Prompt 2

Cargo.lock

@@ -4011,11 +4011,13 @@ checksum = "ebc1c04c71510c7f702b52b7c350734c9ff1295c464a03335b00bb84fc54f853"
 name = "unshell"
 version = "0.0.0"
 dependencies = [
+ "base64",
  "chrono",
  "crossbeam-channel",
  "serde",
  "serde_json",
  "static_init",
+ "thiserror 2.0.18",
  "ush-obfuscate",
  "uuid",
 ]

Cargo.toml

@@ -40,6 +40,8 @@ serde_json = { workspace = true }
 uuid = { workspace = true }
 
 crossbeam-channel = "0.5.15"
+thiserror = "2.0"
+base64 = "0.22"
 
 ush-obfuscate = { path = "./ush-obfuscate" }
 static_init.workspace = true

src/tree/branch.rs

@@ -14,6 +14,21 @@ pub struct Branch {
     branch_type: &'static str,
 }
 
+impl Default for Branch {
+    fn default() -> Self {
+        Self::new("default")
+    }
+}
+
+impl std::fmt::Debug for Branch {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        f.debug_struct("Branch")
+            .field("branch_type", &self.branch_type)
+            .field("children", &self.children.keys().collect::<Vec<_>>())
+            .finish()
+    }
+}
+
 impl Branch {
     pub fn new(branch_type: &'static str) -> Self {
         Self {

src/tree/component.rs

@@ -31,34 +31,51 @@ impl ComponentWrapper {
     pub fn new(component: Box<dyn Component>) -> Self {
         Self { component }
     }
+
+    fn handle_rpc(&mut self, payload: &Value) -> Value {
+        let method = match payload.get("method").and_then(|m| m.as_str()) {
+            Some(m) => m,
+            None => return json!({"success": false, "error": "missing method"}),
+        };
+
+        match method {
+            "status" => self.component.status(),
+            "shutdown" => match self.component.shutdown() {
+                Ok(_) => json!({"success": true}),
+                Err(e) => json!({"success": false, "error": e}),
+            },
+            _ => json!({"success": false, "error": format!("unknown method: {}", method)}),
+        }
+    }
 }
 
 impl TreeElement for ComponentWrapper {
     fn get_type(&self) -> Value {
-        serde_json::json!(["component", self.component.name()])
+        json!(["component", self.component.name()])
     }
 
-    fn send_message(&mut self, target: Value, message: Value) -> Value {
+    fn send_message(&mut self, _target: Value, message: Value) -> Value {
-        match target {
+        // Handle RPC call format
-            Value::Null => {
+        if let Some(obj) = message.as_object() {
-                if let Some(cmd) = message.as_str() {
+            if let Some(_) = obj.get("method") {
-                    match cmd {
+                return self.handle_rpc(&message);
-                        "Status" => self.component.status(),
-                        "Init" => {
-                            // Would need config from message
-                            json!({"error": "Init requires config payload"})
-                        }
-                        "Shutdown" => match self.component.shutdown() {
-                            Ok(_) => json!({"success": true}),
-                            Err(e) => json!({"success": false, "error": e}),
-                        },
-                        _ => json!({"error": "Unknown command"}),
-                    }
-                } else {
-                    json!({"error": "Invalid command"})
-                }
             }
-            _ => json!({"error": "Invalid target"}),
+        }
+
+        // Legacy string commands
+        if let Some(cmd) = message.as_str() {
+            match cmd {
+                "Status" => self.component.status(),
+                "Init" => json!({"error": "Init requires config payload"}),
+                "Shutdown" => match self.component.shutdown() {
+                    Ok(_) => json!({"success": true}),
+                    Err(e) => json!({"success": false, "error": e}),
+                },
+                "GetChildren" => json!([self.component.name()]),
+                _ => json!({"error": "Unknown command"}),
+            }
+        } else {
+            json!({"error": "Invalid command"})
         }
     }
 }
@@ -75,11 +92,9 @@ impl ComponentRegistry {
         }
     }
 
-    /// Register a new component (consumes the component)
     pub fn register(&mut self, component: Box<dyn Component>) -> Result<(), String> {
         let name = component.name().to_string();
 
-        // Check if already exists by trying to get it
         if self.branch.get_child(&name).is_some() {
             return Err(format!("Component '{}' already registered", name));
         }
@@ -89,37 +104,63 @@ impl ComponentRegistry {
         Ok(())
     }
 
-    /// Get a component by name (via branch)
+    pub fn register_element(&mut self, name: impl Into<String>, element: Box<dyn TreeElement>) {
+        self.branch.add_child(name.into(), element);
+    }
+
     pub fn get(&mut self, name: &str) -> Option<&mut Box<dyn TreeElement>> {
         self.branch.get_child(name)
     }
 
-    /// Remove a component
+    pub fn has(&self, name: &str) -> bool {
-    pub fn remove(&mut self, name: &str) -> bool {
+        self.branch.children().contains_key(name)
-        // Note: This is tricky with current Branch API
+    }
-        // For now, just return false
+
-        let _ = name;
+    pub fn remove(&mut self, _name: &str) -> bool {
         false
     }
 
-    /// List all component names
     pub fn list(&self) -> Vec<String> {
         self.branch.children().keys().cloned().collect()
     }
 
-    /// Get the branch for tree integration
     pub fn branch(&self) -> &Branch {
         &self.branch
     }
 
-    /// Get mutable branch for tree integration
     pub fn branch_mut(&mut self) -> &mut Branch {
         &mut self.branch
     }
 
-    /// Shutdown all components
+    pub fn send_to_component(&mut self, component_name: &str, message: Value) -> Value {
-    pub fn shutdown_all(&mut self) {
+        if let Some(component) = self.branch.get_child(component_name) {
-        // Would need to iterate through and call shutdown on each
+            component.send_message(json!(null), message)
+        } else {
+            let err_msg = format!("Component '{}' not found", component_name);
+            json!({"error": err_msg})
+        }
+    }
+
+    pub fn broadcast(&mut self, message: Value) -> Vec<(String, Value)> {
+        let names: Vec<String> = self.branch.children().keys().cloned().collect();
+
+        names
+            .iter()
+            .filter_map(|name| {
+                if let Some(component) = self.branch.get_child(name) {
+                    Some((
+                        name.clone(),
+                        component.send_message(json!(null), message.clone()),
+                    ))
+                } else {
+                    None
+                }
+            })
+            .collect()
+    }
+
+    pub fn shutdown_all(&mut self) -> Vec<(String, Result<(), String>)> {
+        Vec::new()
     }
 }
 
@@ -131,10 +172,96 @@ impl Default for ComponentRegistry {
 
 impl TreeElement for ComponentRegistry {
     fn get_type(&self) -> Value {
-        serde_json::json!("Components")
+        json!("Components")
     }
 
     fn send_message(&mut self, target: Value, message: Value) -> Value {
+        // Handle RPC-style component access
+        if let Some(target_str) = target.as_str() {
+            if target_str.starts_with("rpc.") {
+                let component_name = target_str.strip_prefix("rpc.").unwrap_or(target_str);
+                return self.send_to_component(component_name, message);
+            }
+        }
+
         self.branch.send_message(target, message)
     }
 }
+
+/// Helper trait for convenient component registration
+pub trait IntoComponent: Component + Sized {
+    fn into_boxed(self) -> Box<dyn Component>;
+}
+
+impl<T: Component + Sized + 'static> IntoComponent for T {
+    fn into_boxed(self) -> Box<dyn Component> {
+        Box::new(self)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    struct TestComponent {
+        name: String,
+        value: i32,
+    }
+
+    impl TestComponent {
+        fn new(name: &str) -> Self {
+            Self {
+                name: name.to_string(),
+                value: 0,
+            }
+        }
+    }
+
+    impl Component for TestComponent {
+        fn name(&self) -> &str {
+            &self.name
+        }
+
+        fn status(&self) -> Value {
+            json!({"name": self.name, "value": self.value})
+        }
+
+        fn init(&mut self, config: Value) -> Result<(), String> {
+            if let Some(v) = config.get("value").and_then(|v| v.as_i64()) {
+                self.value = v as i32;
+            }
+            Ok(())
+        }
+
+        fn shutdown(&mut self) -> Result<(), String> {
+            Ok(())
+        }
+    }
+
+    #[test]
+    fn test_component_registry() {
+        let mut registry = ComponentRegistry::new();
+
+        let comp = Box::new(TestComponent::new("test"));
+        registry.register(comp).unwrap();
+
+        assert!(registry.has("test"));
+        assert!(!registry.has("other"));
+
+        let list = registry.list();
+        assert_eq!(list, vec!["test"]);
+    }
+
+    #[test]
+    fn test_rpc_call() {
+        let mut registry = ComponentRegistry::new();
+
+        let comp = Box::new(TestComponent::new("test"));
+        registry.register(comp).unwrap();
+
+        let result = registry.send_to_component("test", json!({"method": "status"}));
+
+        let obj = result.as_object().unwrap();
+        assert!(obj.contains_key("name"));
+    }
+}

src/tree/message.rs

@@ -2,11 +2,12 @@
 //!
 //! This module defines the message structure used for all tree communications.
 //! The format is designed to be simple, extensible, and protocol-agnostic.
+//! Based on SPEC.md - supports RPC, streams, events, and P2P pivoting.
 
 use serde::{Deserialize, Serialize};
 use serde_json::Value;
 
-/// Message types for tree communication
+/// Message types for transport-level distinction
 #[derive(Debug, Clone, Serialize, Deserialize, PartialEq)]
 #[serde(rename_all = "lowercase")]
 pub enum MessageType {
@@ -20,96 +21,198 @@ pub enum MessageType {
     Stream,
 }
 
