WebRTC support on Linux

[ken0x0a]

I tested only on macOS.
It might already work on other platforms.

Is your feature request related to a problem? Please describe.
I want to use WebRTC

Describe the solution you'd like
I don't have any preference.
I just want to use WebRTC.

Describe alternatives you've considered

• With system webbrowser (doesn't work on macOS)

  Notification.requestPermission() // => undefined
  navigator.mediaDevices // => undefined

• Using another process
  I don't know any library to use WebRTC with VideoUI on desktop 😭

Additional context

It seems, the cause of this issue is this https://forums.developer.apple.com/thread/88052

And, the following might solve this issue on macOS (not tested).
https://bugs.webkit.org/show_bug.cgi?id=208667#c17

---

There are similar issues in other repositories.

• [Question] Permissions branchseer/DeskGap#26 (comment)
  (someone mentioned "WkWebView's getUserMedia functionality is disabled, when embedded")
• Webrtc Camera and Audio not available on MacOS Webview webview/webview#368

[nothingismagick]

So i found these additions to the Info.plist

	<key>NSCameraUsageDescription</key>
	<string>$(PRODUCT_NAME) Requires camera access in order to capture and transmit video</string>
	<key>NSMicrophoneUsageDescription</key>
	<string>$(PRODUCT_NAME) Requires microphone access in order to capture and transmit audio</string>

https://developer.apple.com/documentation/bundleresources/information_property_list/nscamerausagedescription?language=objc
https://developer.apple.com/documentation/bundleresources/information_property_list/nsmicrophoneusagedescription?language=objc

@rajivshah3

[nothingismagick]

regarding notifications @ken0x0a - we merged a cross-platform notification API: tauri-apps/tauri#505

It will land in the next release.

[nothingismagick]

I am wondering if we will have to roll our own:
libp2p/rust-libp2p#1066

[nothingismagick]

Well, I believe that our new custom protocol allows for the secure context on all platforms. Still, we have not proven this to work, so am moving this issue over to WRY for tracking there.

[wusyong]

Maybe this also belongs to #81?

[nklayman]

WebRTC also is not supported by Webkit2GTK. It technically doesn't require permissions to work, but it's most commonly used with a webcam/mic input and those require permissions.

[lemarier]

macOS update

The runtime requires some permissions. Adding an embed PLIST to the runtime fixed the issue for me.

You can give it a try with embed_plist

Sample PLIST

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
	<key>NSCameraUsageDescription</key>
	<string>Request camera access for WebRTC</string>
	<key>NSMicrophoneUsageDescription</key>
	<string>Request microphone access for WebRTC</string>
</dict>
</plist>

Test app

#[cfg(target_os = "macos")]
embed_plist::embed_info_plist!("Info.plist");

fn main() -> wry::Result<()> {
  use wry::{
    application::{
      event::{Event, StartCause, WindowEvent},
      event_loop::{ControlFlow, EventLoop},
      window::WindowBuilder,
    },
    webview::WebViewBuilder,
  };

  let event_loop = EventLoop::new();
  let window = WindowBuilder::new()
    .with_title("Hello World")
    .build(&event_loop)
    .unwrap();
  let _webview = WebViewBuilder::new(window)
    .unwrap()
    .with_url("https://test.webrtc.org/")?
    .build()?;

  event_loop.run(move |event, _, control_flow| {
    *control_flow = ControlFlow::Poll;

    match event {
      Event::NewEvents(StartCause::Init) => println!("Wry application started!"),
      Event::WindowEvent {
        event: WindowEvent::CloseRequested,
        ..
      } => *control_flow = ControlFlow::Exit,
      _ => (),
    }
  });
}

Also, seems to works only over HTTPS, so doesn't work for custom protocol, so I think the wry job is pretty much done, only require the custom protocol support who I think should be moved to another issue.

Tauri should give the possibility to inject a PLIST at runtime for development. For bundled app, we already generate a plist, so maybe we should add it as a configuration object to request microphone, webcam access, so we could inject it automatically.

Edit: Looks like I've been able to get custom protocol to work. We need to make sure to use the host localhost in our custom protocol. So for example, instead of using wry:// as the entry point, we should use wry://localhost/, this way content, is processed as HTTPS.