package semaphore

import "github.com/eapache/go-resiliency/semaphore"

Package semaphore implements the semaphore resiliency pattern for Go.

Index ¶

• Variables
• type Semaphore
• func New(tickets int, timeout time.Duration) *Semaphore
• func (s *Semaphore) Acquire() error
• func (s *Semaphore) Release()

Examples ¶

• Semaphore

Variables ¶

var ErrNoTickets = errors.New("could not aquire semaphore ticket")

ErrNoTickets is the error returned by Acquire when it could not acquire a ticket from the semaphore within the configured timeout.

Types ¶

type Semaphore ¶

type Semaphore struct {
	// contains filtered or unexported fields
}

Semaphore implements the semaphore resiliency pattern

{
	sem := New(3, 1*time.Second)

	for i := 0; i < 10; i++ {
		go func() {
			if err := sem.Acquire(); err != nil {
				return //could not acquire semaphore
			}
			defer sem.Release()

			// do something semaphore-guarded
		}()
	}
}

func New ¶

func New(tickets int, timeout time.Duration) *Semaphore

New constructs a new Semaphore with the given ticket-count and timeout.

func (*Semaphore) Acquire ¶

func (s *Semaphore) Acquire() error

Acquire tries to acquire a ticket from the semaphore. If it can, it returns nil. If it cannot after "timeout" amount of time, it returns ErrNoTickets. It is safe to call Acquire concurrently on a single Semaphore.

func (*Semaphore) Release ¶

func (s *Semaphore) Release()

Release releases an acquired ticket back to the semaphore. It is safe to call Release concurrently on a single Semaphore. It is an error to call Release on a Semaphore from which you have not first acquired a ticket.

Source Files ¶

semaphore.go