Implement Linux WebKitGTK host

.github/workflows/ci.yml

@@ -49,3 +49,39 @@ jobs:
       - run: mix test
         env:
           DESKTOP_WEBVIEW_BINARY: ${{ github.workspace }}/priv/native/macos/DesktopWebView
+
+  linux-e2e:
+    name: Linux host + E2E
+    runs-on: ubuntu-latest
+    env:
+      NO_WX: "1"
+    steps:
+      - uses: actions/checkout@v4
+      - uses: erlef/setup-beam@v1
+        with:
+          otp-version: "26"
+          elixir-version: "1.18"
+      - name: Checkout desktop (path dep)
+        uses: actions/checkout@v4
+        with:
+          repository: elixir-desktop/desktop
+          path: desktop
+      - name: Install GTK / WebKitGTK
+        run: |
+          sudo apt-get update -qq
+          sudo apt-get install -y \
+            build-essential cmake pkg-config \
+            libgtk-4-dev libwebkitgtk-6.0-dev \
+            libnotify-dev libjson-glib-dev \
+            xvfb dbus-x11
+      - name: Build host
+        run: ./scripts/build_linux.sh
+      - run: mix deps.get
+      - name: E2E under Xvfb
+        run: dbus-run-session -- xvfb-run -a mix test
+        env:
+          DESKTOP_WEBVIEW_BINARY: ${{ github.workspace }}/priv/native/linux/DesktopWebView
+          WEBKIT_DISABLE_COMPOSITING_MODE: "1"
+          WEBKIT_DISABLE_DMABUF_RENDERER: "1"
+          WEBKIT_DISABLE_SANDBOX_THIS_IS_DANGEROUS: "1"
+          LIBGL_ALWAYS_SOFTWARE: "1"

.github/workflows/release.yml

@@ -34,5 +34,32 @@ jobs:
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
 
+  linux:
+    name: Linux x86_64 artifact
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - name: Install GTK / WebKitGTK
+        run: |
+          sudo apt-get update -qq
+          sudo apt-get install -y \
+            build-essential cmake pkg-config \
+            libgtk-4-dev libwebkitgtk-6.0-dev \
+            libnotify-dev libjson-glib-dev
+      - name: Build host
+        run: ./scripts/build_linux.sh
+      - name: Pack
+        run: |
+          mkdir -p dist
+          cp priv/native/linux/DesktopWebView dist/DesktopWebView-linux-x86_64
+          sha256sum dist/DesktopWebView-linux-x86_64 > dist/DesktopWebView-linux-x86_64.sha256
+      - uses: softprops/action-gh-release@v2
+        with:
+          draft: true
+          files: |
+            dist/DesktopWebView-linux-x86_64
+            dist/DesktopWebView-linux-x86_64.sha256
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+
   # windows: add when native/windows host exists — attach DesktopWebView-windows-* to the same draft release
-  # linux:   add when native/linux host exists — attach DesktopWebView-linux-* to the same draft release

.gitignore

@@ -12,6 +12,8 @@ desktop_webview-*.tar
 *.xcworkspace/xcuserdata/
 native/macos/.build/
 native/macos/Package.resolved
+native/linux/build/
 priv/native/macos/DesktopWebView
+priv/native/linux/DesktopWebView
 .DS_Store
 *.swp

README.md

@@ -12,7 +12,7 @@ spawns the BEAM release; in development an existing BEAM can launch the host wit
 |----------|--------|--------|
 | macOS | WKWebView | Primary — see [docs/status/macos.md](docs/status/macos.md) |
 | Windows | WebView2 | Planned — [docs/status/windows.md](docs/status/windows.md) |
-| Linux | WebKitGTK | Planned — [docs/status/linux.md](docs/status/linux.md) |
+| Linux | WebKitGTK | Usable — [docs/status/linux.md](docs/status/linux.md) |
 
 ## Quick start (development)
 
@@ -25,10 +25,11 @@ config :desktop, :backend, DesktopWebview.Backend
 config :desktop, :menu_adapter, DesktopWebview.Menu.Adapter
 ```
 
-Build the macOS host (or use the vendored binary under `priv/native/macos/`):
+Build the native host for your OS (or use a vendored/CI binary):
 
