add: anowflake email kafka, refa: redis connectg

app/email/api/internal/utils/genCode.go

@@ -0,0 +1,16 @@
+package utils
+
+import (
+	"crypto/rand"
+	"fmt"
+	"math/big"
+)
+
+func GenCode() string {
+	n, err := rand.Int(rand.Reader, big.NewInt(1000000))
+	if err != nil {
+		return "000000"
+	}
+
+	return fmt.Sprintf("%06d", n.Int64())
+}