Seed math/rand more efficiently

lib/rand.go

@@ -0,0 +1,34 @@
+package lib
+
+import (
+	crand "crypto/rand"
+	"math"
+	"math/big"
+	"math/rand"
+	"sync"
+
+	log "github.com/sirupsen/logrus"
+)
+
+var (
+	once sync.Once
+)
+
+// SeedMathRand Credit: https://github.com/hashicorp/consul/blob/main/lib/rand.go
+func SeedMathRand() {
+	var (
+		n   *big.Int
+		err error
+	)
+
+	once.Do(func() {
+		n, err = crand.Int(crand.Reader, big.NewInt(math.MaxInt64))
+		if err != nil {
+			log.Errorf("cannot seed math/rand: %s", err)
+		}
+
+		log.Debugf("seeding math/rand %+v", n.Int64())
+
+		rand.Seed(n.Int64())
+	})
+}