Use yesod-gitrev and githash

config/routes

@@ -42,7 +42,7 @@
 /install InstallR GET
 /older-releases OlderReleasesR GET
 
-/build-version BuildVersionR GET
+/build-version BuildVersionR GitRev appGitRev
 
 /download DownloadR GET
 /download/snapshots.json DownloadSnapshotsJsonR GET

package.yaml

@@ -70,6 +70,7 @@ dependencies:
 - blaze-html
 - haddock-library
 - yesod-gitrepo
+- yesod-gitrev
 - hoogle
 - deepseq
 - auto-update

src/Application.hs

@@ -37,6 +37,7 @@ import           Stackage.Database (openStackageDatabase, PostgresConf (..))
 import           Stackage.Database.Cron (newHoogleLocker, singleRun)
 import           Control.AutoUpdate
 import           Control.Concurrent (threadDelay)
+import           Yesod.GitRev (tGitRev)
 
 -- Import all relevant handler modules here.
 -- Don't forget to add new modules to your cabal file!
@@ -51,7 +52,6 @@ import           Handler.Package
 import           Handler.PackageDeps
 import           Handler.PackageList
 import           Handler.Hoogle
-import           Handler.BuildVersion
 import           Handler.Sitemap
 import           Handler.BuildPlan
 import           Handler.Download
@@ -144,6 +144,7 @@ makeFoundation appSettings = do
     appMirrorStatus <- mkUpdateMirrorStatus
     hoogleLocker <- newHoogleLocker True appHttpManager
     let appGetHoogleDB = singleRun hoogleLocker
+    let appGitRev = $$tGitRev
 
     return App {..}
 

src/Foundation.hs

@@ -12,6 +12,7 @@ import           Yesod.AtomFeed
 import           Yesod.GitRepo
 import Stackage.Database
 import qualified Yesod.Core.Unsafe as Unsafe
+import           Yesod.GitRev (GitRev)
 
 -- | The site argument for your application. This can be a good place to
 -- keep settings and values requiring initialization before your application
@@ -31,6 +32,7 @@ data App = App
     -- https://github.com/fpco/stackage-server/issues/172
     , appMirrorStatus :: IO (Status, WidgetFor App ())
     , appGetHoogleDB :: SnapName -> IO (Maybe FilePath)
+    , appGitRev :: GitRev
     }
 
 instance HasHttpManager App where

src/Handler/BuildVersion.hs

@@ -1,29 +0,0 @@
-module Handler.BuildVersion where
-
-import Import hiding (lift)
-import Language.Haskell.TH.Syntax
-import System.Process (rawSystem)
-import System.Exit
-
-getBuildVersionR :: Handler Text
-getBuildVersionR = return $ pack $(do
-    let headFile = ".git/HEAD"
-    qAddDependentFile headFile
-    ehead <- qRunIO $ tryIO $ readFile $ headFile
-    case decodeUtf8 <$> ehead of
-        Left e -> lift $ ".git/HEAD not read: " ++ show e
-        Right raw ->
-            case takeWhile (/= '\n') <$> stripPrefix "ref: " raw of
-                Nothing -> lift $ ".git/HEAD not in expected format: " ++ show raw
-                Just fp' -> do
-                    let fp = ".git" </> unpack (fp' :: Text)
-                    qAddDependentFile fp
-                    bs <- qRunIO $ readFile fp
-                    isDirty <- qRunIO
-                             $ (/= ExitSuccess)
-                           <$> rawSystem "git" ["diff-files", "--quiet"]
-                    lift $ unpack $ unlines
-                        [ "Most recent commit: " ++ asText (decodeUtf8 bs)
-                        , "Working tree is " ++ (if isDirty then "dirty" else "clean")
-                        ]
-    )

stack.yaml

@@ -1,4 +1,5 @@
 resolver: nightly-2018-06-20
 extra-deps:
-- archive: https://github.com/snoyberg/gitrev/archive/6a1a639f493ac08959eb5ddf540ca1937baaaaf9.tar.gz
 - archive: https://github.com/bitemyapp/esqueleto/archive/b81e0d951e510ebffca03c5a58658ad884cc6fbd.tar.gz
+- archive: https://github.com/snoyberg/githash/archive/a80ff63bb32d2a3920bb870b4395ee231df0bd6e.tar.gz
+- archive: https://github.com/snoyberg/yesod-gitrev/archive/98383b2d5ddad23b1503468d83b2ced76e6c6fe8.tar.gz