Method Cancel

fetch.go:167–179

Cancel closes the Queue and drains the pending commands without processing them, allowing for a fast "stop immediately"-ish operation.

()

// Cancel closes the Queue and drains the pending commands without processing
// them, allowing for a fast "stop immediately"-ish operation.
func (q *Queue) Cancel() error {
	select {
	case <-q.cancelled:
		// already cancelled, no-op
		return nil
	default:
		// mark the queue as cancelled
		close(q.cancelled)
		// Close the Queue, that will wait for pending commands to drain
		// will unblock any callers waiting on q.Block
		return q.Close()
	}
}

// Send enqueues a Command into the Fetcher. If the Queue has been closed, it
// returns ErrQueueClosed. The Command's URL must have a Host.