Bring back menu items for logging in and out

src/Foundation.hs

@@ -36,13 +36,8 @@ data App = App
 data MenuItem = MenuItem
     { menuItemLabel :: Text
     , menuItemRoute :: Route App
-    , menuItemAccessCallback :: Bool
     }
 
-data MenuTypes
-    = NavbarLeft MenuItem
-    | NavbarRight MenuItem
-
 -- This is where we define all of the routes in our application. For a full
 -- explanation of the syntax, please see:
 -- http://www.yesodweb.com/book/routing-and-handlers
@@ -96,20 +91,14 @@ instance Yesod App where
         master <- getYesod
         mmsg <- getMessage
 
-        -- muser <- maybeAuthPair
+        muser <- maybeAuthPair
         mcurrentRoute <- getCurrentRoute
 
         -- Get the breadcrumbs, as defined in the YesodBreadcrumbs instance.
         (title, parents) <- breadcrumbs
 
-        -- Define the menu items of the header.
-        let menuItems = []
-
-        let navbarLeftMenuItems = [x | NavbarLeft x <- menuItems]
-        let navbarRightMenuItems = [x | NavbarRight x <- menuItems]
-
-        let navbarLeftFilteredMenuItems = [x | x <- navbarLeftMenuItems, menuItemAccessCallback x]
-        let navbarRightFilteredMenuItems = [x | x <- navbarRightMenuItems, menuItemAccessCallback x]
+        let navbarLeftMenuItems = leftMenuItems muser
+            navbarRightMenuItems = rightMenuItems muser
 
         -- We break up the default layout into two components:
         -- default-layout is the contents of the body tag, and
@@ -154,6 +143,17 @@ instance Yesod App where
 
     makeLogger = return . appLogger
 
+leftMenuItems, rightMenuItems :: Maybe (UserId, User) -> [MenuItem]
+leftMenuItems _ = []
+rightMenuItems = loggedOutItems `maybe` loggedInItems
+  where loggedOutItems =
+          [ "log in" `MenuItem` AuthR LoginR
+          ]
+        loggedInItems (_id, user) =
+          [ userUsername user `MenuItem` HomeR
+          , "log out" `MenuItem` AuthR LogoutR
+          ]
+
 -- Define breadcrumbs.
 instance YesodBreadcrumbs App where
   breadcrumb (AuthR _) = return ("login", Just HomeR)

templates/default-layout.hamlet

@@ -7,12 +7,12 @@
 
         <div #navbar .collapse.navbar-collapse>
             <ul .navbar-nav.mr-auto>
-                $forall MenuItem label route _ <- navbarLeftFilteredMenuItems
+                $forall MenuItem label route <- navbarLeftMenuItems
                     <li .nav-item :Just route == mcurrentRoute:.active>
                         <a .nav-link href=@{route}>#{label}
 
             <ul .navbar-nav>
-                $forall MenuItem label route _ <- navbarRightFilteredMenuItems
+                $forall MenuItem label route <- navbarRightMenuItems
                     <li .nav-item :Just route == mcurrentRoute:.active>
                         <a .nav-link href=@{route}>#{label}
     $if not $ null parents