 ```bash
-./scripts/build_macos.sh
+./scripts/build_macos.sh   # macOS → priv/native/macos/DesktopWebView
+./scripts/build_linux.sh   # Linux → priv/native/linux/DesktopWebView
 mix test          # unit
 mix test.e2e      # needs host binary; starts with --edw-test-rpc
 ```

docs/packaging.md

@@ -71,7 +71,10 @@ MyApp/
 - Release asset name: `DesktopWebView-linux-x86_64`.
 - Prefer shipping against a documented WebKitGTK/GTK baseline (note distro
   packages in `native/linux/README.md`).
-- Tray: StatusNotifierItem when available.
+  Ubuntu 24.04 baseline: GTK 4.14 + WebKitGTK 2.52 (`libgtk-4-dev`,
+  `libwebkitgtk-6.0-dev`).
+- Tray: StatusNotifierItem when available; current host keeps an in-memory tray
+  for RPC conformance (AppIndicator is GTK 3 and not linked).
 - Microphone / camera: PipeWire/Pulse + portal prompts may appear; hybrid
   permission policy still applies. Flatpak/snap portals need extra packaging
   notes when those formats are supported.

docs/status/linux.md

@@ -2,35 +2,36 @@
 
 States: `done` | `partial` | `todo` | `n/a`
 
-Host not implemented yet. Follow [docs/porting.md](../porting.md).
-Binary delivery via GitHub Releases (not Hex `priv/`).
+Host: GTK 4 + WebKitGTK 6 (`native/linux/`). Binary delivery via GitHub Releases
+(not Hex `priv/`); local/CI uses `./scripts/build_linux.sh` →
+`priv/native/linux/DesktopWebView` or `DESKTOP_WEBVIEW_BINARY`.
 
 | Feature | Status | Notes |
 |---------|--------|-------|
-| TCP listen + `listening <port>` | todo | |
-| `initialize` + capabilities | todo | |
-| `--edw-no-beam` / argv strip | todo | |
-| Ini + defaults | todo | |
-| Lifetime reconnect | todo | |
-| Lifetime coupled | todo | |
-| Window open/show/hide/title/min size | todo | |
-| Multi-window (ids) | todo | |
-| Close veto → Elixir | todo | |
-| Raise / iconize / shown / active | todo | |
-| Webview loadURL / reload / current URL | todo | |
-| Webview rebuild | todo | |
-| New window → external open | todo | |
-| Context menu disable | todo | |
-| Menubar from DOM | todo | |
-| Tray / status item | todo | |
-| Apple menu | n/a | |
-| Notifications | todo | |
-| Icons from path / PNG | todo | |
-| OS events (reopen, open url/file) | todo | |
-| Locale / os_description | todo | |
-| Permission policy hybrid | todo | |
-| Microphone in webview | todo | |
-| Camera in webview | todo | |
-| Test RPC channel | todo | |
+| TCP listen + `listening <port>` | done | |
+| `initialize` + capabilities | done | `platform: "linux"` |
+| `--edw-no-beam` / argv strip | done | |
+| Ini + defaults | done | beside executable |
+| Lifetime reconnect | done | default |
+| Lifetime coupled | done | |
+| Window open/show/hide/title/min size | done | |
+| Multi-window (ids) | done | |
+| Close veto → Elixir | done | |
+| Raise / iconize / shown / active | done | |
+| Webview loadURL / reload / current URL | done | |
+| Webview rebuild | done | |
+| New window → external open | done | |
+| Context menu disable | done | |
+| Menubar from DOM | done | GtkPopoverMenuBar + GMenu |
+| Tray / status item | done | In-memory tray for RPC; visual SNI/AppIndicator still TBD |
+| Apple menu | n/a | successful no-op |
+| Notifications | done | libnotify (falls back to stderr log) |
+| Icons from path / PNG | done | |
+| OS events (reopen, open url/file) | partial | `system.open_url` works; desktop-file reopen/open-file TBD |
+| Locale / os_description | done | |
+| Permission policy hybrid | done | |
+| Microphone in webview | done | E2E via test RPC + fixture |
+| Camera in webview | done | E2E via test RPC + fixture |
+| Test RPC channel | done | `--edw-test-rpc` |
 | Release artifact download | todo | |
-| CI build | todo | |
+| CI build | done | ubuntu-latest + xvfb |

lib/desktop_webview/launcher.ex

@@ -40,7 +40,10 @@ defmodule DesktopWebview.Launcher do
 
       case await_listening(port, Keyword.get(opts, :timeout, 10_000)) do
         {:ok, listen_port} ->
-          {:ok, %{port: port, listen_port: listen_port, binary: binary}}
+          # Keep draining host stdout/stderr so WebKit logs cannot fill the pipe.
+          drain_pid = spawn_link(fn -> drain_port(port) end)