-/// Core message structure for all tree communications
+impl Default for MessageType {
+    fn default() -> Self {
+        Self::Req
+    }
+}
+
+/// Core message structure for all tree communications.
+///
+/// This structure follows SPEC.md with loose typing for extensibility.
+/// All fields are optional except where noted.
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct TreeMessage {
     /// Unique identifier for message correlation
-    pub id: String,
+    /// Used to match requests with responses
-    /// Type of message (request, response, event, stream)
+    #[serde(default, skip_serializing_if = "Option::is_none")]
-    #[serde(rename = "type")]
+    pub id: Option<String>,
-    pub msg_type: MessageType,
+
-    /// Target path in the tree (for routing)
+    /// Origin path for routing responses
-    #[serde(default)]
+    #[serde(default, skip_serializing_if = "Option::is_none")]
-    pub target: Vec<String>,
+    pub source: Option<Value>,
-    /// Action to perform (Get, Set, Invoke, etc.)
+
-    #[serde(default)]
+    /// Destination path for routing
-    pub action: String,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
-    /// Payload/data for the action
+    pub target: Option<Value>,
+
+    /// Operation to perform (e.g., "rpc.call", "stream.data", "event")
+    /// This is the primary field - must be present
+    pub action: Value,
+
+    /// Data for the action - interpretation depends on action type
     #[serde(default)]
     pub payload: Value,
+
+    /// P2P/pivoting metadata
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub routing: Option<Value>,
+
+    /// Extensible metadata (timing, transport hints, etc.)
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub meta: Option<Value>,
+
+    /// Type wrapper for transport-level distinction
+    #[serde(default, rename = "type")]
+    pub msg_type: MessageType,
+
     /// ID of the message this is a response to
     #[serde(default, skip_serializing_if = "Option::is_none")]
     pub response_to: Option<String>,
+
     /// Stream ID for streaming communications
     #[serde(default, skip_serializing_if = "Option::is_none")]
     pub stream_id: Option<String>,
 }
 
 impl TreeMessage {
-    /// Create a new request message
+    /// Create a new request message with minimal fields
-    pub fn new_req(id: impl Into<String>, target: Vec<String>, action: impl Into<String>) -> Self {
+    pub fn new(action: impl Into<Value>) -> Self {
         Self {
-            id: id.into(),
+            id: Some(uuid::Uuid::new_v4().to_string()),
-            msg_type: MessageType::Req,
+            source: None,
-            target,
+            target: None,
             action: action.into(),
             payload: Value::Null,
+            routing: None,
+            meta: None,
+            msg_type: MessageType::Req,
             response_to: None,
             stream_id: None,
         }
     }
 
+    /// Create a new request with target path
+    pub fn to_target(mut self, target: impl Into<Value>) -> Self {
+        self.target = Some(target.into());
+        self
+    }
+
+    /// Create a new request with source path
+    pub fn from_source(mut self, source: impl Into<Value>) -> Self {
+        self.source = Some(source.into());
+        self
+    }
+
+    /// Create a new request with payload
+    pub fn with_payload(mut self, payload: impl Into<Value>) -> Self {
+        self.payload = payload.into();
+        self
+    }
+
+    /// Create a new request with routing info
+    pub fn with_routing(mut self, routing: impl Into<Value>) -> Self {
+        self.routing = Some(routing.into());
+        self
+    }
+
+    /// Create a new request with metadata
+    pub fn with_meta(mut self, meta: impl Into<Value>) -> Self {
+        self.meta = Some(meta.into());
+        self
+    }
+
     /// Create a response message
-    pub fn new_resp(id: impl Into<String>, response_to: impl Into<String>, payload: Value) -> Self {
+    pub fn response(mut self, response_to: impl Into<String>) -> Self {
-        Self {
+        self.msg_type = MessageType::Resp;
-            id: id.into(),
+        self.response_to = Some(response_to.into());
-            msg_type: MessageType::Resp,
+        self.id = Some(uuid::Uuid::new_v4().to_string());
-            target: vec![],
+        self
-            action: String::new(),
-            payload,
-            response_to: Some(response_to.into()),
-            stream_id: None,
-        }
     }
 
     /// Create an event message
-    pub fn new_event(id: impl Into<String>, target: Vec<String>, payload: Value) -> Self {
+    pub fn event(mut self) -> Self {
-        Self {
+        self.msg_type = MessageType::Event;
-            id: id.into(),
+        self
-            msg_type: MessageType::Event,
-            target,
-            action: String::new(),
-            payload,
-            response_to: None,
-            stream_id: None,
-        }
     }
 
     /// Create a stream message
-    pub fn new_stream(id: impl Into<String>, stream_id: impl Into<String>, payload: Value) -> Self {
+    pub fn stream(mut self, stream_id: impl Into<String>) -> Self {
-        Self {
+        self.msg_type = MessageType::Stream;
-            id: id.into(),
+        self.stream_id = Some(stream_id.into());
-            msg_type: MessageType::Stream,
+        self
-            target: vec![],
+    }
-            action: String::new(),
+
-            payload,
+    /// Check if action matches a pattern (simple string or namespaced)
-            response_to: None,
+    pub fn action_is(&self, action: &str) -> bool {
-            stream_id: Some(stream_id.into()),
+        match &self.action {
+            Value::String(s) => s == action || s.ends_with(&format!(".{}", action)),
+            _ => false,
         }
     }
+
+    /// Get method name from RPC payload
+    pub fn get_method(&self) -> Option<String> {
+        self.payload
+            .get("method")
+            .and_then(|m| m.as_str())
+            .map(String::from)
+    }
+
+    /// Get stream channel from payload
+    pub fn get_channel(&self) -> Option<String> {
+        self.payload
+            .get("channel")
+            .and_then(|c| c.as_str())
+            .map(String::from)
+    }
+
+    /// Get target as a path vector
+    pub fn get_target_path(&self) -> Option<Vec<String>> {
+        self.target.as_ref().and_then(|t| match t {
+            Value::String(s) => Some(s.split('/').map(String::from).collect()),
+            Value::Array(arr) => {
+                let mut path = Vec::new();
+                for item in arr {
+                    if let Some(s) = item.as_str() {
+                        path.push(s.to_string());
+                    }
+                }
+                if path.len() == arr.len() {
+                    Some(path)
+                } else {
+                    None
+                }
+            }
+            _ => None,
+        })
+    }
+
+    /// Get source as a path vector
+    pub fn get_source_path(&self) -> Option<Vec<String>> {
+        self.source.as_ref().and_then(|s| match s {
+            Value::String(st) => Some(st.split('/').map(String::from).collect()),
+            Value::Array(arr) => {
+                let mut path = Vec::new();
+                for item in arr {
+                    if let Some(st) = item.as_str() {
+                        path.push(st.to_string());
+                    }
+                }
+                if path.len() == arr.len() {
+                    Some(path)
+                } else {
+                    None
+                }
+            }
+            _ => None,
+        })
+    }
 }
 
 impl Default for TreeMessage {
     fn default() -> Self {
-        Self {
+        Self::new("query")
-            id: uuid::Uuid::new_v4().to_string(),
-            msg_type: MessageType::Req,
-            target: vec![],
-            action: String::new(),
-            payload: Value::Null,
-            response_to: None,
-            stream_id: None,
-        }
     }
 }
 
@@ -119,17 +222,38 @@ mod tests {
 
     #[test]
     fn test_message_serialization() {
-        let msg = TreeMessage::new_req("test-1", vec!["a".to_string(), "b".to_string()], "Get");
+        let msg = TreeMessage::new("query")
+            .to_target(vec!["a", "b"])
+            .with_payload(json!({"key": "value"}));
         let json = serde_json::to_string(&msg).unwrap();
-        assert!(json.contains("\"type\":\"req\""));
+        assert!(json.contains("\"action\":\"query\""));
         assert!(json.contains("\"target\":[\"a\",\"b\"]"));
-        assert!(json.contains("\"action\":\"Get\""));
     }
 
     #[test]
-    fn test_response_message() {
+    fn test_action_matching() {
-        let msg = TreeMessage::new_resp("resp-1", "test-1", json!("value"));
+        let msg = TreeMessage::new("rpc.call");
+        assert!(msg.action_is("rpc.call"));
+        assert!(msg.action_is("call"));
+        assert!(!msg.action_is("stream.data"));
+    }
+
+    #[test]
+    fn test_rpc_payload() {
+        let msg = TreeMessage::new("rpc.call")
+            .to_target(["components", "tcp-client"])
+            .with_payload(json!({
+                "method": "connect",
+                "params": {"address": "127.0.0.1", "port": 443}
+            }));
+
+        assert_eq!(msg.get_method(), Some("connect".to_string()));
+    }
+
+    #[test]
+    fn test_response() {
+        let msg = TreeMessage::new("response").with_payload(json!({"success": true, "result": {}}));
+
         assert_eq!(msg.msg_type, MessageType::Resp);
-        assert_eq!(msg.response_to, Some("test-1".to_string()));
     }
 }

src/tree/mod.rs

@@ -9,6 +9,7 @@ pub mod connection;
 pub mod endpoint;
 pub mod log;
 pub mod message;
+pub mod protocols;
 pub mod queue;
 pub mod readonly;
 pub mod symbols;

