room_tunnel.py

@app.cls(concurrency_limit=1, allow_concurrent_inputs=1)
class RoomProvisioner:
    project_id: str = modal.parameter()
    room_name: str = modal.parameter()

    sandbox = None

    @modal.web_endpoint()
    def lookup(self):
        
        if self.sandbox != None:
            
            if self.sandbox.poll() != None:

                self.sandbox = None
            
            else:
                return {
                    "url" : self.sandbox.tunnels()[8080].url
                }

        room = modal.App.lookup("room-server", create_if_missing=True)

        sb = None

        for s in modal.Sandbox.list(app_id=room.app_id, tags={"project_id":self.project_id, "room_name":self.room_name}):
            sb = s

        if sb != None:
            self.sandbox = sb
        else:
            sb = modal.Sandbox.create("python3","cli.py",
                app=room,
                workdir="/src",
                image=image,
                secrets=[
                    modal.Secret.from_name("custom-secret")
                ],
                encrypted_ports=[8080]
                )
            sb.set_tags(
            tags={
                "project_id": self.project_id,
                "room_name": self.room_name
            })

            self.sandbox = sb


        return {
            "url" : sb.tunnels()[8080].url
        }