contextlock

type ContextLocker ¶

type ContextLocker interface {
	sync.Locker

	// ContextLock provides exclusive control of the ContextLocker object if and
	// only if the error returned is nil. A subsequent call to Unlock or
	// ContextUnlock from any goroutine will release control of the
	// ContextLocker object.
	ContextLock(ctx context.Context) error

	// ContextUnlock releases control of the ContextLocker object. If the
	// ContextLocker has not been locked prior to this call via either Lock o
	// ContextLock, the behavior of this method is undefined, but may likely
	// panic.
	ContextUnlock(ctx context.Context) error
}

ContextLocker extends the sync.Locker interface to support two new lock/unlock methods, ContextLock and ContextUnlock. These methods perform similar operations (and are directly compatible with) the original Lock and Unlock methods, but accept an additional context.Context argument used to terminate lock acquisition attempts prematurely.

If the lock is not successfully acquired or released via a context-compatible method, an error will be returned describing why.

This lock interface can be used to front remote or distributed locks while using a similar interface to the local sync.Mutex-style locks. Because of this, care should be taken when selecting implementations for and adding ContextLocker acquisitions/releases to performance-critical code.

The sync.Locker interface is fully compatible with the new context-compatible ContextLocker methods. Thus, it is acceptable for a caller to call Lock then ContextUnlock, or call ContextLock then Unlock.