chore: move executable code to src/

src/ now contains all source code - in subdirectories, according to the
.cabal component they belong to. This will allow us to put vendored
libraries in the same place - and later split our own code into multiple
components/libraries as well.

src/library/PostgREST/Logger/Apache.hs

@@ -0,0 +1,48 @@
+module PostgREST.Logger.Apache
+  ( apacheFormat
+  ) where
+
+import qualified Data.ByteString.Char8 as BS
+import           Network.Wai.Logger
+import           System.Log.FastLogger
+
+import Network.HTTP.Types.Status (Status, statusCode)
+import Network.Wai
+
+import Protolude
+
+apacheFormat :: ToLogStr user => Maybe user -> FormattedTime -> Request -> Status -> Maybe Integer -> ByteString
+apacheFormat maybeUser tmstr req status msize =
+  fromLogStr $ apacheLogStr maybeUser tmstr req status msize
+
+-- This code is vendored from
+-- https://github.com/kazu-yamamoto/logger/blob/57bc4d3b26ca094fd0c3a8a8bb4421bcdcdd7061/wai-logger/Network/Wai/Logger/Apache.hs#L44-L45
+apacheLogStr :: ToLogStr user => Maybe user -> FormattedTime -> Request -> Status -> Maybe Integer -> LogStr
+apacheLogStr maybeUser tmstr req status msize =
+      toLogStr (getSourceFromSocket req)
+  <> " - "
+  <> maybe "-" toLogStr maybeUser
+  <> " ["
+  <> toLogStr tmstr
+  <> "] \""
+  <> toLogStr (requestMethod req)
+  <> " "
+  <> toLogStr path
+  <> " "
+  <> toLogStr (show (httpVersion req)::Text)
+  <> "\" "
+  <> toLogStr (show (statusCode status)::Text)
+  <> " "
+  <> toLogStr (maybe "-" show msize::Text)
+  <> " \""
+  <> toLogStr (fromMaybe "" mr)
+  <> "\" \""
+  <> toLogStr (fromMaybe "" mua)
+  <> "\"\n"
+  where
+    path = rawPathInfo req <> rawQueryString req
+    mr  = requestHeaderReferer req
+    mua = requestHeaderUserAgent req
+
+getSourceFromSocket :: Request -> ByteString
+getSourceFromSocket = BS.pack . showSockAddr . remoteHost