Merge pull request #814 from omacom/slack-desktop-aarch64

Add slack-desktop for aarch64 on a native Electron runtime

pkgbuilds/slack-desktop/.omarchy/package.json

@@ -0,0 +1,9 @@
+{
+  "source": "local",
+  "upstream": {
+    "watch": {
+      "json": "https://slack.com/api/desktop.latestRelease?arch=x64&variant=deb",
+      "path": "version"
+    }
+  }
+}

pkgbuilds/slack-desktop/PKGBUILD

@@ -0,0 +1,160 @@
+# Maintainer: Ryan Hughes <ryan@omarchy.org>
+
+pkgname=slack-desktop
+pkgver=4.52.171
+pkgrel=1
+# Slack publishes Linux builds for x86_64 only. Its application code runs
+# unchanged on the AArch64 build of the Electron release it ships with; see
+# README.md for the native modules that are replaced or dropped.
+_electronver=44.4.5
+pkgdesc='Slack Desktop for Linux on a native AArch64 Electron runtime'
+arch=('aarch64')
+url='https://slack.com/downloads'
+license=('custom')
+depends=(
+  'alsa-lib'
+  'at-spi2-core'
+  'cairo'
+  'dbus'
+  'expat'
+  'fontconfig'
+  'gcc-libs'
+  'glib2'
+  'glibc'
+  'gtk3'
+  'libcups'
+  'libnotify'
+  'libsecret'
+  'libx11'
+  'libxcb'
+  'libxcomposite'
+  'libxdamage'
+  'libxext'
+  'libxfixes'
+  'libxkbcommon'
+  'libxrandr'
+  'mesa'
+  'nspr'
+  'nss'
+  'pango'
+  'systemd-libs'
+  'xdg-utils'
+)
+optdepends=(
+  'libappindicator-gtk3: Systray indicator support'
+  'org.freedesktop.secrets: Keyring password store support'
+)
+makedepends=('asar')
+options=('!debug' '!strip')
+source=(
+  "slack-desktop-${pkgver}-amd64.deb::https://downloads.slack-edge.com/desktop-releases/linux/x64/${pkgver}/slack-desktop-${pkgver}-amd64.deb"
+  "electron-v${_electronver}-linux-arm64.zip::https://github.com/electron/electron/releases/download/v${_electronver}/electron-v${_electronver}-linux-arm64.zip"
+  'slack.desktop'
+  'slack-desktop-utils.js'
+  'file-handler-info.js'
+  'electron-native-auth.js'
+)
+noextract=(
+  "slack-desktop-${pkgver}-amd64.deb"
+  "electron-v${_electronver}-linux-arm64.zip"
+)
+sha256sums=('c6199816e6d842289869a9e84a05042af6e0de68959df7a15e7273873b86dc36'
+            '3bf0acab49c4ea3c9283cdb86bf3dd7204bd52a6fba6c8ae51101bdba2adae0e'
+            'e438e78265f3e566990300946afb4ea5d09bcd8c426738ab8f486ae9ddb86c0f'
+            '6de40409af5a04605c3287cb3c661132eb55a4f636f7cd9bbfd456f4adf41971'
+            'a2a8fd45daa4f493ad4487da9f01477233feecfef360ed366bfb0a58f804890a'
+            '9cd53c84fdc407c83f2ca6e9485916296f3712b2742dcc0acf22fda5195ead50')
+
+# x86_64 addons in Slack's app that can never load on AArch64. The three that
+# Slack requires on Linux are replaced by the JavaScript files above; the rest
+# are Windows/macOS helpers or degrade on failure (native-keymap). Any other
+# foreign binary fails the build so a new native module gets reviewed.
+_x86_addons=(
+  '@tinyspeck/slack-desktop-utils/lib/binding/napi-v8/slackdesktoputils.node'
+  'file-handler-info/build/Release/file_handler_info.node'
+  'electron-native-auth/build/Release/electron_native_auth.node'
+  '@tinyspeck/native-keymap/build/Release/keymapping.node'
+  'cf-prefs/build/Release/cf-prefs.node'
+  'macos-notification-state/build/Release/notificationstate.node'
+  'registry-js/build/Release/registry.node'