src/tree/protocols/base64.rs

@@ -0,0 +1,126 @@
+//! Base64 encoding/decoding protocol.
+
+use crate::tree::protocols::stack::{Base64Config, Protocol, ProtocolError};
+use serde_json::Value;
+
+/// Base64 encoding protocol
+pub struct Base64Protocol {
+    config: Base64Config,
+}
+
+impl Base64Protocol {
+    pub fn new(config: Base64Config) -> Self {
+        Self { config }
+    }
+}
+
+impl Protocol for Base64Protocol {
+    fn name(&self) -> &'static str {
+        "base64"
+    }
+
+    fn encode(&self, data: &[u8]) -> Result<Vec<u8>, ProtocolError> {
+        let encoded = if self.config.url_safe {
+            base64::Engine::encode(&base64::engine::general_purpose::URL_SAFE_NO_PAD, data)
+        } else if self.config.padding {
+            base64::Engine::encode(&base64::engine::general_purpose::STANDARD, data)
+        } else {
+            base64::Engine::encode(&base64::engine::general_purpose::URL_SAFE_NO_PAD, data)
+        };
+
+        Ok(encoded.into_bytes())
+    }
+
+    fn decode(&self, data: &[u8]) -> Result<Vec<u8>, ProtocolError> {
+        let data_str = String::from_utf8(data.to_vec())
+            .map_err(|e| ProtocolError::DecodeError(e.to_string()))?;
+
+        let decoded = if self.config.url_safe {
+            base64::Engine::decode(&base64::engine::general_purpose::URL_SAFE_NO_PAD, &data_str)
+        } else if self.config.padding {
+            base64::Engine::decode(&base64::engine::general_purpose::STANDARD, &data_str)
+        } else {
+            // Try standard first, then URL-safe
+            base64::Engine::decode(&base64::engine::general_purpose::STANDARD, &data_str).or_else(
+                |_| {
+                    base64::Engine::decode(
+                        &base64::engine::general_purpose::URL_SAFE_NO_PAD,
+                        &data_str,
+                    )
+                },
+            )
+        };
+
+        decoded.map_err(|e| ProtocolError::DecodeError(e.to_string()))
+    }
+
+    fn status(&self) -> Value {
+        serde_json::json!({
+            "protocol": "base64",
+            "url_safe": self.config.url_safe,
+            "padding": self.config.padding,
+        })
+    }
+}
+
+/// Identity (pass-through) protocol
+pub struct IdentityProtocol;
+
+impl IdentityProtocol {
+    pub fn new() -> Self {
+        Self
+    }
+}
+
+impl Default for IdentityProtocol {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+impl Protocol for IdentityProtocol {
+    fn name(&self) -> &'static str {
+        "identity"
+    }
+
+    fn encode(&self, data: &[u8]) -> Result<Vec<u8>, ProtocolError> {
+        Ok(data.to_vec())
+    }
+
+    fn decode(&self, data: &[u8]) -> Result<Vec<u8>, ProtocolError> {
+        Ok(data.to_vec())
+    }
+
+    fn status(&self) -> Value {
+        serde_json::json!({
+            "protocol": "identity",
+        })
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_base64_encode() {
+        let proto = Base64Protocol::new(Default::default());
+        let data = b"Hello, World!";
+        let encoded = proto.encode(data).unwrap();
+        let decoded = proto.decode(&encoded).unwrap();
+        assert_eq!(decoded, data);
+    }
+
+    #[test]
+    fn test_base64_url_safe() {
+        let proto = Base64Protocol::new(Base64Config {
+            url_safe: true,
+            padding: false,
+        });
+        let data = b"test+/data";
+        let encoded = proto.encode(data).unwrap();
+        let encoded_str = String::from_utf8(encoded).unwrap();
+        assert!(!encoded_str.contains('+'));
+        assert!(!encoded_str.contains('/'));
+    }
+}

src/tree/protocols/http.rs

@@ -0,0 +1,223 @@
+//! HTTP protocol implementation for tree communication.
+//!
+//! This protocol wraps data in HTTP requests/responses for traffic blending.
+
+use crate::tree::protocols::stack::{HttpConfig, Protocol, ProtocolError};
+use serde_json::Value;
+
+/// HTTP protocol for tree communication.
+///
+/// Wraps outgoing data in HTTP requests and parses incoming HTTP responses.
+pub struct HttpProtocol {
+    config: HttpConfig,
+}
+
+impl HttpProtocol {
+    pub fn new(config: HttpConfig) -> Self {
+        Self { config }
+    }
+
+    /// Build HTTP request
+    fn build_request(&self, body: &[u8]) -> Vec<u8> {
+        let body_len = body.len();
+        let body_str = String::from_utf8_lossy(body);
+
+        let mut request = format!(
+            "{} {} HTTP/1.1\r\n\
+             Host: {}\r\n\
+             User-Agent: {}\r\n\
+             Content-Type: application/json\r\n\
+             Content-Length: {}\r\n",
+            self.config.method,
+            self.config.path,
+            "localhost", // Would be configured in production
+            self.config.user_agent,
+            body_len
+        );
+
+        // Add custom headers
+        for (key, value) in &self.config.headers {
+            request.push_str(&format!("{}: {}\r\n", key, value));
+        }
+
+        request.push_str("\r\n");
+        request.push_str(&body_str);
+
+        request.into_bytes()
+    }
+
+    /// Parse HTTP response and extract body
+    fn parse_response(&self, data: &[u8]) -> Result<Vec<u8>, ProtocolError> {
+        let data_str = String::from_utf8(data.to_vec())
+            .map_err(|e| ProtocolError::DecodeError(e.to_string()))?;
+
+        // Find body start (after \r\n\r\n)
+        let body_start = match data_str.find("\r\n\r\n") {
+            Some(pos) => pos + 4,
+            None => {
+                return Err(ProtocolError::DecodeError(
+                    "Invalid HTTP response".to_string(),
+                ))
+            }
+        };
+
+        // Extract status code
+        let status_line = data_str
+            .split("\r\n")
+            .next()
+            .ok_or_else(|| ProtocolError::DecodeError("No status line".to_string()))?;
+
+        let status_code: u16 = status_line
+            .split_whitespace()
+            .nth(1)
+            .and_then(|s| s.parse().ok())
+            .ok_or_else(|| ProtocolError::DecodeError("Invalid status code".to_string()))?;
+
+        if status_code < 200 || status_code >= 300 {
+            return Err(ProtocolError::DecodeError(format!(
+                "HTTP error: {}",
+                status_code
+            )));
+        }
+
+        // Extract body
+        let body = &data_str[body_start..];
+        Ok(body.as_bytes().to_vec())
+    }
+}
+
+impl Protocol for HttpProtocol {
+    fn name(&self) -> &'static str {
+        "http"
+    }
+
+    fn encode(&self, data: &[u8]) -> Result<Vec<u8>, ProtocolError> {
+        Ok(self.build_request(data))
+    }
+
+    fn decode(&self, data: &[u8]) -> Result<Vec<u8>, ProtocolError> {
+        self.parse_response(data)
+    }
+
+    fn status(&self) -> Value {
+        serde_json::json!({
+            "protocol": "http",
+            "method": self.config.method,
+            "path": self.config.path,
+            "headers": self.config.headers,
+            "user_agent": self.config.user_agent,
+        })
+    }
+}
+
+/// HTTP server for receiving tree messages.
+///
+/// This is a simple implementation for testing - in production you'd
+/// use a proper HTTP server.
+pub struct HttpServer {
+    config: HttpConfig,
+}
+
+impl HttpServer {
+    pub fn new(config: HttpConfig) -> Self {
+        Self { config }
+    }
+
+    /// Parse incoming HTTP request and extract body
+    pub fn parse_request(&self, data: &[u8]) -> Result<Vec<u8>, ProtocolError> {
+        let data_str = String::from_utf8(data.to_vec())
+            .map_err(|e| ProtocolError::DecodeError(e.to_string()))?;
+
+        // Find body start
+        let body_start = match data_str.find("\r\n\r\n") {
+            Some(pos) => pos + 4,
+            None => {
+                return Err(ProtocolError::DecodeError(
+                    "Invalid HTTP request".to_string(),
+                ))
+            }
+        };
+
+        // Extract Content-Length
+        let mut content_length = 0;
+        for line in data_str.lines() {
+            if line.to_lowercase().starts_with("content-length:") {
+                content_length = line
+                    .split(':')
+                    .nth(1)
+                    .and_then(|s| s.trim().parse().ok())
+                    .unwrap_or(0);
+                break;
+            }
+        }
+
+        let body = &data_str[body_start..];
+        if body.len() >= content_length {
+            Ok(body[..content_length].as_bytes().to_vec())
+        } else {
+            Ok(body.as_bytes().to_vec())
+        }
+    }
+
+    /// Build HTTP response
+    pub fn build_response(&self, body: &[u8], status: u16) -> Vec<u8> {
+        let body_len = body.len();
+        let body_str = String::from_utf8_lossy(body);
+
+        let status_text = match status {
+            200 => "OK",
+            400 => "Bad Request",
+            404 => "Not Found",
+            500 => "Internal Server Error",
+            _ => "Unknown",
+        };
+
+        format!(
+            "HTTP/1.1 {} {}\r\n\
+             Content-Type: application/json\r\n\
+             Content-Length: {}\r\n\
+             Connection: close\r\n\
+             \r\n\
+             {}",
+            status, status_text, body_len, body_str
+        )
+        .into_bytes()
+    }
+}
+
+impl Default for HttpServer {
+    fn default() -> Self {
+        Self::new(Default::default())
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_http_encode_decode() {
+        let proto = HttpProtocol::new(Default::default());
+
+        let data = r#"{"action": "test", "data": "hello"}"#.as_bytes();
+        let encoded = proto.encode(data).unwrap();
+
+        // Build a valid response
+        let response = b"HTTP/1.1 200 OK\r\nContent-Length: 29\r\n\r\n{\"action\": \"test\", \"data\": \"hello\"}";
+
+        let decoded = proto.decode(response).unwrap();
+        assert_eq!(decoded, data);
+    }
+
+    #[test]
+    fn test_request_building() {
+        let server = HttpServer::new(Default::default());
+
+        let body = r#"{"test": "data"}"#.as_bytes();
+        let request = server.build_request(body);
+
+        let request_str = String::from_utf8(request).unwrap();
+        assert!(request_str.contains("POST / HTTP/1.1"));
+        assert!(request_str.contains("Content-Length: 16"));
+    }
+}

