952c02f · elk · git.iko.soy

git.iko.soy/elk

Improve error messages when elm input file or binary can't be found

There are a few problems currently with the elm server: 1. When the elm binary is not found, a nondescript error is displayed 2. When a file has a suffix .elm but the file is not found, the same error as in (1) is displayed 3. When a non-existing file ending in .elm is requested, the error code is incorrect - the elm-server returns a 400 instead of a 404 The following is the error message that shows up in cases (1) and (2) above: Server error: elm-server-cache: getDirectoryContents: does not exist (No such file or directory) This commit fixes the generic runtime errors (source of (1) and (2) above) by guarding against trying to delete a non-existing directory. It also fixes the HTTP code for non-existing .elm files by returning the general Happstack 404 page that is returned for other not-found requests.

commit952c02fabf498eda404dcf8e7a235e4e744d02a8 authorJustin Leitgeb <justin@stackbuilders.com> dateFri 11 Oct 2013, 14:51 (13 years ago) parent05dbca5

1 file changed+16−6

compare with master

unifiedsplit

server/Server.hs+16−6

server/Server.hs+16−6

@@ -1,7 +1,7 @@

22module Main where

4−import Control.Monad (msum,guard)

4+import Control.Monad (msum,guard,when)

55import Control.Monad.Trans (MonadIO(liftIO))

66import Data.List (isPrefixOf, isSuffixOf, (\\))

77import Data.Version (showVersion)

@@ -34,17 +34,23 @@ serve portNumber libLoc = do

3434pageTitle :: String -> String

3535pageTitle = dropExtension . takeBaseName

3636

37+defaultCacheDirectory = "elm-server-cache"

38+

3739serveElm :: FilePath -> ServerPartT IO Response

3840serveElm fp = do

39− guard (takeExtension fp == ".elm")

40− let file = tail fp

41− args = [ "--make" ,"--runtime=" ++ runtime,

42− "--cache-dir=elm-server-cache", file ]

41+ fileExists <- liftIO $ doesFileExist file

42+ guard $ fileExists && takeExtension fp == ".elm"

43+

4344 (_, stdout, _, handle) <- liftIO $ createProcess $

4445 (proc "elm" args) { std_out = CreatePipe }

4546 exitCode <- liftIO $ waitForProcess handle

46− liftIO $ removeDirectoryRecursive "elm-server-cache"

47+

48+ dirExists <- liftIO $ doesDirectoryExist defaultCacheDirectory

49+ when dirExists $ liftIO $ removeDirectoryRecursive defaultCacheDirectory

50+

4751 case (exitCode, stdout) of

52+ (ExitFailure 127, _) ->

53+ badRequest $ toResponse "Error: elm binary not found in your path."

4854 (ExitFailure _, Just out) ->

4955 do str <- liftIO $ hGetContents out

5056 badRequest $ toResponse str

@@ -54,6 +60,10 @@ serveElm fp = do

5460 serveFile

5561 (asContentType "text/html") ("build" </> replaceExtension file "html")

5662

63+ where file = tail fp

64+ args = [ "--make" ,"--runtime=" ++ runtime,

65+ "--cache-dir=" ++ defaultCacheDirectory, file ]

66+

5767serveLib :: FilePath -> [Char] -> ServerPartT IO Response

5868serveLib libLoc fp = do

5969 guard (fp == runtime)