chore: make stub of the Tauri client for macOS (#3977)

This would allow me to fix compile / check / fmt errors from macOS CI
runners locally, e.g.
https://github.com/firezone/firezone/pull/3920#discussion_r1513357337

It can't sign in or start connlib, but it shows the GUI


![image](https://github.com/firezone/firezone/assets/13400041/5307b66e-9874-4fe5-a6a6-43082dd6e385)

---------

Signed-off-by: Reactor Scram <ReactorScram@users.noreply.github.com>
Co-authored-by: User <user@Users-MacBook-Pro.local>
Co-authored-by: Jamil <jamilbk@users.noreply.github.com>

rust/gui-client/src-tauri/Cargo.toml

@@ -57,6 +57,11 @@ dirs = "5.0.1"
 # Used for infinite `pending` on not-yet-implemented functions
 futures = "0.3.30"
 
+[target.'cfg(target_os = "macos")'.dependencies]
+dirs = "5.0.1"
+# Used for infinite `pending` on not-implemented functions
+futures = "0.3.30"
+
 [target.'cfg(target_os = "windows")'.dependencies]
 tauri-winrt-notification = "0.1.3"
 windows-implement = "0.53.0"

rust/gui-client/src-tauri/src/client/deep_link.rs

@@ -11,6 +11,11 @@ pub(crate) const FZ_SCHEME: &str = "firezone-fd0020211111";
 #[path = "deep_link/linux.rs"]
 mod imp;
 
+// Stub only
+#[cfg(target_os = "macos")]
+#[path = "deep_link/macos.rs"]
+mod imp;
+
 #[cfg(target_os = "windows")]
 #[path = "deep_link/windows.rs"]
 mod imp;

rust/gui-client/src-tauri/src/client/deep_link/macos.rs

@@ -0,0 +1,27 @@
+//! Placeholder
+
+use super::Error;
+use connlib_shared::control::SecureUrl;
+use secrecy::Secret;
+
+pub(crate) struct Server {}
+
+impl Server {
+    pub(crate) fn new() -> Result<Self, Error> {
+        tracing::warn!("This is not the actual Mac client");
+        tracing::trace!(scheme = super::FZ_SCHEME, "prevents dead code warning");
+        Ok(Self {})
+    }
+
+    pub(crate) async fn accept(self) -> Result<Secret<SecureUrl>, Error> {
+        futures::future::pending().await
+    }
+}
+
+pub(crate) async fn open(_url: &url::Url) -> Result<(), Error> {
+    Ok(())
+}
+
+pub(crate) fn register() -> Result<(), Error> {
+    Ok(())
+}

rust/gui-client/src-tauri/src/client/elevation.rs

@@ -14,6 +14,20 @@ mod imp {
     }
 }
 
+// Stub only
+#[cfg(target_os = "macos")]
+mod imp {
+    use anyhow::Result;
+
+    pub(crate) fn check() -> Result<bool> {
+        Ok(true)
+    }
+
+    pub(crate) fn elevate() -> Result<()> {
+        unimplemented!()
+    }
+}
+
 #[cfg(target_os = "windows")]
 mod imp {
     use crate::client::wintun_install;

rust/gui-client/src-tauri/src/client/gui.rs

@@ -25,6 +25,11 @@ mod system_tray_menu;
 #[path = "gui/os_linux.rs"]
 mod os;
 
+// Stub only
+#[cfg(target_os = "macos")]
+#[path = "gui/os_macos.rs"]
+mod os;
+
 #[cfg(target_os = "windows")]
 #[path = "gui/os_windows.rs"]
 mod os;

rust/gui-client/src-tauri/src/client/gui/os_macos.rs

@@ -0,0 +1,17 @@
+//! This file is a stub only to do Tauri UI dev natively on a Mac.
+use super::{ControllerRequest, CtlrTx, Error};
+
+/// Show a notification in the bottom right of the screen
+pub(crate) fn show_notification(_title: &str, _body: &str) -> Result<(), Error> {
+    unimplemented!()
+}
+
+/// Show a notification that signals `Controller` when clicked
+pub(crate) fn show_clickable_notification(
+    _title: &str,
+    _body: &str,
+    _tx: CtlrTx,
+    _req: ControllerRequest,
+) -> Result<(), Error> {
+    unimplemented!()
+}

rust/gui-client/src-tauri/src/client/known_dirs.rs

@@ -9,7 +9,7 @@
 
 pub(crate) use imp::{device_id, logs, runtime, session, settings};
 