src/tree/protocols/mod.rs

@@ -0,0 +1,42 @@
+//! Protocol stacking system for extensible network communication.
+//!
+//! This module provides a way to layer multiple protocols on top of each other,
+//! similar to a network stack. Each protocol can encode/decode data from the layer below.
+//!
+//! # Architecture
+//!
+//! Each protocol implements the `Protocol` trait, defining:
+//! - How to encode data going "out" (to the network)
+//! - How to decode data coming "in" (from the network)
+//! - Configuration for the protocol
+//!
+//! # Usage
+//!
+//! ```rust
+//! use tree::protocols::{Protocol, ProtocolStack, ProtocolConfig};
+//! use serde_json::json;
+//!
+//! // Create a stack: base64 -> http -> tcp
+//! let stack: ProtocolStack = vec![
+//!     ProtocolConfig::Base64(json!({})),
+//!     ProtocolConfig::Http(json!({
+//!         "method": "POST",
+//!         "path": "/api/data"
+//!     })),
+//! ];
+//!
+//! // Encode outgoing message
+//! let encoded = stack.encode(&json!({"action": "test"}))?;
+//!
+//! // Decode incoming data
+//! let decoded = stack.decode(&encoded)?;
+//! ```
+
+pub mod base64;
+pub mod http;
+pub mod stack;
+
+pub use stack::{
+    Base64Config, HttpConfig, Protocol, ProtocolConfig, ProtocolError, ProtocolStack, TcpConfig,
+    WebSocketConfig,
+};

src/tree/protocols/stack.rs

@@ -0,0 +1,503 @@
+//! Protocol stack implementation for layered network communication.
+//!
+//! The stack processes protocols from outermost (closest to app) to innermost (closest to network).
+
+use serde::{Deserialize, Serialize};
+use serde_json::Value;
+use thiserror::Error;
+
+use crate::tree::message::TreeMessage;
+
+#[derive(Error, Debug)]
+pub enum ProtocolError {
+    #[error("Encoding failed: {0}")]
+    EncodeError(String),
+    #[error("Decoding failed: {0}")]
+    DecodeError(String),
+    #[error("Invalid configuration: {0}")]
+    ConfigError(String),
+    #[error("Protocol not found: {0}")]
+    NotFound(String),
+}
+
+/// Core trait for protocol implementations.
+///
+/// Each protocol can:
+/// - Encode: Transform data going outward (app -> network)
+/// - Decode: Transform data coming inward (network -> app)
+pub trait Protocol: Send + Sync {
+    /// Unique name for this protocol
+    fn name(&self) -> &'static str;
+
+    /// Encode data going outward (toward network)
+    fn encode(&self, data: &[u8]) -> Result<Vec<u8>, ProtocolError>;
+
+    /// Decode data coming inward (from network)
+    fn decode(&self, data: &[u8]) -> Result<Vec<u8>, ProtocolError>;
+
+    /// Get protocol status/info
+    fn status(&self) -> Value;
+}
+
+/// Configuration for a single protocol layer.
+///
+/// This allows protocols to be configured dynamically via JSON.
+#[derive(Debug, Clone, Serialize, Deserialize)]
+#[serde(tag = "protocol", rename_all = "snake_case")]
+pub enum ProtocolConfig {
+    /// No-op pass-through protocol
+    Identity,
+    /// Base64 encoding
+    Base64(Base64Config),
+    /// HTTP protocol
+    Http(HttpConfig),
+    /// TCP raw protocol
+    Tcp(TcpConfig),
+    /// WebSocket protocol
+    WebSocket(WebSocketConfig),
+    /// Custom protocol (for future extensions)
+    Custom { name: String, config: Value },
+}
+
+/// Base64 encoding configuration
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct Base64Config {
+    /// Use URL-safe base64 variant
+    #[serde(default)]
+    pub url_safe: bool,
+    /// Add padding
+    #[serde(default = "default_true")]
+    pub padding: bool,
+}
+
+fn default_true() -> bool {
+    true
+}
+
+impl Default for Base64Config {
+    fn default() -> Self {
+        Self {
+            url_safe: false,
+            padding: true,
+        }
+    }
+}
+
+/// HTTP protocol configuration
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct HttpConfig {
+    /// HTTP method
+    #[serde(default = "default_post")]
+    pub method: String,
+    /// Request path
+    #[serde(default)]
+    pub path: String,
+    /// Headers to add
+    #[serde(default)]
+    pub headers: std::collections::HashMap<String, String>,
+    /// User agent
+    #[serde(default)]
+    pub user_agent: String,
+}
+
+fn default_post() -> String {
+    "POST".to_string()
+}
+
+impl Default for HttpConfig {
+    fn default() -> Self {
+        Self {
+            method: "POST".to_string(),
+            path: "/".to_string(),
+            headers: std::collections::HashMap::new(),
+            user_agent: "TreeProtocol/1.0".to_string(),
+        }
+    }
+}
+
+/// TCP raw protocol configuration  
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct TcpConfig {
+    /// Delimiter for message framing
+    #[serde(default)]
+    pub delimiter: String,
+    /// Include length prefix
+    #[serde(default)]
+    pub length_prefix: bool,
+}
+
+impl Default for TcpConfig {
+    fn default() -> Self {
+        Self {
+            delimiter: "\n".to_string(),
+            length_prefix: false,
+        }
+    }
+}
+
+/// WebSocket configuration
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct WebSocketConfig {
+    /// WebSocket subprotocol
+    #[serde(default)]
+    pub subprotocol: Option<String>,
+    /// Path for WS connection
+    #[serde(default)]
+    pub path: String,
+}
+
+impl Default for WebSocketConfig {
+    fn default() -> Self {
+        Self {
+            subprotocol: None,
+            path: "/".to_string(),
+        }
+    }
+}
+
+/// A stack of protocols to process data through.
+///
+/// Data flows through the stack:
+/// - Encoding: App -> Protocol N -> ... -> Protocol 1 -> Network
+/// - Decoding: Network -> Protocol 1 -> ... -> Protocol N -> App
+pub struct ProtocolStack {
+    /// Stack of protocols (outermost first for encoding)
+    protocols: Vec<Box<dyn Protocol>>,
+    /// Configuration order (for serialization)
+    config_order: Vec<String>,
+}
+
+impl Clone for ProtocolStack {
+    fn clone(&self) -> Self {
+        Self {
+            protocols: Vec::new(), // Can't clone protocols
+            config_order: self.config_order.clone(),
+        }
+    }
+}
+
+impl std::fmt::Debug for ProtocolStack {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        f.debug_struct("ProtocolStack")
+            .field("config_order", &self.config_order)
+            .field("protocols", &self.protocols.len())
+            .finish()
+    }
+}
+
+impl ProtocolStack {
+    /// Create a new empty stack
+    pub fn new() -> Self {
+        Self {
+            protocols: Vec::new(),
+            config_order: Vec::new(),
+        }
+    }
+
+    /// Create a stack from configurations
+    pub fn from_configs(configs: &[ProtocolConfig]) -> Result<Self, ProtocolError> {
+        let mut stack = Self::new();
+        for config in configs {
+            stack.push(config)?;
+        }
+        Ok(stack)
+    }
+
+    /// Add a protocol to the stack (outermost position)
+    pub fn push(&mut self, config: &ProtocolConfig) -> Result<(), ProtocolError> {
+        let (protocol, name) = match config {
+            ProtocolConfig::Identity => {
+                let p = crate::tree::protocols::base64::IdentityProtocol::new();
+                (Box::new(p) as Box<dyn Protocol>, "identity".to_string())
+            }
+            ProtocolConfig::Base64(cfg) => {
+                let p = crate::tree::protocols::base64::Base64Protocol::new(cfg.clone());
+                (Box::new(p) as Box<dyn Protocol>, "base64".to_string())
+            }
+            ProtocolConfig::Http(cfg) => {
+                let p = crate::tree::protocols::http::HttpProtocol::new(cfg.clone());
+                (Box::new(p) as Box<dyn Protocol>, "http".to_string())
+            }
+            ProtocolConfig::Tcp(cfg) => {
+                let p = TcpProtocol::new(cfg.clone());
+                (Box::new(p) as Box<dyn Protocol>, "tcp".to_string())
+            }
+            ProtocolConfig::WebSocket(cfg) => {
+                let p = WebSocketProtocol::new(cfg.clone());
+                (Box::new(p) as Box<dyn Protocol>, "websocket".to_string())
+            }
+            ProtocolConfig::Custom { name, config } => {
+                return Err(ProtocolError::NotFound(format!(
+                    "Custom protocol '{}' not implemented",
+                    name
+                )));
+            }
+        };
+
+        self.config_order.push(name);
+        self.protocols.push(protocol);
+        Ok(())
+    }
+
+    /// Remove the outermost protocol
+    pub fn pop(&mut self) -> Option<Box<dyn Protocol>> {
+        self.config_order.pop()?;
+        self.protocols.pop()
+    }
+
+    /// Get number of protocols in stack
+    pub fn len(&self) -> usize {
+        self.protocols.len()
+    }
+
+    /// Check if stack is empty
+    pub fn is_empty(&self) -> bool {
+        self.protocols.is_empty()
+    }
+
+    /// Encode data through the entire stack (app -> network)
+    pub fn encode(&self, data: &[u8]) -> Result<Vec<u8>, ProtocolError> {
+        let mut result = data.to_vec();
+        for protocol in self.protocols.iter() {
+            result = protocol.encode(&result)?;
+        }
+        Ok(result)
+    }
+
+    /// Decode data through the entire stack (network -> app)
+    pub fn decode(&self, data: &[u8]) -> Result<Vec<u8>, ProtocolError> {
+        let mut result = data.to_vec();
+        // Decode in reverse order (innermost to outermost)
+        for protocol in self.protocols.iter().rev() {
+            result = protocol.decode(&result)?;
+        }
+        Ok(result)
+    }
+
+    /// Encode a TreeMessage through the stack
+    pub fn encode_message(&self, message: &TreeMessage) -> Result<Vec<u8>, ProtocolError> {
+        let json =
+            serde_json::to_vec(message).map_err(|e| ProtocolError::EncodeError(e.to_string()))?;
+        self.encode(&json)
+    }
+
+    /// Decode data into a TreeMessage
+    pub fn decode_message(&self, data: &[u8]) -> Result<TreeMessage, ProtocolError> {
+        let decoded = self.decode(data)?;
+        serde_json::from_slice(&decoded).map_err(|e| ProtocolError::DecodeError(e.to_string()))
+    }
+
+    /// Get status of all protocols in stack
+    pub fn status(&self) -> Vec<Value> {
+        self.protocols.iter().map(|p| p.status()).collect()
+    }
+
+    /// Get the configuration for serialization
+    pub fn to_configs(&self) -> Vec<ProtocolConfig> {
+        self.config_order
+            .iter()
+            .enumerate()
+            .filter_map(|(_, name)| {
+                // This is simplified - in production you'd store configs
+                Some(match name.as_str() {
+                    "identity" => ProtocolConfig::Identity,
+                    "base64" => ProtocolConfig::Base64(Default::default()),
+                    "http" => ProtocolConfig::Http(Default::default()),
+                    "tcp" => ProtocolConfig::Tcp(Default::default()),
+                    "websocket" => ProtocolConfig::WebSocket(Default::default()),
+                    _ => return None,
+                })
+            })
+            .collect()
+    }
+}
+
+impl Default for ProtocolStack {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+/// TCP protocol implementation (simple framing)
+pub struct TcpProtocol {
+    config: TcpConfig,
+}
+
+impl TcpProtocol {
+    pub fn new(config: TcpConfig) -> Self {
+        Self { config }
+    }
+}
+
+impl Protocol for TcpProtocol {
+    fn name(&self) -> &'static str {
+        "tcp"
+    }
+
+    fn encode(&self, data: &[u8]) -> Result<Vec<u8>, ProtocolError> {
+        let mut result = Vec::new();
+
+        if self.config.length_prefix {
+            let len = (data.len() as u32).to_be_bytes();
+            result.extend_from_slice(&len);
+        }
+
+        result.extend_from_slice(data);
+
+        if !self.config.length_prefix && !self.config.delimiter.is_empty() {
+            result.extend_from_slice(self.config.delimiter.as_bytes());
+        }
+
+        Ok(result)
+    }
+
+    fn decode(&self, data: &[u8]) -> Result<Vec<u8>, ProtocolError> {
+        let mut result = data.to_vec();
+
+        // Remove delimiter if present
+        if !self.config.delimiter.is_empty() {
+            if let Some(pos) = result
+                .iter()
+                .position(|&b| self.config.delimiter.as_bytes().contains(&b))
+            {
+                result.truncate(pos);
+            }
+        }
+
+        // If length prefix, skip it
+        if self.config.length_prefix && result.len() >= 4 {
+            let len = u32::from_be_bytes([result[0], result[1], result[2], result[3]]) as usize;
+            if result.len() >= 4 + len {
+                result = result[4..4 + len].to_vec();
+            }
+        }
+
+        Ok(result)
+    }
+
+    fn status(&self) -> Value {
+        serde_json::json!({
+            "protocol": "tcp",
+            "delimiter": self.config.delimiter,
+            "length_prefix": self.config.length_prefix,
+        })
+    }
+}
+
+/// WebSocket protocol implementation (simplified)
+pub struct WebSocketProtocol {
+    config: WebSocketConfig,
+}
+
+impl WebSocketProtocol {
+    pub fn new(config: WebSocketConfig) -> Self {
+        Self { config }
+    }
+}
+
+impl Protocol for WebSocketProtocol {
+    fn name(&self) -> &'static str {
+        "websocket"
+    }
+
+    fn encode(&self, data: &[u8]) -> Result<Vec<u8>, ProtocolError> {
+        // Simple WebSocket text frame: FIN(1) + opcode(1) + length(2) + data
+        let mut frame = vec![0x81]; // FIN + text opcode
+        let len = data.len();
+        if len < 126 {
+            frame.push(len as u8);
+        } else if len < 65536 {
+            frame.push(126);
+            frame.extend_from_slice(&(len as u16).to_be_bytes());
+        } else {
+            frame.push(127);
+            frame.extend_from_slice(&(len as u64).to_be_bytes());
+        }
+        frame.extend_from_slice(data);
+        Ok(frame)
+    }
+
+    fn decode(&self, data: &[u8]) -> Result<Vec<u8>, ProtocolError> {
+        if data.len() < 2 {
+            return Err(ProtocolError::DecodeError("Frame too short".to_string()));
+        }
+
+        let opcode = data[0] & 0x0f;
+        if opcode == 0x08 {
+            // Close frame
+            return Err(ProtocolError::DecodeError("Connection closed".to_string()));
+        }
+
+        let len = data[1] & 0x7f;
+        let header_len = match len {
+            126 => 4,
+            127 => 10,
+            _ => 2,
+        };
+
+        if data.len() > header_len {
+            Ok(data[header_len..].to_vec())
+        } else {
+            Err(ProtocolError::DecodeError("Incomplete frame".to_string()))
+        }
+    }
+
+    fn status(&self) -> Value {
+        serde_json::json!({
+            "protocol": "websocket",
+            "path": self.config.path,
+            "subprotocol": self.config.subprotocol,
+        })
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_base64_stack() {
+        let mut stack = ProtocolStack::new();
+        stack
+            .push(&ProtocolConfig::Base64(Default::default()))
+            .unwrap();
+
+        let data = b"hello world";
+        let encoded = stack.encode(data).unwrap();
+        let decoded = stack.decode(&encoded).unwrap();
+
+        assert_eq!(decoded, data);
+    }
+
+    #[test]
+    fn test_multi_layer_stack() {
+        let mut stack = ProtocolStack::new();
+        stack
+            .push(&ProtocolConfig::Base64(Default::default()))
+            .unwrap();
+        stack
+            .push(&ProtocolConfig::Tcp(Default::default()))
+            .unwrap();
+
+        let data = b"test message";
+        let encoded = stack.encode(data).unwrap();
+        let decoded = stack.decode(&encoded).unwrap();
+
+        assert_eq!(decoded, data);
+    }
+
+    #[test]
+    fn test_http_config() {
+        let config = HttpConfig {
+            method: "POST".to_string(),
+            path: "/api/test".to_string(),
+            headers: std::collections::HashMap::new(),
+            user_agent: "Test/1.0".to_string(),
+        };
+
+        let mut stack = ProtocolStack::new();
+        stack.push(&ProtocolConfig::Http(config)).unwrap();
+
+        assert_eq!(stack.len(), 1);
+    }
+}

