diff --git a/tardis/src/basic/tracing.rs b/tardis/src/basic/tracing.rs
index a6e7c07a..0fb3e62f 100644
--- a/tardis/src/basic/tracing.rs
+++ b/tardis/src/basic/tracing.rs
@@ -3,10 +3,10 @@ use std::sync::Once;
 use crate::basic::result::TardisResult;
 use crate::config::config_dto::LogConfig;
 
-use crate::TARDIS_INST;
-
 #[allow(unused_imports)]
 use crate::consts::*;
+use crate::TARDIS_INST;
+pub use tracing_subscriber::filter::Directive;
 use tracing_subscriber::layer::Layered;
 use tracing_subscriber::util::SubscriberInitExt;
 use tracing_subscriber::EnvFilter;
diff --git a/tardis/src/web/web_resp.rs b/tardis/src/web/web_resp.rs
index 484baf49..11782492 100644
--- a/tardis/src/web/web_resp.rs
+++ b/tardis/src/web/web_resp.rs
@@ -131,5 +131,18 @@ where
     pub records: Vec<T>,
 }
 
-#[derive(Object, Deserialize, Serialize, Clone, Debug, Default, Copy)]
+#[derive(Object, Serialize, Clone, Debug, Default, Copy)]
+/// This `Void` is for represent an empty value.
+/// Any value can be deserialized as `Void`.
+/// Void will be serialized as json's `null`.
 pub struct Void;
+impl<'de> Deserialize<'de> for Void {
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: serde::Deserializer<'de>,
+    {
+        // ignore this value whatever
+        let _ = deserializer.deserialize_any(serde::de::IgnoredAny)?;
+        Ok(Void)
+    }
+}