[slightlyoff/ServiceWorker] consider exposing self.clients on window and other worker globals (#955)

The `Clients` and `Client` interfaces are pretty close to being a generic API for querying and manipulating windows/workers in the browser.  Its nicer than things like `window.open()` though because its designed to be async and is less permissive in what the caller can do.

I think we should consider exposing `Clients` and `Client` interfaces on windows and other worker globals.  Perhaps as `navigator.clients` to avoid name collisions.

To do this we would need to specialize the interface for service workers a bit, though:

1. `Clients.claim()` does not make sense outside of a service worker global.
2. `Client.postMessage()` currently goes to `navigator.serviceWorker.onmessage`.  This would need to still happen for service worker globals.  When used from other globals we would need to fire the event at a different target.  Perhaps `navigator.clients.onmessage`.
3. The behavior of `clients.matchAll()` only returning controlled Client objects only makes sense for service worker globals.  Other globals should probably imply `includeUncontrolled:true`.

All same-origin restrictions would still apply.  I assume we would only support this in secure contexts.

If we think we might want to do this it would be nice to do it sooner rather than later.  Over time we will probably have more service worker specific features creep into the API.

-- 
You are receiving this because you are subscribed to this thread.
Reply to this email directly or view it on GitHub:
https://github.com/slightlyoff/ServiceWorker/issues/955