var (
	// ObjectCountNotFoundErr is returned when the object count for
	// a given resource is not being tracked.
	ObjectCountNotFoundErr = errors.New("object count not found for the given resource")

	// ObjectCountStaleErr is returned when the object count for a
	// given resource has gone stale due to transient failures.
	ObjectCountStaleErr = errors.New("object count has gone stale for the given resource")
)

type StorageObjectCountTracker interface {
	// Set is invoked to update the current number of total
	// objects for the given resource
	Set(string, int64)

	// Get returns the total number of objects for the given resource.
	// The following errors are returned:
	//  - if the count has gone stale for a given resource due to transient
	//    failures ObjectCountStaleErr is returned.
	//  - if the given resource is not being tracked then
	//    ObjectCountNotFoundErr is returned.
	Get(string) (int64, error)
}

type WorkEstimate struct {
	// Seats represents the number of seats associated with this request
	Seats uint

	// AdditionalLatency specifies the additional duration the seats allocated
	// to this request must be reserved after the given request had finished.
	// AdditionalLatency should not have any impact on the user experience, the
	// caller must not experience this additional latency.
	AdditionalLatency time.Duration
}

type WorkEstimatorFunc func(*http.Request) WorkEstimate