+          true = Port.connect(port, drain_pid)
+          {:ok, %{port: port, listen_port: listen_port, binary: binary, drain_pid: drain_pid}}
 
         {:error, reason} ->
           Port.close(port)
@@ -49,7 +52,12 @@ defmodule DesktopWebview.Launcher do
     end
   end
 
-  def stop(%{port: port}) when is_port(port) do
+  def stop(%{port: port} = launcher) when is_port(port) do
+    if pid = Map.get(launcher, :drain_pid) do
+      Process.unlink(pid)
+      Process.exit(pid, :kill)
+    end
+
     try do
       case Port.info(port) do
         nil -> :ok
@@ -101,4 +109,11 @@ defmodule DesktopWebview.Launcher do
       end
     end
   end
+
+  defp drain_port(port) do
+    receive do
+      {^port, {:data, _}} -> drain_port(port)
+      {^port, {:exit_status, _}} -> :ok
+    end
+  end
 end

mise.toml

@@ -0,0 +1,3 @@
+[tools]
+erlang = "26"
+elixir = "1.18.4-otp-26"

native/linux/CMakeLists.txt

@@ -0,0 +1,28 @@
+cmake_minimum_required(VERSION 3.16)
+project(DesktopWebView LANGUAGES CXX)
+
+set(CMAKE_CXX_STANDARD 17)
+set(CMAKE_CXX_STANDARD_REQUIRED ON)
+set(CMAKE_CXX_EXTENSIONS OFF)
+
+find_package(PkgConfig REQUIRED)
+pkg_check_modules(DEPS REQUIRED IMPORTED_TARGET
+  gtk4
+  webkitgtk-6.0
+  libnotify
+  json-glib-1.0
+)
+
+add_executable(DesktopWebView
+  src/main.cpp
+  src/config.cpp
+  src/json_util.cpp
+  src/rpc_server.cpp
+  src/web_window.cpp
+  src/host_controller.cpp
+)
+
+target_include_directories(DesktopWebView PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/src)
+target_link_libraries(DesktopWebView PRIVATE PkgConfig::DEPS)
+
+install(TARGETS DesktopWebView RUNTIME DESTINATION bin)

native/linux/README.md

@@ -1,19 +1,63 @@
 # Linux host (WebKitGTK)
 
-Not implemented yet. This directory will hold the WebKitGTK host.
+C++ + **GTK 4** + **WebKitGTK 6** executable `DesktopWebView`.
 
-## Specs
+## Distro packages (Ubuntu 24.04 / noble)
+
+Build:
+
+```text
+build-essential cmake pkg-config
+libgtk-4-dev
+libwebkitgtk-6.0-dev
+libnotify-dev
+libjson-glib-dev
+```
+
+Runtime (same SONAMEs): `libgtk-4-1`, `libwebkitgtk-6.0-4`, `libnotify4`,
+`libjson-glib-1.0-0`.
+
+Baseline verified in CI: GTK **4.14**, WebKitGTK **2.52** (`webkitgtk-6.0`).
+
+Tray: AppIndicator libraries are GTK 3 and are not linked into this GTK 4 process.
+`tray.*` RPC succeeds with an in-memory tray; StatusNotifierItem integration is
+tracked as partial in [status/linux.md](../../docs/status/linux.md).
+
+## Build
+
+```bash
+# from repo root
+./scripts/build_linux.sh
 
-- [Porting guide](../../docs/porting.md) — checklist, toolchain, E2E gate
-- [Protocol](../../docs/protocol.md) — JSON-RPC + behavioral semantics
-- [Packaging](../../docs/packaging.md) — Linux layout and release artifact names
-- [Status](../../docs/status/linux.md) — feature matrix
+# or
+cmake -S native/linux -B native/linux/build -DCMAKE_BUILD_TYPE=Release
+cmake --build native/linux/build
+```
 
-## Contract (summary)
+Output is copied to `priv/native/linux/DesktopWebView` for local/CI use.
+Release artifact name: `DesktopWebView-linux-x86_64` (see [packaging.md](../../docs/packaging.md)).
+
+## Run (dev / E2E)
+
+```bash
+./priv/native/linux/DesktopWebView --edw-no-beam --edw-test-rpc --edw-port=0
+# prints: listening <port>
+```
+
+Headless CI needs a display (`xvfb-run` or a pre-set `DISPLAY`).
+
+## Structure
+
+| Path | Role |
+|------|------|
+| `CMakeLists.txt` | CMake project |
+| `src/` | Host sources (config, RPC, windows, dispatch) |
+
+Do not add a native unit-test suite; exercise the binary from Elixir E2E (`mix test.e2e`).
+
+## Specs
 
-- Native process listens on TCP; Elixir connects
-- JSON-RPC 2.0 over 4-byte length-prefixed frames
-- `--edw-*` host flags; remaining argv forwarded to BEAM
-- Binary: `DesktopWebView-linux-x86_64` via GitHub Releases (not Hex `priv/`)
-- `menu.set_apple` → successful no-op
-- Document GTK / WebKitGTK package versions here when the host lands
+- [Porting guide](../../docs/porting.md)
+- [Protocol](../../docs/protocol.md)
+- [Packaging](../../docs/packaging.md)
+- [Status](../../docs/status/linux.md)