShowS Source # show :: Envelope a -> String Source # showList :: [Envelope a] -> ShowS Source #
Eq a => Eq (Envelope a) Source #
Instance details Defined in Control.Tracer.JSON Methods (==) :: Envelope a -> Envelope a -> Bool Source # (/=) :: Envelope a -> Envelope a -> Bool Source #
type Rep (Envelope a) Source #
Instance details Defined in Control.Tracer.JSON type Rep (Envelope a) = D1 ('MetaData "Envelope" "Control.Tracer.JSON" "contra-tracer-json-0.1.0.0-Ehq1kqfRLHnFfpOzXYyzFl" 'False) (C1 ('MetaCons "Envelope" 'PrefixI 'True) ((S1 ('MetaSel ('Just "timestamp") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 UTCTime) :: S1 ('MetaSel ('Just "threadId") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 Int)) :: (S1 ('MetaSel ('Just "namespace") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 Text) :*: S1 ('MetaSel ('Just "message") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 a))))

defaultLogBuffering :: BufferMode Source #

Buffering used for log output. The writer batches whatever the queue holds and flushes each batch, so this bounds the syscalls rather than the latency.

withTracer :: forall m msg a. (MonadIO m, MonadFork m, MonadTime m, ToJSON msg) => Verbosity -> (Tracer m msg -> IO a) -> IO a Source #

Start logging thread and acquire a Tracer. This tracer will dump all messages on stdout, one message per line, formatted as JSON. This tracer is wrapping msg into an Envelope with metadata.

withTracerOutputTo :: forall m msg a. (MonadIO m, MonadFork m, MonadTime m, ToJSON msg) => BufferMode -> Handle -> Text -> (Tracer m msg -> IO a) -> IO a Source #

Start logging thread acquiring a Tracer, outputting JSON formatted messages to some Handle. This tracer is wrapping msg into an Envelope with metadata.

showLogsOnFailure :: (MonadLabelledSTM m, MonadCatch m, MonadFork m, MonadTime m, MonadSay m, ToJSON msg) => Text -> (Tracer m msg -> m a) -> m a Source #

Capture logs and output them to stdout when an exception was raised by the given action. This tracer is wrapping msg into an Envelope with metadata.

traceInTVar :: (MonadFork m, MonadTime m, MonadSTM m) => TVar m [Envelope msg] -> Text -> Tracer m msg Source #

mkEnvelope :: (MonadFork m, MonadTime m) => Text -> msg -> m (Envelope msg) Source #

defaultQueueSize :: Natural Source #