github.com/facebookincubator/go-belt@v0.0.0-20230703220935-39cd348f1a38/tool/experimental/tracer/hook.go

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package tracer

// Hook is executed right before sending a Span (to some backend).
type Hook interface {
	// ProcessSpan is the main method of a Hook. It is executed before sending
	// a Span (to some backend). If it returns false then any further processing
	// and sending of the Span is cancelled.
	ProcessSpan(Span) bool

	// Flush just gracefully empties all the queues (if there are any).
	Flush()
}

// Hooks is a collection of multiple Hook-s.
type Hooks []Hook

var _ Hook = (Hooks)(nil)

// ProcessSpan implements Hook.
func (s Hooks) ProcessSpan(span Span) bool {
	for _, hook := range s {
		if !hook.ProcessSpan(span) {
			return false
		}
	}
	return true
}

// Flush implements Hook.
func (s Hooks) Flush() {
	for _, hook := range s {
		hook.Flush()
	}
}