Add util

util/backoff/backoff.go

@@ -0,0 +1,14 @@
+// Package backoff provides backoff functionality
+package backoff
+
+import (
+	"math"
+	"time"
+)
+
+func Do(attempts int) time.Duration {
+	if attempts == 0 {
+		return time.Duration(0)
+	}
+	return time.Duration(math.Pow(10, float64(attempts))) * time.Millisecond
+}