src/tree/tcp/client.rs

@@ -1,47 +1,85 @@
 //! TCP Client component for outbound connections.
 //!
 //! Provides a TreeElement for managing TCP client connections with
-//! configuration, status queries, and reconnection support.
+//! configuration, status queries, reconnection support, and protocol stacking.
 
 use std::io::{Read, Write};
 use std::net::TcpStream;
 use std::sync::{Arc, Mutex};
 use std::time::Duration;
 
+use serde::{Deserialize, Serialize};
 use serde_json::{json, Value};
 
 use crate::tree::component::Component;
+use crate::tree::message::TreeMessage;
+use crate::tree::protocols::{ProtocolConfig, ProtocolStack};
 use crate::tree::symbols;
 use crate::tree::tcp::config::{ConnectionStatus, TcpClientConfig};
 use crate::tree::{Branch, TreeElement};
 
-/// TCP Client component
+/// TCP Client component with protocol stacking support.
+///
+/// This component can:
+/// - Connect to remote TCP servers
+/// - Apply protocol stacks (base64, http, etc.)
+/// - Send/receive messages via RPC
+/// - Auto-reconnect on failure
+#[derive(Debug, Serialize, Deserialize)]
 pub struct TcpClient {
-    name: String,
+    /// Unique name for this client
-    config: TcpClientConfig,
+    pub name: String,
+    /// Connection configuration
+    pub config: TcpClientConfig,
+    /// Protocol stack configuration
+    #[serde(default)]
+    pub protocols: Vec<ProtocolConfig>,
+    /// Current connection status
+    #[serde(skip)]
     status: ConnectionStatus,
+    /// Active TCP stream
+    #[serde(skip)]
     stream: Option<Arc<Mutex<TcpStream>>>,
+    /// Protocol stack (runtime)
+    #[serde(skip)]
+    protocol_stack: ProtocolStack,
+    /// Internal tree structure
+    #[serde(skip)]
     branch: Branch,
 }
 
 impl TcpClient {
+    /// Create a new TCP client with default settings
     pub fn new(name: impl Into<String>) -> Self {
-        let name = name.into();
+        Self::with_config(name, TcpClientConfig::default())
-        let mut branch = Branch::new("TCPClient");
+    }
 
-        // Add internal state branch
+    /// Create a new TCP client with custom configuration
+    pub fn with_config(name: impl Into<String>, config: TcpClientConfig) -> Self {
+        let name = name.into();
+
+        let mut branch = Branch::new("TCPClient");
         let state_branch = Branch::new("state");
         branch.add_child("state", Box::new(state_branch));
 
         Self {
             name: name.clone(),
-            config: TcpClientConfig::default(),
+            config,
+            protocols: Vec::new(),
             status: ConnectionStatus::disconnected(),
             stream: None,
+            protocol_stack: ProtocolStack::new(),
             branch,
         }
     }
 
+    /// Set protocol stack configuration
+    pub fn set_protocols(&mut self, protocols: Vec<ProtocolConfig>) -> Result<(), String> {
+        self.protocols = protocols.clone();
+        self.protocol_stack = ProtocolStack::from_configs(&protocols).map_err(|e| e.to_string())?;
+        Ok(())
+    }
+
     /// Connect to the configured address
     pub fn connect(&mut self) -> Result<(), String> {
         let addr = format!("{}:{}", self.config.address, self.config.port);
@@ -85,32 +123,66 @@ impl TcpClient {
         self.status.connected
     }
 
-    /// Send data over the connection
+    /// Send raw data over the connection
-    pub fn send(&mut self, data: &[u8]) -> Result<usize, String> {
+    pub fn send_raw(&mut self, data: &[u8]) -> Result<usize, String> {
         let stream = self.stream.as_ref().ok_or("Not connected")?;
-
         let mut stream = stream.lock().map_err(|e| format!("Lock failed: {}", e))?;
-
         stream
             .write(data)
             .map_err(|e| format!("Write failed: {}", e))
     }
 
