diff --git a/src/api/helper.rs b/src/api/helper.rs
index 11420da..5d99748 100644
--- a/src/api/helper.rs
+++ b/src/api/helper.rs
@@ -1,5 +1,5 @@
 use crate::feed::Message;
-use crate::rpc::{BodyType, RequestNo, RpcStream, RpcType};
+use crate::rpc::{Body,BodyType, RequestNo, RpcStream, RpcType};
 use async_std::io::{Read, Write};
 use serde_json;
 
@@ -245,6 +245,10 @@ impl ApiMethod {
             _ => None,
         }
     }
+    pub fn from_rpc_body(body : &Body) -> Option<Self> {
+        let selector = body.name.iter().map(|v| v.as_str()).collect::<Vec<_>>();
+        Self::from_selector(&selector)
+    }
 }
 
 pub struct ApiHelper<R: Read + Unpin, W: Write + Unpin> {
diff --git a/src/feed/message.rs b/src/feed/message.rs
index d7e7bac..d23109f 100644
--- a/src/feed/message.rs
+++ b/src/feed/message.rs
@@ -52,7 +52,7 @@ impl AsRef<[u8]> for MessageId {
     }
 }
 
-#[derive(Debug, Deserialize)]
+#[derive(Debug, Deserialize, Clone)]
 pub struct Message {
     pub value: serde_json::Value,
 }
diff --git a/src/rpc/stream.rs b/src/rpc/stream.rs
index 7e5015f..b448f6d 100644
--- a/src/rpc/stream.rs
+++ b/src/rpc/stream.rs
@@ -21,7 +21,7 @@ pub enum BodyType {
     JSON,
 }
 
-#[derive(Deserialize)]
+#[derive(Debug,Deserialize)]
 pub struct Body {
     pub name: Vec<String>,
     #[serde(rename = "type")]
@@ -127,6 +127,7 @@ pub struct RpcStream<R: io::Read + Unpin, W: io::Write + Unpin> {
     req_no: RequestNo,
 }
 
+#[derive(Debug)]
 pub enum RecvMsg {
     RpcRequest(Body),
     RpcResponse(BodyType, Vec<u8>),