feat: add primer-miso, a re-implementation of Primer's UI in Haskell

WIP.

Signed-off-by: Drew Hess <[email protected]>

Makefile

@@ -15,6 +15,7 @@ package-targets = update-tests
 $(package-targets):
 	$(MAKE) -C primer $@
 	$(MAKE) -C primer-api $@
+	$(MAKE) -C primer-miso $@
 	$(MAKE) -C primer-selda $@
 	$(MAKE) -C primer-service $@
 	$(MAKE) -C primer-benchmark $@

Makefile.wasm32

@@ -22,7 +22,17 @@ $(test-targets):
 update:
 	$(CABAL) update
 
+frontend:
+	$(MAKE) -C primer-miso frontend
+
+frontend-prod:
+	$(MAKE) -C primer-miso frontend-prod
+
+serve-frontend:
+	$(MAKE) -C primer-miso serve-frontend
+
 clean:
 	$(CABAL) clean
+	$(MAKE) -C primer-miso clean
 
 .PHONY: build configure $(test-targets) update clean

cabal.project

@@ -6,10 +6,12 @@ if arch(wasm32)
   packages:
     primer
     primer-api
+    primer-miso
 else
   packages:
     primer
     primer-api
+    primer-miso
     primer-selda
     primer-service
     primer-benchmark
@@ -69,6 +71,14 @@ source-repository-package
   subdir: selda selda-sqlite
   --sha256: 0fw336sb03sc54pzmkz6jn989zvbnwnzypb9n0ackprymnvh8mym
 
+-- Until a new Hackage release is made which includes
+-- https://github.com/dmjio/miso/pull/752
+source-repository-package
+  type: git
+  location: https://github.com/dmjio/miso
+  tag: 2b548d48bffb0e8ae28a6cfb886e4afb0d8be37a
+  --sha256: sha256-fzDEa8vKXgxPPB+8NDLmhn2Jw1UDZso7e/klwidCfhM=
+
 -- Wasm workarounds.
 --
 -- We would prefer that these workarounds were not Wasm-dependent;

flake.nix

@@ -333,11 +333,11 @@
             wasm = pkgs.mkShell {
               packages = with inputs.ghc-wasm.packages.${system};
                 [
-                  wasm32-wasi-ghc-9_10
-                  wasm32-wasi-cabal-9_10
-                  wasmtime
+                  all_9_10
 
                   pkgs.gnumake
+                  pkgs.simple-http-server
+                  pkgs.brotli
 
                   # We need to run native `tasty-discover` at compile
                   # time, because we can't do it via `wasmtime`.

primer-miso/.gitignore

@@ -0,0 +1,2 @@
+dist/
+ghc_wasm_jsffi.js

primer-miso/Makefile

@@ -0,0 +1,5 @@
+# NOTE:
+#
+# This Makefile assumes you're using the `nix develop` shell.
+
+include ../makefiles/common.mk

primer-miso/Makefile.wasm32

@@ -0,0 +1,26 @@
+# NOTE:
+#
+# This Makefile assumes you're using the `nix develop .#wasm` shell.
+
+CABAL = wasm32-wasi-cabal
+
+build:	configure
+	$(CABAL) build
+
+frontend: build
+	./build-frontend.sh
+
+frontend-prod: build
+	./build-frontend.sh -Oz
+
+serve-frontend: frontend
+	simple-http-server -i -p 8000 -- dist
+
+configure:
+	$(CABAL) configure
+
+clean:
+	$(CABAL) clean
+	rm -rf dist/
+
+.PHONY: build configure clean

primer-miso/build-frontend.sh

@@ -0,0 +1,39 @@
+#!/usr/bin/env bash
+
+set -e
+
+if [ $# -eq 0 ]; then
+    echo "Building for dev"
+    dev_mode=true
+else
+    echo "Building for prod"
+    dev_mode=false
+fi
+
+rm -rf dist
+mkdir dist
+cp frontend/*.html dist/
+
+hs_wasm_path=$(wasm32-wasi-cabal list-bin -v0 exe:primer-miso)
+
+ghc_wasm_jsffi="dist/ghc_wasm_jsffi.js"
+
+"$(wasm32-wasi-ghc --print-libdir)"/post-link.mjs \
+                                   --input "$hs_wasm_path" --output "$ghc_wasm_jsffi"
+
+if ! [ -f "$ghc_wasm_jsffi" ] ; then
+    echo "post-link.mjs didn't produce a $ghc_wasm_jsffi file. Make sure you're in the Nix Wasm shell."
+    exit 1
+fi
+
+if $dev_mode; then
+    cp "$hs_wasm_path" dist/bin.wasm
+else
+    wizer --allow-wasi --wasm-bulk-memory true --init-func _initialize -o dist/bin.wasm "$hs_wasm_path"
+    wasm-opt ${1+"$@"} dist/bin.wasm -o dist/bin.wasm
+    wasm-tools strip -o dist/bin.wasm dist/bin.wasm
+    brotli --rm --best dist/bin.wasm -o dist/bin.wasm.br
+    mv dist/bin.wasm.br dist/bin.wasm
+fi
+
+cp frontend/*.js dist