-    /// Receive data from the connection
+    /// Receive raw data from the connection
-    pub fn recv(&mut self, buffer_size: usize) -> Result<Vec<u8>, String> {
+    pub fn recv_raw(&mut self, buffer_size: usize) -> Result<Vec<u8>, String> {
         let stream = self.stream.as_ref().ok_or("Not connected")?;
-
         let mut stream = stream.lock().map_err(|e| format!("Lock failed: {}", e))?;
-
         let mut buffer = vec![0u8; buffer_size];
         let n = stream
             .read(&mut buffer)
             .map_err(|e| format!("Read failed: {}", e))?;
-
         buffer.truncate(n);
         Ok(buffer)
     }
 
+    /// Send a TreeMessage through the protocol stack
+    pub fn send_message_raw(&mut self, message: &TreeMessage) -> Result<(), String> {
+        let encoded = self
+            .protocol_stack
+            .encode_message(message)
+            .map_err(|e| format!("Encoding failed: {}", e))?;
+
+        self.send_raw(&encoded)?;
+        Ok(())
+    }
+
+    /// Receive and decode a TreeMessage
+    pub fn recv_message(&mut self, buffer_size: usize) -> Result<TreeMessage, String> {
+        let data = self.recv_raw(buffer_size)?;
+
+        self.protocol_stack
+            .decode_message(&data)
+            .map_err(|e| format!("Decoding failed: {}", e))
+    }
+
+    /// Send and wait for response (RPC pattern)
+    pub fn rpc_call(&mut self, message: &TreeMessage) -> Result<TreeMessage, String> {
+        let id = message.id.clone();
+
+        self.send_message_raw(message)?;
+
+        // Simple blocking receive - in production would have timeout
+        let response = self.recv_message(4096)?;
+
+        // Verify it's a response to our message
+        if let Some(response_to) = &response.response_to {
+            if response_to != id.as_deref().unwrap_or("") {
+                return Err("Response ID mismatch".to_string());
+            }
+        }
+
+        Ok(response)
+    }
+
     /// Get current configuration
     pub fn config(&self) -> &TcpClientConfig {
         &self.config
@@ -127,12 +199,87 @@ impl TcpClient {
             "connected": self.status.connected,
             "remote_address": self.status.remote_address,
             "local_address": self.status.local_address,
-            "config": {
+            "bytes_sent": self.status.bytes_sent,
-                "address": self.config.address,
+            "bytes_received": self.status.bytes_received,
-                "port": self.config.port,
+            "config": self.config,
-            }
+            "protocols": self.protocol_stack.to_configs(),
         })
     }
+
+    /// Handle RPC call from message
+    fn handle_rpc(&mut self, payload: &Value) -> Value {
+        let method = match payload.get("method").and_then(|m| m.as_str()) {
+            Some(m) => m,
+            None => return json!({"success": false, "error": "missing method"}),
+        };
+
+        let params = payload.get("params").cloned().unwrap_or(Value::Null);
+
+        match method {
+            "connect" => {
+                // Allow override of address/port
+                if let Some(addr) = params.get("address").and_then(|a| a.as_str()) {
+                    self.config.address = addr.to_string();
+                }
+                if let Some(port) = params.get("port").and_then(|p| p.as_u64()) {
+                    self.config.port = port as u16;
+                }
+
+                match self.connect() {
+                    Ok(_) => json!({"success": true, "status": self.status}),
+                    Err(e) => json!({"success": false, "error": e}),
+                }
+            }
+            "disconnect" => match self.disconnect() {
+                Ok(_) => json!({"success": true}),
+                Err(e) => json!({"success": false, "error": e}),
+            },
+            "send" => {
+                let data = params
+                    .get("data")
+                    .and_then(|d| d.as_str())
+                    .map(|s| s.as_bytes().to_vec());
+
+                match data {
+                    Some(data) => match self.send_raw(&data) {
+                        Ok(n) => json!({"success": true, "bytes_sent": n}),
+                        Err(e) => json!({"success": false, "error": e}),
+                    },
+                    None => json!({"success": false, "error": "missing data"}),
+                }
+            }
+            "recv" => {
+                let size = params
+                    .get("size")
+                    .and_then(|s| s.as_u64())
+                    .map(|s| s as usize)
+                    .unwrap_or(4096);
+                match self.recv_raw(size) {
+                    Ok(data) => json!({
+                        "success": true,
+                        "data": String::from_utf8_lossy(&data),
+                        "bytes": data.len()
+                    }),
+                    Err(e) => json!({"success": false, "error": e}),
+                }
+            }
+            "status" => self.get_status(),
+            "set_protocols" => {
+                if let Some(protocols) = params.get("protocols") {
+                    match serde_json::from_value(protocols.clone()) {
+                        Ok(p) => match self.set_protocols(p) {
+                            Ok(_) => json!({"success": true}),
+                            Err(e) => json!({"success": false, "error": e}),
+                        },
+                        Err(e) => json!({"success": false, "error": e.to_string()}),
+                    }
+                } else {
+                    json!({"success": false, "error": "missing protocols"})
+                }
+            }
+            _ => json!({"success": false, "error": format!("unknown method: {}", method)}),
+        }
+    }
 }
 
 impl Component for TcpClient {
@@ -145,8 +292,21 @@ impl Component for TcpClient {
     }
 
     fn init(&mut self, config: Value) -> Result<(), String> {
-        self.config =
+        // Support both legacy config and new format
-            serde_json::from_value(config).map_err(|e| format!("Invalid config: {}", e))?;
+        if let Some(client_config) = config.get("config") {
+            self.config = serde_json::from_value(client_config.clone())
+                .map_err(|e| format!("Invalid config: {}", e))?;
+        } else {
+            self.config = serde_json::from_value(config.clone())
+                .map_err(|e| format!("Invalid config: {}", e))?;
+        }
+
+        if let Some(protocols) = config.get("protocols") {
+            let p: Vec<ProtocolConfig> = serde_json::from_value(protocols.clone())
+                .map_err(|e| format!("Invalid protocols: {}", e))?;
+            self.set_protocols(p)?;
+        }
+
         self.connect()?;
         Ok(())
     }
@@ -158,12 +318,21 @@ impl Component for TcpClient {
 
 impl TreeElement for TcpClient {
     fn get_type(&self) -> Value {
-        json!("TCPClient")
+        json!({
+            "type": "TCPClient",
+            "name": self.name,
+        })
     }
 
     fn send_message(&mut self, target: Value, message: Value) -> Value {
         match target {
             Value::Null => {
+                // Check for RPC call format
+                if message.get("method").is_some() {
+                    return self.handle_rpc(&message);
+                }
+
+                // Legacy string commands
                 if let Some(cmd) = message.as_str() {
                     match cmd {
                         "Connect" => match self.connect() {
@@ -196,6 +365,9 @@ impl TreeElement for TcpClient {
                             }
                             Err(e) => json!({"success": false, "error": e.to_string()}),
                         }
+                    } else if obj.get("method").is_some() {
+                        let payload = Value::Object(obj.clone());
+                        self.handle_rpc(&payload)
                     } else {
                         json!(symbols::ERR_INVALID_COMMAND)
                     }
@@ -203,23 +375,45 @@ impl TreeElement for TcpClient {
                     json!(symbols::ERR_INVALID_COMMAND)
                 }
             }
-            Value::String(subtarget) => {
+            Value::String(subtarget) => match subtarget.as_str() {
-                match subtarget.as_str() {
+                "config" => json!(self.config),
-                    "config" => {
+                "state" => json!({
-                        // Return or modify configuration
+                    "connected": self.status.connected,
-                        json!(self.config)
+                    "remote": self.status.remote_address,
-                    }
+                }),
-                    "state" => {
+                "protocols" => json!(self.protocol_stack.to_configs()),
-                        // Return connection state
+                _ => json!(symbols::ERR_CHILD_NOT_FOUND),
-                        json!({
+            },
-                            "connected": self.status.connected,
-                            "remote": self.status.remote_address,
-                        })
-                    }
-                    _ => json!(symbols::ERR_CHILD_NOT_FOUND),
-                }
-            }
             _ => json!(symbols::ERR_INVALID_TARGET),
         }
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_client_creation() {
+        let client = TcpClient::new("test-client");
+        assert_eq!(client.name(), "test-client");
+        assert!(!client.is_connected());
+    }
+
+    #[test]
+    fn test_config_serialization() {
+        let client = TcpClient::with_config("test", TcpClientConfig::new("127.0.0.1", 8080));
+        let json = serde_json::to_string(&client).unwrap();
+        assert!(json.contains("test"));
+        assert!(json.contains("127.0.0.1"));
+    }
+
+    #[test]
+    fn test_rpc_status() {
+        let mut client = TcpClient::new("test");
+        let result = client.send_message(json!(null), json!({"method": "status"}));
+
+        let obj = result.as_object().unwrap();
+        assert!(obj.contains_key("connected"));
+    }
+}

src/tree/tcp/config.rs

@@ -98,7 +98,7 @@ impl TcpServerConfig {
 }
 
 /// Connection status information
-#[derive(Debug, Clone, Serialize, Deserialize)]
+#[derive(Debug, Clone, Serialize, Deserialize, Default)]
 pub struct ConnectionStatus {
     pub connected: bool,
     pub remote_address: Option<String>,
@@ -138,7 +138,7 @@ impl ConnectionStatus {
 }
 
 /// Server listener status
-#[derive(Debug, Clone, Serialize, Deserialize)]
+#[derive(Debug, Clone, Serialize, Deserialize, Default)]
 pub struct ListenerStatus {
     pub listening: bool,
     pub bind_address: String,

src/tree/tcp/server.rs

@@ -1,7 +1,7 @@
 //! TCP Server component for inbound connections.
 //!
 //! Provides a TreeElement for managing TCP server listeners with
-//! configuration, status queries, and connection management.
+//! configuration, status queries, connection management, and protocol stacking.
 
 use std::collections::HashMap;
 use std::io::{Read, Write};
@@ -9,41 +9,52 @@ use std::net::{TcpListener, TcpStream};
 use std::sync::{Arc, Mutex};
 use std::time::Duration;
 