-#[cfg(target_os = "linux")]
+#[cfg(any(target_os = "linux", target_os = "macos"))]
 mod imp {
     use connlib_shared::BUNDLE_ID;
     use std::path::PathBuf;

rust/gui-client/src-tauri/src/client/network_changes.rs

@@ -2,6 +2,10 @@
 #[path = "network_changes/linux.rs"]
 mod imp;
 
+#[cfg(target_os = "macos")]
+#[path = "network_changes/macos.rs"]
+mod imp;
+
 #[cfg(target_os = "windows")]
 #[path = "network_changes/windows.rs"]
 mod imp;

rust/gui-client/src-tauri/src/client/network_changes/macos.rs

@@ -0,0 +1,31 @@
+//! Placeholder
+
+use anyhow::Result;
+
+#[derive(thiserror::Error, Debug)]
+pub(crate) enum Error {}
+
+pub(crate) fn run_debug() -> Result<()> {
+    unimplemented!()
+}
+
+pub(crate) fn check_internet() -> Result<bool> {
+    tracing::error!("This is not the real macOS client, so `network_changes` is not implemented");
+    Ok(true)
+}
+
+pub(crate) struct Worker {}
+
+impl Worker {
+    pub(crate) fn new() -> Result<Self> {
+        Ok(Self {})
+    }
+
+    pub(crate) fn close(&mut self) -> Result<()> {
+        Ok(())
+    }
+
+    pub(crate) async fn notified(&self) {
+        futures::future::pending().await
+    }
+}

rust/gui-client/src-tauri/src/client/resolvers.rs

@@ -14,6 +14,11 @@ pub fn get() -> Result<Vec<IpAddr>, Error> {
     todo!()
 }
 
+#[cfg(target_os = "macos")]
+pub fn get() -> Result<Vec<IpAddr>, Error> {
+    todo!()
+}
+
 #[cfg(target_os = "windows")]
 pub fn get() -> Result<Vec<IpAddr>, Error> {
     Ok(ipconfig::get_adapters()?

rust/gui-client/src-tauri/src/client/updates.rs

@@ -65,12 +65,16 @@ const LATEST_RELEASE_API_URL: &str =
 /// <https://docs.github.com/en/rest/about-the-rest-api/api-versions?apiVersion=2022-11-28>
 const GITHUB_API_VERSION: &str = "2022-11-28";
 
-/// The name of the Windows MSI asset.
+/// The name of the Windows MSI / Linux AppImage or deb asset.
 ///
-/// This ultimately comes from `cd.yml`, `git grep WCPYPXZF`
+/// These ultimately come from `cd.yml`, `git grep WCPYPXZF`
 #[cfg(target_os = "linux")]
 const ASSET_NAME: &str = "firezone-linux-gui-client_amd64.AppImage";
 
+/// Unused - The Tauri client is not supported for macOS
+#[cfg(target_os = "macos")]
+const ASSET_NAME: &str = "firezone-mac-unused-client_aarch64.dmg";
+
 #[cfg(target_os = "windows")]
 const ASSET_NAME: &str = "firezone-windows-client-x64.msi";
 

rust/gui-client/src-tauri/src/main.rs

@@ -3,20 +3,8 @@
 // Prevents additional console window on Windows in release, DO NOT REMOVE!!
 #![cfg_attr(not(debug_assertions), windows_subsystem = "windows")]
 
+mod client;
+
 fn main() -> anyhow::Result<()> {
     client::run()
 }
-
-#[cfg(target_os = "linux")]
-mod client;
-
-#[cfg(target_os = "macos")]
-mod client {
-    pub(crate) fn run() -> anyhow::Result<()> {
-        println!("The GUI client does not compile on macOS yet");
-        Ok(())
-    }
-}
-
-#[cfg(target_os = "windows")]
-mod client;