release.hs: constant for GPG options

Author: borsboom

doc/MAINTAINER_GUIDE.md

@@ -2,6 +2,10 @@
 
 ## Next release:
 
+* Check that GPG signature for
+  [Releases](https://s3.amazonaws.com/download.fpcomplete.com/debian/dists/jessie/Release)
+  uses SHA512, and close
+  [#1943](https://github.com/commercialhaskell/stack/issues/1934)
 * Integrate FreeBSD binaries and packages
   [#1253](https://github.com/commercialhaskell/stack/issues/1253#issuecomment-185993240)
 

etc/scripts/release.hs

@@ -221,7 +221,7 @@ rules global@Global{..} args = do
     releaseDir </> binaryPkgSignatureFileName %> \out -> do
         need [out -<.> ""]
         _ <- liftIO $ tryJust (guard . isDoesNotExistError) (removeFile out)
-        cmd "gpg --detach-sig --digest-algo=sha512 --armor"
+        cmd ("gpg " ++ gpgOptions ++ " --detach-sig --armor")
             [ "-u", gGpgKey
             , dropExtension out ]
 
@@ -250,15 +250,15 @@ rules global@Global{..} args = do
            need [pkgFile]
            () <- cmd "deb-s3 upload --preserve-versions --bucket download.fpcomplete.com"
                [ "--sign=" ++ gGpgKey
-               , "--gpg-options=--digest-algo=sha512"
+               , "--gpg-options=" ++ gpgOptions
                , "--prefix=" ++ dvDistro
                , "--codename=" ++ dvCodeName
                , pkgFile ]
            -- Also upload to the old, incorrect location for people who still have their systems
            -- configured with it.
            () <- cmd "deb-s3 upload --preserve-versions --bucket download.fpcomplete.com"
                [ "--sign=" ++ gGpgKey
-               , "--gpg-options=--digest-algo=sha512"
+               , "--gpg-options=" ++ gpgOptions
                , "--prefix=" ++ dvDistro ++ "/" ++ dvCodeName
                , pkgFile ]
            copyFileChanged pkgFile out
@@ -603,6 +603,10 @@ stackArgs Global{..} = ["--install-ghc", "--arch=" ++ display gArch]
 stackProgName :: FilePath
 stackProgName = "stack"
 
+-- | Options to pass to invocations of gpg
+gpgOptions :: String
+gpgOptions = "--digest-algo=sha512"
+
 -- | Linux distribution/version combination.
 data DistroVersion = DistroVersion
     { dvDistro :: !String