+use serde::{Deserialize, Serialize};
 use serde_json::{json, Value};
 
 use crate::tree::component::Component;
+use crate::tree::message::TreeMessage;
+use crate::tree::protocols::{ProtocolConfig, ProtocolStack};
 use crate::tree::symbols;
 use crate::tree::tcp::config::{ListenerStatus, TcpServerConfig};
 use crate::tree::{Branch, TreeElement};
 
 /// A connected client managed by the server
-struct ManagedClient {
+#[derive(Debug)]
-    id: String,
+pub struct ManagedClient {
+    pub id: String,
     stream: TcpStream,
     peer_addr: String,
+    local_addr: String,
 }
 
 impl ManagedClient {
-    fn new(id: String, stream: TcpStream) -> Self {
+    pub fn new(id: String, stream: TcpStream) -> Self {
         let peer_addr = stream
             .peer_addr()
             .map(|a| a.to_string())
             .unwrap_or_else(|_| "unknown".to_string());
 
+        let local_addr = stream
+            .local_addr()
+            .map(|a| a.to_string())
+            .unwrap_or_else(|_| "unknown".to_string());
+
         Self {
             id,
             stream,
             peer_addr,
+            local_addr,
         }
     }
 
-    fn send(&mut self, data: &[u8]) -> Result<usize, String> {
+    pub fn send(&mut self, data: &[u8]) -> Result<usize, String> {
         self.stream
             .write(data)
             .map_err(|e| format!("Write failed: {}", e))
     }
 
-    fn recv(&mut self, buffer_size: usize) -> Result<Vec<u8>, String> {
+    pub fn recv(&mut self, buffer_size: usize) -> Result<Vec<u8>, String> {
         let mut buffer = vec![0u8; buffer_size];
         let _ = self.stream.set_read_timeout(Some(Duration::from_secs(1)));
 
@@ -58,37 +69,86 @@ impl ManagedClient {
         }
     }
 
-    fn peer_address(&self) -> &str {
+    pub fn peer_address(&self) -> &str {
         &self.peer_addr
     }
+
+    pub fn local_address(&self) -> &str {
+        &self.local_addr
+    }
+
+    pub fn set_nonblocking(&mut self, nonblocking: bool) -> Result<(), String> {
+        self.stream
+            .set_nonblocking(nonblocking)
+            .map_err(|e| format!("Failed to set non-blocking: {}", e))
+    }
 }
 
-/// TCP Server component
+/// TCP Server component with protocol stacking support.
+///
+/// This component can:
+/// - Listen for incoming TCP connections
+/// - Manage multiple concurrent connections
+/// - Apply protocol stacks to connections
+/// - Send/receive messages via RPC
+#[derive(Debug, Serialize, Deserialize)]
 pub struct TcpServer {
-    name: String,
+    /// Unique name for this server
-    config: TcpServerConfig,
+    pub name: String,
+    /// Server configuration
+    pub config: TcpServerConfig,
+    /// Protocol stack for incoming connections
+    #[serde(default)]
+    pub protocols: Vec<ProtocolConfig>,
+    /// Current listener status
+    #[serde(skip)]
     status: ListenerStatus,
+    /// TCP listener (runtime only)
+    #[serde(skip)]
     listener: Option<TcpListener>,
+    /// Active clients
+    #[serde(skip)]
     clients: HashMap<String, Arc<Mutex<ManagedClient>>>,
+    /// Protocol stacks per client
+    #[serde(skip)]
+    client_protocols: HashMap<String, ProtocolStack>,
+    /// Total connections since start
     total_connections: u64,
+    /// Internal tree structure
+    #[serde(skip)]
     branch: Branch,
 }
 
 impl TcpServer {
+    /// Create a new TCP server with default settings
     pub fn new(name: impl Into<String>) -> Self {
+        Self::with_config(name, TcpServerConfig::default())
+    }
+
+    /// Create a new TCP server with custom configuration
+    pub fn with_config(name: impl Into<String>, config: TcpServerConfig) -> Self {
         let name = name.into();
 
         Self {
             name: name.clone(),
-            config: TcpServerConfig::default(),
+            config,
+            protocols: Vec::new(),
             status: ListenerStatus::stopped("0.0.0.0", 0),
             listener: None,
             clients: HashMap::new(),
+            client_protocols: HashMap::new(),
             total_connections: 0,
             branch: Branch::new("TCPServer"),
         }
     }
 
+    /// Set protocol stack configuration
+    pub fn set_protocols(&mut self, protocols: Vec<ProtocolConfig>) -> Result<(), String> {
+        self.protocols = protocols.clone();
+        // Don't rebuild client_protocols here - each client gets its own stack
+        Ok(())
+    }
+
     /// Start listening for connections
     pub fn listen(&mut self) -> Result<(), String> {
         let addr = format!("{}:{}", self.config.bind_address, self.config.port);
@@ -114,6 +174,7 @@ impl TcpServer {
     pub fn stop(&mut self) -> Result<(), String> {
         self.listener = None;
         self.clients.clear();
+        self.client_protocols.clear();
         self.status = ListenerStatus::stopped(&self.config.bind_address, self.config.port);
         Ok(())
     }
@@ -135,10 +196,16 @@ impl TcpServer {
     /// Register an accepted connection
     pub fn register_client(&mut self, id: String, stream: TcpStream) {
         let client_id = id.clone();
-        self.clients.insert(
+
-            id,
+        // Create protocol stack for this client
-            Arc::new(Mutex::new(ManagedClient::new(client_id, stream))),
+        let mut protocol_stack = ProtocolStack::new();
-        );
+        for config in &self.protocols {
+            let _ = protocol_stack.push(config);
+        }
+
+        let client = Arc::new(Mutex::new(ManagedClient::new(client_id, stream)));
+        self.clients.insert(id.clone(), client);
+        self.client_protocols.insert(id, protocol_stack);
     }
 
     /// Disconnect a client
@@ -146,6 +213,7 @@ impl TcpServer {
         self.clients
             .remove(id)
             .ok_or_else(|| format!("Client '{}' not found", id))?;
+        self.client_protocols.remove(id);
         Ok(())
     }
 
@@ -157,10 +225,56 @@ impl TcpServer {
             .ok_or_else(|| format!("Client '{}' not found", client_id))?;
 
         let mut client = client.lock().map_err(|e| format!("Lock failed: {}", e))?;
-
         client.send(data)
     }
 
+    /// Receive from a specific client
+    pub fn recv_from(&mut self, client_id: &str, buffer_size: usize) -> Result<Vec<u8>, String> {
+        let client = self
+            .clients
+            .get(client_id)
+            .ok_or_else(|| format!("Client '{}' not found", client_id))?;
+
+        let mut client = client.lock().map_err(|e| format!("Lock failed: {}", e))?;
+        client.recv(buffer_size)
+    }
+
+    /// Send TreeMessage to client through protocol stack
+    pub fn send_message_to(
+        &mut self,
+        client_id: &str,
+        message: &TreeMessage,
+    ) -> Result<(), String> {
+        let protocol_stack = self
+            .client_protocols
+            .get_mut(client_id)
+            .ok_or_else(|| format!("Client '{}' not found", client_id))?;
+
+        let encoded = protocol_stack
+            .encode_message(message)
+            .map_err(|e| format!("Encoding failed: {}", e))?;
+
+        self.send_to(client_id, &encoded).map(|_| ())
+    }
+
+    /// Receive TreeMessage from client through protocol stack
+    pub fn recv_message_from(
+        &mut self,
+        client_id: &str,
+        buffer_size: usize,
+    ) -> Result<TreeMessage, String> {
+        let data = self.recv_from(client_id, buffer_size)?;
+
+        let protocol_stack = self
+            .client_protocols
+            .get_mut(client_id)
+            .ok_or_else(|| format!("Client '{}' not found", client_id))?;
+
+        protocol_stack
+            .decode_message(&data)
+            .map_err(|e| format!("Decoding failed: {}", e))
+    }
+
     /// Check if listening
     pub fn is_listening(&self) -> bool {
         self.status.listening
@@ -178,7 +292,17 @@ impl TcpServer {
 
     /// Get status as JSON
     pub fn get_status(&self) -> Value {
-        let client_list: Vec<Value> = self.clients.keys().map(|k| json!(k)).collect();
+        let client_list: Vec<Value> = self
+            .clients
+            .iter()
+            .map(|(id, client)| {
+                let addr = client
+                    .lock()
+                    .map(|c| c.peer_address().to_string())
+                    .unwrap_or_else(|_| "unknown".to_string());
+                json!({"id": id, "peer": addr})
+            })
+            .collect();
 
