refactor: log server listening observations after listening socket is ready

Correct behavior is to log this after the listening socket is ready.

Signed-off-by: Taimoor Zaeem <taimoorzaeem@gmail.com>

src/PostgREST/Admin.hs

@@ -28,15 +28,14 @@ runAdmin appState maybeAdminSocket getSocketREST settings = do
   conf <- getConfig appState
   whenJust maybeAdminSocket $ \adminSocket -> do
     address <- resolveSocketToAddress adminSocket
-    observer $ AdminStartObs address
-    void . forkIO $ Warp.runSettingsSocket (adminServerSettings conf) adminSocket adminApp
+    void . forkIO $ Warp.runSettingsSocket (adminServerSettings conf address) adminSocket adminApp
   where
     adminApp = admin appState getSocketREST
     observer = AppState.getObserver appState
-    adminServerSettings config =
-      case configAdminServerPort config of
-        Just p  -> settings & Warp.setPort p
-        Nothing -> settings
+    adminServerSettings config addr=
+      settings
+        & Warp.setBeforeMainLoop (observer $ AdminStartObs addr)
+        & maybe identity Warp.setPort (configAdminServerPort config)
 
 -- | PostgREST admin application
 admin :: AppState.AppState -> IO (Maybe NS.Socket) -> Wai.Application

src/PostgREST/App.hs

@@ -29,8 +29,8 @@ import Data.Either.Combinators  (mapLeft, whenLeft)
 import Data.IORef               (atomicWriteIORef, newIORef,
                                  readIORef)
 import Data.String              (IsString (..), String)
-import Network.Wai.Handler.Warp (defaultSettings, setHost,
-                                 setOnException, setPort,
+import Network.Wai.Handler.Warp (defaultSettings, setBeforeMainLoop,
+                                 setHost, setOnException, setPort,
                                  setServerName)
 
 import qualified Data.Text.Encoding       as T
@@ -104,12 +104,12 @@ run appState = do
   let app = postgrest appState (AppState.schemaCacheLoader appState)
 
   address <- resolveSocketToAddress mainSocket
-  observer $ AppServerAddressObs address
 
   let
     appServerSettings = serverSettings conf
       & setPort (configServerPort conf)
       & setOnException onWarpException
+      & setBeforeMainLoop (observer $ AppServerAddressObs address)
 
   Warp.runSettingsSocket appServerSettings mainSocket app
   where