server

type Component func(stop <-chan struct{}) error

type Instance interface {
	// Start this Server. Any components that were already added
	// will be run immediately. If any error is returned,
	// Start will terminate and return the error immediately.
	//
	// Once all startup components have been run, starts a polling
	// loop to continue monitoring for new components and returns nil.
	Start(stop <-chan struct{}) error

	// RunComponent adds the given component to the server's run queue.
	RunComponent(name string, t Component)

	// RunComponentAsync runs the given component asynchronously.
	RunComponentAsync(name string, t Component)

	// RunComponentAsyncAndWait runs the given component asynchronously. When
	// the server Instance is shutting down, it will wait for the component
	// to complete before exiting.
	// Note: this is best effort; a process can die at any time.
	RunComponentAsyncAndWait(name string, t Component)

	// Wait for this server Instance to shutdown.
	Wait()
}