+  'windows-focus-assist/build/Release/focusassist.node'
+)
+
+prepare() {
+  rm -rf slack electron app
+  mkdir slack electron
+  bsdtar -O -xf "slack-desktop-${pkgver}-amd64.deb" 'data.tar.*' | bsdtar -C slack -xf -
+  bsdtar -C electron -xf "electron-v${_electronver}-linux-arm64.zip"
+
+  local slack_electron
+  slack_electron=$(<slack/usr/lib/slack/version)
+  if [[ $slack_electron != "$_electronver" ]]; then
+    error "Slack $pkgver ships Electron $slack_electron, but _electronver is $_electronver."
+    plain "Set _electronver=$slack_electron and update its checksum."
+    return 1
+  fi
+
+  # Electron loads resources/app ahead of app.asar, so the extracted tree can
+  # carry the replacement modules without repacking the archive.
+  asar extract slack/usr/lib/slack/resources/app.asar app
+}
+
+package() {
+  local lib="$pkgdir/usr/lib/slack"
+  local app="$lib/resources/app"
+
+  install -d "$lib"
+  cp -a --no-preserve=ownership electron/. "$lib/"
+  mv "$lib/electron" "$lib/slack"
+  rm -f "$lib/resources/default_app.asar" "$lib/LICENSE"
+  find slack/usr/lib/slack/resources -maxdepth 1 -type f ! -name app.asar \
+    -exec cp --no-preserve=ownership -t "$lib/resources" {} +
+  cp -a --no-preserve=ownership app "$app"
+
+  local shim target
+  for shim in \
+    'slack-desktop-utils.js:@tinyspeck/slack-desktop-utils/lib/index.js' \
+    'file-handler-info.js:file-handler-info/index.js' \
+    'electron-native-auth.js:electron-native-auth/index.js'; do
+    target="$app/node_modules/${shim#*:}"
+    if [[ ! -f $target ]]; then
+      error "Slack $pkgver no longer ships ${shim#*:}; review the replacement modules."
+      return 1
+    fi
+    install -m644 "$srcdir/${shim%%:*}" "$target"
+  done
+
+  local addon
+  for addon in "${_x86_addons[@]}"; do
+    rm -f "$app/node_modules/$addon"
+  done
+
+  local file machine
+  while IFS= read -r -d '' file; do
+    machine=$(readelf -h "$file" 2>/dev/null |
+      sed -n 's/^[[:space:]]*Machine:[[:space:]]*//p')
+    case "$machine" in
+      '' | AArch64) ;;
+      *) error "Unexpected ${machine} binary: ${file#"$pkgdir"}"; return 1 ;;
+    esac
+  done < <(find "$lib" -type f -print0)
+
+  find "$lib" -type d -exec chmod 755 {} +
+  find "$lib" -type f -exec chmod 644 {} +
+  # Chromium sandboxes through unprivileged user namespaces, which Arch-family
+  # kernels allow; a setuid-root helper is not needed.
+  chmod 755 "$lib/slack" "$lib/chrome_crashpad_handler" "$lib/chrome-sandbox"
+
+  install -d "$pkgdir/usr/bin"
+  ln -s /usr/lib/slack/slack "$pkgdir/usr/bin/slack"
+  install -Dm644 slack.desktop "$pkgdir/usr/share/applications/slack.desktop"
+  install -Dm644 slack/usr/share/pixmaps/slack.png \
+    "$pkgdir/usr/share/icons/hicolor/512x512/apps/slack.png"
+
+  local licenses="$pkgdir/usr/share/licenses/$pkgname"
+  install -Dm644 slack/usr/lib/slack/LICENSE "$licenses/LICENSE"
+  install -Dm644 slack/usr/share/doc/slack-desktop/OPEN_SOURCE_LICENSE_ATTRIBUTIONS \
+    "$licenses/OPEN_SOURCE_LICENSE_ATTRIBUTIONS"
+  install -Dm644 electron/LICENSE "$licenses/LICENSE.electron.txt"
+  install -Dm644 electron/LICENSES.chromium.html "$licenses/LICENSES.chromium.html"
+}

