System.Logger.Class

The MonadLogger type-class and associated functions.

Documentation

data Settings

type Renderer = ByteString -> DateFormat -> Level -> [Element] -> Builder

Take a custom separator, date format, log level of the event, and render a list of log fields or messages into a builder.

defSettings :: Settings

Default settings:

• logLevel = Debug
• output = StdOut
• format = iso8601UTC
• delimiter = ", "
• netstrings = False
• bufSize = defaultBufSize
• name = Nothing
• readEnvironment = True

logLevel :: Settings -> Level

setLogLevel :: Level -> Settings -> Settings

output :: Settings -> Output

setOutput :: Output -> Settings -> Settings

format :: Settings -> Maybe DateFormat

The time and date format used for the timestamp part of a log line.

setFormat :: Maybe DateFormat -> Settings -> Settings

delimiter :: Settings -> ByteString

Delimiter string which separates log line parts.

setDelimiter :: ByteString -> Settings -> Settings

setNetStrings :: Bool -> Settings -> Settings

Whether to use netstring encoding for log lines.

{-}

bufSize :: Settings -> Int

setBufSize :: Int -> Settings -> Settings

name :: Settings -> Maybe Text

setName :: Maybe Text -> Settings -> Settings

setRenderer :: Renderer -> Settings -> Settings

Set a custom renderer.

See setRendererDefault and setRendererNetstr for two common special cases.

renderer :: Settings -> Renderer

Output format

data Level

Constructors

Trace

Debug

Info

Warn

Error

Fatal

Instances

Eq Level

Defined in System.Logger.Settings

Methods

(==) :: Level -> Level -> Bool

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

Ord Level

Defined in System.Logger.Settings

Methods

compare :: Level -> Level -> Ordering

(<) :: Level -> Level -> Bool

(<=) :: Level -> Level -> Bool

(>) :: Level -> Level -> Bool

(>=) :: Level -> Level -> Bool

max :: Level -> Level -> Level

min :: Level -> Level -> Level

Read Level

Defined in System.Logger.Settings

Methods

readsPrec :: Int -> ReadS Level

readList :: ReadS [Level]

readPrec :: ReadPrec Level

readListPrec :: ReadPrec [Level]

Show Level

Defined in System.Logger.Settings

Methods

showsPrec :: Int -> Level -> ShowS

show :: Level -> String

showList :: [Level] -> ShowS

data Output

Constructors

StdOut

StdErr

Path FilePath

Instances

Eq Output

Defined in System.Logger.Settings

Methods

(==) :: Output -> Output -> Bool

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

Ord Output

Defined in System.Logger.Settings

Methods

compare :: Output -> Output -> Ordering

(<) :: Output -> Output -> Bool

(<=) :: Output -> Output -> Bool

(>) :: Output -> Output -> Bool

(>=) :: Output -> Output -> Bool

max :: Output -> Output -> Output

min :: Output -> Output -> Output

Show Output

Defined in System.Logger.Settings

Methods

showsPrec :: Int -> Output -> ShowS

show :: Output -> String

showList :: [Output] -> ShowS

data DateFormat

Instances

IsString DateFormat

Defined in System.Logger.Settings

Methods

fromString :: String -> DateFormat

iso8601UTC :: DateFormat

ISO 8601 date-time format.

data Logger

new :: MonadIO m => Settings -> m Logger

create :: MonadIO m => Output -> m Logger

Invokes new with default settings and the given output as log sink.

level :: Logger -> Level

Inspect this logger's threshold.

flush :: MonadIO m => Logger -> m ()

Force buffered bytes to output sink.

close :: MonadIO m => Logger -> m ()

Closes the logger.

clone :: Maybe Text -> Logger -> Logger

Clone the given logger and optionally give it a name (use Nothing to clear).

If logLevelOf returns a custom Level for this name then the cloned logger will use it for its log messages.

settings :: Logger -> Settings

class Monad m => MonadLogger m where

Methods

log :: Level -> (Msg -> Msg) -> m ()

trace :: MonadLogger m => (Msg -> Msg) -> m ()

Abbreviation for MonadLogger using the corresponding log level.

debug :: MonadLogger m => (Msg -> Msg) -> m ()

Abbreviation for MonadLogger using the corresponding log level.

info :: MonadLogger m => (Msg -> Msg) -> m ()

Abbreviation for MonadLogger using the corresponding log level.

warn :: MonadLogger m => (Msg -> Msg) -> m ()

Abbreviation for MonadLogger using the corresponding log level.

err :: MonadLogger m => (Msg -> Msg) -> m ()

Abbreviation for MonadLogger using the corresponding log level.

fatal :: MonadLogger m => (Msg -> Msg) -> m ()

Abbreviation for MonadLogger using the corresponding log level.

module System.Logger.Message