Log user ID

1 files changed, 40 insertions, 0 deletions

diff --git a/src/LogFormat.hs b/src/LogFormat.hs
new file mode 100644
index 0000000..51c36c6
--- /dev/null
+++ b/src/LogFormat.hs
@@ -0,0 +1,40 @@
+{-# LANGUAGE OverloadedStrings #-}
+
+module LogFormat (
+  logFormat
+) where
+
+import Data.Maybe (fromMaybe)
+import Data.Monoid ((<>))
+import Network.HTTP.Types (Status(statusCode))
+import Network.Wai (Request, httpVersion, requestHeaders, requestMethod,
+  rawPathInfo, requestHeaderReferer, requestHeaderUserAgent)
+import System.Log.FastLogger (LogStr, toLogStr)
+import qualified Data.ByteString.Char8 as BS
+
+-- Sligthly modified Common Log Format.
+-- User ID extracted from the From header.
+logFormat :: BS.ByteString -> Request -> Status -> Maybe Integer -> LogStr
+logFormat t req st msize = ""
+  <> toLogStr (fromMaybe "-" $ lookup "X-Forwarded-For" headers)
+  <> " - "
+  <> toLogStr (fromMaybe "-" $ lookup "From" headers)
+  <> " ["
+  <> toLogStr t
+  <> "] \""
+  <> toLogStr (requestMethod req)
+  <> " "
+  <> toLogStr (rawPathInfo req)
+  <> " "
+  <> toLogStr (show $ httpVersion req)
+  <> "\" "
+  <> toLogStr (show $ statusCode st)
+  <> " "
+  <> toLogStr (maybe "-" show msize)
+  <> " \""
+  <> toLogStr (fromMaybe "" $ requestHeaderReferer req)
+  <> "\" \""
+  <> toLogStr (fromMaybe "" $ requestHeaderUserAgent req)
+  <> "\"\n"
+  where headers = requestHeaders req
+