primer-miso/exe/Main.hs

@@ -0,0 +1,32 @@
+{-# LANGUAGE CPP #-}
+
+#ifdef wasi_HOST_OS
+
+module MyMain (main) where
+
+import Foreword
+
+--import GHC.Wasm.Prim
+import Language.Javascript.JSaddle.Wasm qualified as JSaddle.Wasm
+import Primer.Miso (start)
+
+foreign export javascript "hs_start" main :: IO ()
+
+main :: IO ()
+main = JSaddle.Wasm.run start
+
+#else
+
+module Main (main) where
+
+import Foreword
+
+import Language.Javascript.JSaddle.Warp
+import Primer.Miso (start)
+
+-- Note that `debug` works with `cabal repl` but not `cabal run`.
+-- The best workflow is to run `ghcid -c "cabal repl primer-miso" -W -T ':main'`.
+main :: IO ()
+main = debug 8000 start
+
+#endif

primer-miso/frontend/index.html

@@ -0,0 +1,14 @@
+<!DOCTYPE html>
+<html>
+
+<head>
+        <meta charset="utf-8">
+        <meta name="viewport" content="width=device-width, initial-scale=1">
+        <title>Primer</title>
+</head>
+
+<body>
+        <script src="index.js" type="module"></script>
+</body>
+
+</html>

primer-miso/frontend/index.js

@@ -0,0 +1,22 @@
+import { WASI, OpenFile, File, ConsoleStdout } from "https://cdn.jsdelivr.net/npm/@bjorn3/[email protected]/dist/index.js";
+import ghc_wasm_jsffi from "./ghc_wasm_jsffi.js";
+
+const args = [];
+const env = [];
+const fds = [
+  new OpenFile(new File([])), // stdin
+  ConsoleStdout.lineBuffered((msg) => console.log(`[WASI stdout] ${msg}`)),
+  ConsoleStdout.lineBuffered((msg) => console.warn(`[WASI stderr] ${msg}`)),
+];
+const options = { debug: false };
+const wasi = new WASI(args, env, fds, options);
+
+const instance_exports = {};
+const { instance } = await WebAssembly.instantiateStreaming(fetch("bin.wasm"), {
+  wasi_snapshot_preview1: wasi.wasiImport,
+  ghc_wasm_jsffi: ghc_wasm_jsffi(instance_exports),
+});
+Object.assign(instance_exports, instance.exports);
+
+wasi.initialize(instance);
+await instance.exports.hs_start();

primer-miso/primer-miso.cabal

@@ -0,0 +1,107 @@
+cabal-version: 3.0
+name:          primer-miso
+version:       0.8.0.0
+license:       AGPL-3.0-or-later
+license-file:  COPYING
+copyright:     (c) 2024 Hackworth Ltd
+maintainer:    [email protected]
+author:        Hackworth Ltd <[email protected]>
+stability:     experimental
+synopsis:
+  A web frontend for building Primer programs, using the Miso framework
+
+category:      UI
+
+library
+  exposed-modules:
+    Primer.Miso
+    Primer.Miso.Colors
+    Primer.Miso.Layout
+    Primer.Miso.Util
+
+  hs-source-dirs:     src
+  default-language:   GHC2021
+  default-extensions:
+    DataKinds
+    DeriveAnyClass
+    DerivingStrategies
+    DerivingVia
+    LambdaCase
+    NoImplicitPrelude
+    OverloadedStrings
+
+  ghc-options:
+    -Wall -Wincomplete-uni-patterns -Wincomplete-record-updates
+    -Wcompat -Widentities -Wredundant-constraints
+    -Wmissing-deriving-strategies -fhide-source-paths
+
+  build-depends:
+    , aeson           >=2.0      && <2.3
+    , base            >=4.12     && <4.21
+    , bytestring      >=0.10.8.2 && <0.13
+    , containers      >=0.6.0.1  && <0.7.0
+    , data-default    ^>=0.8.0.0
+    , deriving-aeson  >=0.2      && <0.3.0
+    , extra           >=1.7.10   && <1.8.0
+    , jsaddle         ^>=0.9.9.2
+    , linear          ^>=1.23
+    , miso            ^>=1.8.5.0
+    , mtl             >=2.2.2    && <2.4.0
+    , optics          >=0.4      && <0.5.0
+    , primer          ^>=0.7.2
+    , text            >=2.0      && <2.2
+    , uniplate        >=1.6      && <1.7.0
+
+  if arch(wasm32)
+    build-depends: jsaddle-wasm ^>=0.0.1.0
+
+  else
+    build-depends:
+      , jsaddle-warp  ^>=0.9.9.2
+      , warp          >=3.3       && <3.5
+      , websockets    ^>=0.13.0.0
+
+executable primer-miso
+  main-is:            Main.hs
+  hs-source-dirs:     exe
+  default-language:   GHC2021
+  default-extensions:
+    DataKinds
+    DeriveAnyClass
+    DerivingStrategies
+    DerivingVia
+    LambdaCase
+    NoImplicitPrelude
+    OverloadedStrings
+
+  ghc-options:
+    -Wall -Wincomplete-uni-patterns -Wincomplete-record-updates
+    -Wcompat -Widentities -Wredundant-constraints
+    -Wmissing-deriving-strategies -fhide-source-paths
+
+  build-depends:
+    , base
+    , jsaddle
+    , primer
+    , primer-miso
+
+  if arch(wasm32)
+    build-depends:
+      , ghc-experimental  ^>=0.1.0.0
+      , jsaddle-wasm
+
+    ghc-options:
+      -no-hs-main -optl-mexec-model=reactor "-optl-Wl,--export=hs_start"
+
+  else
+    build-depends:
+      , jsaddle-warp
+      , warp
+      , websockets
+
+    ghc-options:   -threaded -rtsopts -with-rtsopts=-N
+
+  extra-source-files:
+    build-frontend.sh
+    frontend/**/*.html
+    frontend/**/*.js