pkgbuilds/slack-desktop/README.md

@@ -0,0 +1,22 @@
+# Slack on ARM
+
+Slack publishes Linux builds for x86_64 only, and the AUR `slack-desktop` recipe repackages that `.deb`. This package runs the same application code on the AArch64 build of the Electron release Slack ships with, so `yay -S slack-desktop` on an ARM Omarchy install resolves to a working package.
+
+## Electron version
+
+`_electronver` must equal the Electron version inside Slack's `.deb` (`usr/lib/slack/version`). `prepare()` refuses to build when they differ and prints the version to set. A Slack release that moves to a new Electron therefore fails its sync PR build until `_electronver` and the Electron checksum are updated; the upstream watch only tracks Slack's version.
+
+## Native modules
+
+Slack's app carries eight x86_64 Node addons. None can load on AArch64, so they are removed, and the build fails on any other foreign binary so a new native module is reviewed before it ships.
+
+Three are required while Slack boots on Linux and are replaced by JavaScript:
+
+- `file-handler-info` and `electron-native-auth` are MIT-licensed and their Linux builds compile no-op implementations (`impl_none.cc`, `addon_none.cc`). The replacements return the same results.
+- `@tinyspeck/slack-desktop-utils` is closed source. Its replacement throws `Method not implemented` from every native call, which is the error Slack's own wrapper uses for methods a platform lacks. Slack catches it, so these Linux features are unavailable: double-press and combo global shortcuts, the huddle screen-share border overlay, audio device detail lookups, clipboard set-and-paste, and haptics.
+
+`@tinyspeck/native-keymap` already catches a missing addon and returns defaults, so keyboard layout detection reports `unknown`. The other four addons are Windows/macOS helpers that Slack does not use on Linux.
+
+## Validation
+
+Installed and used on an aarch64 Omarchy machine (N1x). Features listed above as unavailable were not expected to work and were not checked.

pkgbuilds/slack-desktop/electron-native-auth.js

@@ -0,0 +1,14 @@
+// Linux builds of electron-native-auth (github.com/clavin/electron-native-auth)
+// compile src/addon_none.cc: native auth sessions are unavailable and
+// constructing a request throws. This is the same facade in JavaScript.
+class AuthRequest {
+  static isAvailable() {
+    return false;
+  }
+
+  constructor() {
+    throw new Error('this function is not implemented for this platform');
+  }
+}
+
+exports.AuthRequest = AuthRequest;

pkgbuilds/slack-desktop/file-handler-info.js

@@ -0,0 +1,9 @@
+// Linux builds of file-handler-info (github.com/clavin/node-file-handler-info)
+// compile src/impl_none.cc, which finds no handler. This is the same result
+// without an architecture-specific addon.
+exports.getHandlerInfo = (filePath) => {
+  if (typeof filePath !== 'string') {
+    throw new TypeError('Expected 1st argument to be string');
+  }
+  return { handlerPath: null, friendlyName: null };
+};

pkgbuilds/slack-desktop/slack-desktop-utils.js

@@ -0,0 +1,53 @@
+// Stand-in for Slack's closed-source native helpers, which ship no aarch64
+// build. Slack's main bundle requires this module while booting, so a missing
+// addon stops the window from ever opening. Every native call throws the same
+// error the vendor wrapper uses for methods a platform lacks, and Slack's call
+// sites already catch it and fall back.
+const unavailable = () => {
+  throw new Error('Method not implemented');
+};
+
+const namespace = new Proxy(
+  {},
+  {
+    get: (_, key) =>
+      typeof key === 'symbol' || key === 'then' ? undefined : unavailable,
+  },
+);
+
+const constants = {
+  AppRestartFlags: { NoCrash: 1, NoHang: 2, NoPatch: 4, NoReboot: 8 },
+  WindowsNotifierState: {
+    NotificationPlatformUnavailable: -2,
+    Error: -1,
+    Enabled: 0,
+    DisabledForApplication: 1,
+    DisabledForUser: 2,
+    DisabledByGroupPolicy: 3,
+    DisabledByManifest: 4,
+  },
+  StartupTaskState: {
+    Error: -1,
+    Disabled: 0,
+    DisabledByUser: 1,
+    Enabled: 2,
+    DisabledByPolicy: 3,
+    EnabledByPolicy: 4,
+  },
+  ActivationType: { Error: -1, StartupTask: 1020 },
+};
+
+module.exports = new Proxy(constants, {
+  get: (target, key) => {
+    if (key in target) return target[key];
+    if (
+      typeof key === 'symbol' ||
+      key === '__esModule' ||
+      key === 'default' ||
+      key === 'then'
+    ) {
+      return undefined;
+    }
+    return namespace;
+  },
+});

pkgbuilds/slack-desktop/slack.desktop

@@ -0,0 +1,11 @@
+[Desktop Entry]
+Name=Slack
+StartupWMClass=Slack
+Comment=Slack Desktop
+GenericName=Slack Client for Linux
+Exec=/usr/bin/slack %U
+Icon=slack
+Type=Application
+StartupNotify=true
+Categories=GNOME;GTK;Network;InstantMessaging;
+MimeType=x-scheme-handler/slack;