Safe Haskell	None
Language	Haskell2010

Network.Wai.Logger

Contents

High level functions
Creating a logger
Types
Utilities
Backward compability

Description

Apache style logger for WAI applications.

An example:

{-# LANGUAGE OverloadedStrings #-}
module Main where

import Data.ByteString.Builder (byteString)
import Control.Monad.IO.Class (liftIO)
import qualified Data.ByteString.Char8 as BS
import Network.HTTP.Types (status200)
import Network.Wai (Application, responseBuilder)
import Network.Wai.Handler.Warp (run)
import Network.Wai.Logger (withStdoutLogger, ApacheLogger)

main :: IO ()
main = withStdoutLogger $ \aplogger ->
    run 3000 $ logApp aplogger

logApp :: ApacheLogger -> Application
logApp aplogger req response = do
    liftIO $ aplogger req status (Just len)
    response $ responseBuilder status hdr msg
  where
    status = status200
    hdr = [("Content-Type", "text/plain")]
    pong = "PONG"
    msg = byteString pong
    len = fromIntegral $ BS.length pong

Synopsis

type ApacheLogger = Request -> Status -> Maybe Integer -> IO ()
withStdoutLogger :: (ApacheLogger -> IO a) -> IO a
type ServerPushLogger = Request -> ByteString -> Integer -> IO ()
data ApacheLoggerActions
apacheLogger :: ApacheLoggerActions -> ApacheLogger
serverpushLogger :: ApacheLoggerActions -> ServerPushLogger
logRotator :: ApacheLoggerActions -> IO ()
logRemover :: ApacheLoggerActions -> IO ()
initLogger :: IPAddrSource -> LogType -> IO FormattedTime -> IO ApacheLoggerActions
data IPAddrSource
- = FromSocket
- | FromHeader
- | FromFallback
data LogType
- = LogNone
- | LogStdout BufSize
- | LogStderr BufSize
- | LogFileNoRotate FilePath BufSize
- | LogFile FileLogSpec BufSize
- | LogCallback (LogStr -> IO ()) (IO ())
data FileLogSpec = FileLogSpec {
- log_file :: FilePath
- log_file_size :: Integer
- log_backup_number :: Int
}
showSockAddr :: SockAddr -> NumericAddress
logCheck :: LogType -> IO ()
clockDateCacher :: IO (DateCacheGetter, DateCacheUpdater)
type ZonedDate = FormattedTime
type DateCacheGetter = IO ZonedDate
type DateCacheUpdater = IO ()

High level functions

type ApacheLogger = Request -> Status -> Maybe Integer -> IO () Source #

Apache style logger.

withStdoutLogger :: (ApacheLogger -> IO a) -> IO a Source #

Executing a function which takes ApacheLogger. This ApacheLogger writes log message to stdout. Each buffer (4K bytes) is flushed every second.

type ServerPushLogger = Request -> ByteString -> Integer -> IO () Source #

HTTP/2 server push logger in Apache style.

Creating a logger

data ApacheLoggerActions Source #

Function set of Apache style logger.

apacheLogger :: ApacheLoggerActions -> ApacheLogger Source #

The Apache logger.

serverpushLogger :: ApacheLoggerActions -> ServerPushLogger Source #

The HTTP/2 server push logger.

logRotator :: ApacheLoggerActions -> IO () Source #

This is obsoleted. Rotation is done on-demand. So, this is now an empty action.

logRemover :: ApacheLoggerActions -> IO () Source #

Removing resources relating to Apache logger. E.g. flushing and deallocating internal buffers.

initLogger :: IPAddrSource -> LogType -> IO FormattedTime -> IO ApacheLoggerActions Source #

Creating ApacheLogger according to LogType.

Types

data IPAddrSource Source #

Source from which the IP source address of the client is obtained.

Constructors

FromSocket	From the peer address of the HTTP connection.
FromHeader	From X-Real-IP: or X-Forwarded-For: in the HTTP header.
FromFallback	From the peer address if header is not found.

data LogType #

Logger Type.

Constructors

LogNone	No logging.
LogStdout BufSize	Logging to stdout. `BufSize` is a buffer size for each capability.
LogStderr BufSize	Logging to stderr. `BufSize` is a buffer size for each capability.
LogFileNoRotate FilePath BufSize	Logging to a file. `BufSize` is a buffer size for each capability.
LogFile FileLogSpec BufSize	Logging to a file. `BufSize` is a buffer size for each capability. File rotation is done on-demand.
LogCallback (LogStr -> IO ()) (IO ())	Logging with a log and flush action. run flush after log each message.

data FileLogSpec #

The spec for logging files

Constructors

FileLogSpec
Fields log_file :: FilePath log_file_size :: Integer Max log file size (in bytes) before requiring rotation. log_backup_number :: Int Max number of rotated log files to keep around before overwriting the oldest one.

Utilities

showSockAddr :: SockAddr -> NumericAddress Source #

Convert SockAddr to NumericAddress. If the address is IPv4-embedded IPv6 address, the IPv4 is extracted.

logCheck :: LogType -> IO () Source #

Backward compability

clockDateCacher :: IO (DateCacheGetter, DateCacheUpdater) Source #

Returning DateCacheGetter and DateCacheUpdater.

Note: Since version 2.1.2, this function uses the auto-update package internally, and therefore the DateCacheUpdater value returned need not be called. To wit, the return value is in fact an empty action.

type ZonedDate = FormattedTime Source #

A type for zoned date.

type DateCacheGetter = IO ZonedDate Source #

Getting cached ZonedDate.

type DateCacheUpdater = IO () Source #

Updateing cached ZonedDate. This should be called every second. See the source code of withStdoutLogger.