Install GHCJS for Stack

install-ghcjs-for-stack.hs

#!/usr/bin/env stack
-- stack --install-ghc runghc --package turtle --package wreq

{-# LANGUAGE OverloadedStrings #-}

import qualified Control.Foldl as Fold
import Control.Lens ((^.))
import Control.Monad (when)
import Data.ByteString.Lazy (hPut)
import Data.Maybe (fromMaybe)
import qualified Data.Text as T
import Data.Time.Format (formatTime, defaultTimeLocale)
import Network.Wreq (get, responseBody)
import Turtle


main = do
  dateStr <- T.pack . formatTime defaultTimeLocale "%Y%m%d" <$> date

  let url = "http://ghcjs.luite.com/master-"<>dateStr<>".tar.gz"
  echo $ format ("Downloading "%s%"...") url
  r <- get (T.unpack url)

  let tempdir = "temp-ghcjs-archive"
  echo $ format ("Using temp directory: "%fp) tempdir
  alreadyThere <- testdir tempdir
  when alreadyThere $ rmtree tempdir
  mkdir tempdir

  let tempfile = tempdir</>"archive.tar.gz"
  echo $ format ("Writing to "%fp%"...") tempfile
  with (writeonly tempfile) $ \temphandle->
    hPut temphandle (r ^. responseBody)

  echo "Unpacking..."
  proc "tar" ["-xzf", format fp tempfile, format ("-C"%fp) tempdir] empty
    .||. die "failed to unpack archive"

  Just ghcjsDir <- fold
    (ls tempdir)
    (Fold.find (T.isPrefixOf "ghcjs-" . format fp . filename))

  let newFolderName = ghcjsDir <.> dateStr
  let ghcjsStackVersion = format (fp%"_ghc-7.10.2") (filename newFolderName)
  let outputArchive = tempdir </> fromText ghcjsStackVersion <.> "tar.gz"

  mv ghcjsDir newFolderName
  echo $ format ("Archiving to "%fp) outputArchive

  targzPack (parent newFolderName) (filename newFolderName) outputArchive

  -- Install archive to the approprate stack folder
  Just outDir <- fold (inproc "stack" ["path", "--ghc-paths"] empty) Fold.head
  echo $ format ("Copying to "%s) outDir
  cp outputArchive (fromText outDir </> filename outputArchive)

  echo $ format ("DONE: Add 'compiler: "%s%"' or 'resolver: "%s%"' to your stack.yaml and run 'stack setup' to boot it.")
                ghcjsStackVersion ghcjsStackVersion

targzPack inDir inFile outFilePath =
    proc "tar" ["-czf", format fp outFilePath, format ("-C"%fp) inDir, format fp inFile] empty
      .||. die (format ("failed to create archive: "%fp) outFilePath)

Make this executable and run it. You need stack and tar on your PATH and I really hope you have installed wreq or the build time will be pretty horrid.

Once complete, it will tell you what to do.

great script thanks. to be a bit more explicit about the next step, maybe the script should echo
"Add 'compiler: "%s%"' to your stack.yaml... instead of
"Point to "%s%" in your stack.yaml...

Great idea, thanks. I edited it. I was originally ambiguous because you can also specify it in the resolver field (to not use a snapshot), but being explicit is much better.

It would be great it you could patch the .cabal to include the same version :)

Nice, thanks for writing this! So, the reason this script is necessary is that the folder within the sdist tarball needs to be renamed? Seems to me like we should just make stack agnostic of the particular "ghcjs-*" folder copied.

After successfully executing the script, either using the compiler or the resolver field leads to:

No information found for ghcjs-0.2.0.20151227_ghc-7.10.2.
Supported versions for OS key 'source': GhcjsVersion 0.1.0.20150924 7.10.2

Wow...apparently GitHub doesn't notify me when people comment on this. :/

@yamafaktory: Yes, apparently newer versions of stack don't play as nicely with this. I've found it still works but you must "fake" out stack by filling in the whole setup-info thing:

So for today's build, I would run the script and then add this to my .cabal file:

compiler: ghcjs-0.2.0.20160107_ghc-7.10.2
compiler-check: match-exact
setup-info:
  ghcjs:
      source:
            ghcjs-0.2.0.20160107_ghc-7.10.2:
                    url: "http://ghcjs.luite.com/master-20160107.tar.gz"

@mgsloan: I'd be much happier if stack didn't care about the folder name!

@mgsloan: @yamafaktory: Yay! This script will soon be obsolete! commercialhaskell/stack#1622

Note that this script is still handy if you want your ghcjs version to include the date.