breaker

type Acceptable func(err error) bool

type Breaker interface {
	// Name returns the name of the Breaker.
	Name() string

	// Allow checks if the request is allowed.
	// If allowed, a promise will be returned, the caller needs to call promise.Accept()
	// on success, or call promise.Reject() on failure.
	// If not allow, ErrServiceUnavailable will be returned.
	Allow() (Promise, error)
}

type Option func(breaker *circuitBreaker)

type Promise interface {
	// Accept tells the Breaker that the call is successful.
	Accept()
	// Reject tells the Breaker that the call is failed.
	Reject(reason string)
}