1 files changed, 84 insertions, 0 deletions
diff --git a/src/Application.hs b/src/Application.hs
new file mode 100644
index 0000000..63aa258
--- /dev/null
+++ b/src/Application.hs
@@ -0,0 +1,84 @@
+{-# LANGUAGE DeriveGeneric #-}
+{-# LANGUAGE LambdaCase #-}
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE RecordWildCards #-}
+{-# LANGUAGE ScopedTypeVariables #-}
+
+module Application (
+  app
+) where
+
+import Prelude hiding (id)
+
+import Control.Monad.Trans (liftIO)
+import Data.Aeson (ToJSON)
+import Data.Default.Class (def)
+import Data.List (sort)
+import Data.Pool (Pool, withResource)
+import Data.Text.Lazy (Text)
+import Database.MySQL.Simple (Connection, query_)
+import GHC.Generics (Generic)
+import Network.HTTP.Types (notFound404)
+import Network.Wai (Application, Middleware)
+import Network.Wai.Middleware.RequestLogger (Destination(Handle),
+  mkRequestLogger, RequestLoggerSettings(destination, outputFormat),
+  OutputFormat(CustomOutputFormat))
+import Network.Wai.Middleware.Static (addBase, hasPrefix, staticPolicy, (>->))
+import System.IO (stderr)
+import Web.Scotty (ScottyM, ActionM, middleware, json, file, get,
+  status, text, param, scottyApp)
+import qualified Data.HashMap.Lazy as HM
+
+import LogFormat (logFormat)
+
+type Pools = HM.HashMap Text (Pool Connection)
+
+app :: Pools -> FilePath -> IO Application
+app ps f = do
+  logger <- mkRequestLogger def{ destination = Handle stderr
+                               , outputFormat = CustomOutputFormat logFormat }
+  scottyApp (myProcess ps logger f)
+
+myProcess :: Pools  -> Middleware -> FilePath -> ScottyM ()
+myProcess ps logger dataDir = do
+  let
+    index_html = dataDir ++ "/" ++ "index.html"
+
+  middleware logger
+
+  middleware $ staticPolicy (hasPrefix "static" >-> addBase dataDir)
+  get "/" $ file index_html
+  get "/index.html" $ file index_html
+
+  get "/serverlist.json" $ json (sort $ HM.keys ps)
+  get "/server/:server/processlist.json" $ apiGetProcesses ps
+
+data Process = Process {
+    id      :: Int
+  , user    :: Text
+  , host    :: Text
+  , db      :: Maybe Text
+  , command :: Text
+  , time    :: Int
+  , state   :: Text
+  , info    :: Text
+} deriving (Generic)
+instance ToJSON Process
+
+apiGetProcesses :: Pools -> ActionM ()
+apiGetProcesses ps = do
+  server <- param "server"
+  case HM.lookup server ps of
+    Nothing -> status notFound404 >> text server
+    Just p -> do
+      res <- withDB p $ \c ->
+              query_ c "SELECT \
+              \id, user, host, db, command, time, state, info \
+              \FROM information_schema.processlist \
+              \WHERE info IS NOT NULL \
+              \ORDER BY time DESC, id ASC"
+      json $ map (\(id, user, host, db, command, time, state, info) -> Process {..}) res
+
+withDB :: Pool Connection -> (Connection -> IO a) -> ActionM a
+withDB p a = liftIO $ withResource p (liftIO . a)
+