Handler guarantees execution of notifications after a critical section (the function passed to a Run method), even in the presence of process termination. It guarantees exactly once invocation of the provided notify functions.
type Handler struct {
// contains filtered or unexported fields
}
func Chain(handler *Handler, notify ...func()) *Handler
Chain creates a new handler that invokes all notify functions when the critical section exits and then invokes the optional handler's notifications. This allows critical sections to be nested without losing exactly once invocations. Notify functions can invoke any cleanup needed but should not exit (which is the responsibility of the parent handler).
func New(final func(os.Signal), notify ...func()) *Handler
New creates a new handler that guarantees all notify functions are run after the critical section exits (or is interrupted by the OS), then invokes the final handler. If no final handler is specified, the default final is `os.Exit(1)`. A handler can only be used for one critical section.
func (h *Handler) Close()
Close executes all the notification handlers if they have not yet been executed.
func (h *Handler) Run(fn func() error) error
Run ensures that any notifications are invoked after the provided fn exits (even if the process is interrupted by an OS termination signal). Notifications are only invoked once per Handler instance, so calling Run more than once will not behave as the user expects.
func (h *Handler) Signal(s os.Signal)
Signal is called when an os.Signal is received, and guarantees that all notifications are executed, then the final handler is executed. This function should only be called once per Handler instance.