         json!({
             "listening": self.status.listening,
@@ -186,9 +310,119 @@ impl TcpServer {
             "port": self.config.port,
             "active_connections": self.clients.len(),
             "total_connections": self.total_connections,
+            "config": self.config,
+            "protocols": self.protocols,
             "clients": client_list,
         })
     }
+
+    /// Handle RPC call from message
+    fn handle_rpc(&mut self, payload: &Value) -> Value {
+        let method = match payload.get("method").and_then(|m| m.as_str()) {
+            Some(m) => m,
+            None => return json!({"success": false, "error": "missing method"}),
+        };
+
+        let params = payload.get("params").cloned().unwrap_or(Value::Null);
+
+        match method {
+            "listen" | "start" => {
+                if let Some(addr) = params.get("bind_address").and_then(|a| a.as_str()) {
+                    self.config.bind_address = addr.to_string();
+                }
+                if let Some(port) = params.get("port").and_then(|p| p.as_u64()) {
+                    self.config.port = port as u16;
+                }
+
+                match self.listen() {
+                    Ok(_) => json!({"success": true, "status": self.status}),
+                    Err(e) => json!({"success": false, "error": e}),
+                }
+            }
+            "stop" => match self.stop() {
+                Ok(_) => json!({"success": true}),
+                Err(e) => json!({"success": false, "error": e}),
+            },
+            "accept" => {
+                // Try to accept a pending connection
+                if let Some((id, stream)) = self.accept() {
+                    self.register_client(id.clone(), stream);
+                    json!({"success": true, "client_id": id})
+                } else {
+                    json!({"success": true, "client_id": null})
+                }
+            }
+            "send" => {
+                let client_id = params
+                    .get("client_id")
+                    .and_then(|c| c.as_str())
+                    .ok_or_else(|| json!({"error": "missing client_id"}));
+
+                match client_id {
+                    Ok(id) => {
+                        let data = params
+                            .get("data")
+                            .and_then(|d| d.as_str())
+                            .map(|s| s.as_bytes().to_vec());
+
+                        match data {
+                            Some(data) => match self.send_to(id, &data) {
+                                Ok(n) => json!({"success": true, "bytes_sent": n}),
+                                Err(e) => json!({"success": false, "error": e}),
+                            },
+                            None => json!({"success": false, "error": "missing data"}),
+                        }
+                    }
+                    Err(e) => e,
+                }
+            }
+            "recv" => {
+                let client_id = params
+                    .get("client_id")
+                    .and_then(|c| c.as_str())
+                    .ok_or_else(|| json!({"error": "missing client_id"}));
+
+                match client_id {
+                    Ok(id) => {
+                        let size = params
+                            .get("size")
+                            .and_then(|s| s.as_u64())
+                            .map(|s| s as usize)
+                            .unwrap_or(4096);
+                        match self.recv_from(id, size) {
+                            Ok(data) => json!({
+                                "success": true,
+                                "data": String::from_utf8_lossy(&data),
+                                "bytes": data.len()
+                            }),
+                            Err(e) => json!({"success": false, "error": e}),
+                        }
+                    }
+                    Err(e) => e,
+                }
+            }
+            "disconnect" => {
+                let client_id = params
+                    .get("client_id")
+                    .and_then(|c| c.as_str())
+                    .ok_or_else(|| json!({"error": "missing client_id"}));
+
+                match client_id {
+                    Ok(id) => match self.disconnect_client(id) {
+                        Ok(_) => json!({"success": true}),
+                        Err(e) => json!({"success": false, "error": e}),
+                    },
+                    Err(e) => e,
+                }
+            }
+            "status" => self.get_status(),
+            "list_clients" => {
+                let clients: Vec<Value> = self.clients.keys().map(|k| json!(k)).collect();
+                json!({"success": true, "clients": clients})
+            }
+            _ => json!({"success": false, "error": format!("unknown method: {}", method)}),
+        }
+    }
 }
 
 impl Component for TcpServer {
@@ -201,8 +435,20 @@ impl Component for TcpServer {
     }
 
     fn init(&mut self, config: Value) -> Result<(), String> {
-        self.config =
+        if let Some(server_config) = config.get("config") {
-            serde_json::from_value(config).map_err(|e| format!("Invalid config: {}", e))?;
+            self.config = serde_json::from_value(server_config.clone())
+                .map_err(|e| format!("Invalid config: {}", e))?;
+        } else {
+            self.config = serde_json::from_value(config.clone())
+                .map_err(|e| format!("Invalid config: {}", e))?;
+        }
+
+        if let Some(protocols) = config.get("protocols") {
+            let p: Vec<ProtocolConfig> = serde_json::from_value(protocols.clone())
+                .map_err(|e| format!("Invalid protocols: {}", e))?;
+            self.set_protocols(p)?;
+        }
+
         self.listen()?;
         Ok(())
     }
@@ -214,12 +460,21 @@ impl Component for TcpServer {
 
 impl TreeElement for TcpServer {
     fn get_type(&self) -> Value {
-        json!("TCPServer")
+        json!({
+            "type": "TCPServer",
+            "name": self.name,
+        })
     }
 
     fn send_message(&mut self, target: Value, message: Value) -> Value {
         match target {
             Value::Null => {
+                // Check for RPC call format
+                if message.get("method").is_some() {
+                    return self.handle_rpc(&message);
+                }
+
+                // Legacy string commands
                 if let Some(cmd) = message.as_str() {
                     match cmd {
                         "Listen" | "Start" => match self.listen() {
@@ -251,6 +506,9 @@ impl TreeElement for TcpServer {
                             }
                             Err(e) => json!({"success": false, "error": e.to_string()}),
                         }
+                    } else if obj.get("method").is_some() {
+                        let payload = Value::Object(obj.clone());
+                        self.handle_rpc(&payload)
                     } else {
                         json!(symbols::ERR_INVALID_COMMAND)
                     }
@@ -261,9 +519,42 @@ impl TreeElement for TcpServer {
             Value::String(subtarget) => match subtarget.as_str() {
                 "config" => json!(self.config),
                 "status" => self.get_status(),
+                "clients" => {
+                    let clients: Vec<Value> = self.clients.keys().map(|k| json!(k)).collect();
+                    json!(clients)
+                }
                 _ => json!(symbols::ERR_CHILD_NOT_FOUND),
             },
             _ => json!(symbols::ERR_INVALID_TARGET),
         }
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_server_creation() {
+        let server = TcpServer::new("test-server");
+        assert_eq!(server.name(), "test-server");
+        assert!(!server.is_listening());
+    }
+
+    #[test]
+    fn test_config_serialization() {
+        let server = TcpServer::with_config("test", TcpServerConfig::new(8080));
+        let json = serde_json::to_string(&server).unwrap();
+        assert!(json.contains("test"));
+        assert!(json.contains("8080"));
+    }
+
+    #[test]
+    fn test_rpc_status() {
+        let mut server = TcpServer::new("test");
+        let result = server.send_message(json!(null), json!({"method": "status"}));
+
+        let obj = result.as_object().unwrap();
+        assert!(obj.contains_key("listening"));
+    }
+}

ush-payload/src/main.rs

@@ -7,11 +7,16 @@ use std::io::{Read, Write};
 use std::net::TcpListener;
 use std::sync::mpsc;
 use std::thread;
+use std::time::Duration;
 
-use unshell::tree::{EndpointManager, TreeMessage};
+use serde_json::json;
+use unshell::tree::message::TreeMessage;
+use unshell::tree::protocols::{ProtocolConfig, ProtocolStack};
+use unshell::tree::tcp::{TcpClient, TcpServer};
+use unshell::tree::{ComponentRegistry, EndpointManager, TreeElement};
 
 fn main() {
-    println!("=== TCP Chain Test Harness ===\n");
+    println!("=== Tree Protocol Test Harness ===\n");
 
     // Test 1: Local TCP Server-Client loopback
     test_tcp_loopback();
@@ -19,9 +24,21 @@ fn main() {
     // Test 2: Tree message routing
     test_tree_message();
 
-    // Test 3: TreeMessage serialization
+    // Test 3: TreeMessage serialization (new API)
     test_message_serialization();
 
+    // Test 4: TCP Server with RPC
+    test_tcp_server();
+
+    // Test 5: TCP Client with RPC
+    test_tcp_client();
+
+    // Test 6: Protocol stacking
+    test_protocol_stack();
+
+    // Test 7: Component registry
+    test_component_registry();
+
     println!("\n=== All tests complete ===");
 }
 
@@ -29,7 +46,6 @@ fn main() {
 fn test_tcp_loopback() {
     println!("[Test 1] TCP Loopback Test");
 
-    // Start a TCP server in a thread
     let (tx, rx) = mpsc::channel();
 
     let server_thread = thread::spawn(move || {
@@ -37,24 +53,25 @@ fn test_tcp_loopback() {
         let addr = listener.local_addr().unwrap();
         tx.send(addr.port()).unwrap();
 
-        for stream in listener.incoming() {
+        // Accept one connection only
-            if let Ok(mut stream) = stream {
+        if let Ok((mut stream, _)) = listener.accept() {
-                let mut buf = [0u8; 1024];
+            let mut buf = [0u8; 1024];
-                if let Ok(n) = stream.read(&mut buf) {
+            if let Ok(n) = stream.read(&mut buf) {
-                    let response = b"Echo: ";
+                let response = b"Echo: ";
-                    let _ = stream.write(response);
+                let _ = stream.write(response);
-                    let _ = stream.write(&buf[..n]);
+                let _ = stream.write(&buf[..n]);
-                    let _ = stream.flush();
+                let _ = stream.flush();
-                }
             }
         }
     });
 
     let port = rx.recv().unwrap();
 
-    // Connect client
     let mut stream =
         std::net::TcpStream::connect(format!("127.0.0.1:{}", port)).expect("Failed to connect");
+    stream
+        .set_read_timeout(Some(Duration::from_millis(1000)))
+        .unwrap();
 
     let msg = b"Hello from client!";
     stream.write(msg).expect("Failed to write");
@@ -76,7 +93,6 @@ fn test_tree_message() {
 
     let mut endpoint = EndpointManager::new("endpoint-1");
 
-    // Test GetChildren
     let response = endpoint
         .branch_mut()
         .send_message(serde_json::Value::Null, serde_json::json!("GetChildren"));
@@ -84,13 +100,11 @@ fn test_tree_message() {
     let children = response.as_object().unwrap();
     println!("  Children: {:?}", children.keys().collect::<Vec<_>>());
 
-    // Test ID access
     let response = endpoint
         .branch_mut()
         .send_message(serde_json::json!("id"), serde_json::Value::Null);
     println!("  Endpoint ID: {:?}", response);
 
-    // Test logs queue
     let sender = endpoint.logs_sender().clone();
     sender.send(serde_json::json!("Test log entry")).unwrap();
 
@@ -102,24 +116,168 @@ fn test_tree_message() {
     println!("  ✓ Tree message test passed\n");
 }
 
-/// Test TreeMessage serialization
+/// Test TreeMessage serialization (new API)
 fn test_message_serialization() {
     println!("[Test 3] TreeMessage Serialization");
 
-    let msg = TreeMessage::new_req(
+    // Test new API
-        "msg-1",
+    let msg = TreeMessage::new("query")
-        vec!["endpoint1".to_string(), "shell".to_string()],
+        .to_target(["endpoint1", "shell"])
-        "Get",
+        .with_payload(json!({"key": "value"}));
-    );
 
     let json = serde_json::to_string_pretty(&msg).unwrap();
     println!("  Message: {}", json);
 
-    // Test response message
+    // Test response
-    let resp = TreeMessage::new_resp("resp-1", "msg-1", serde_json::json!("result data"));
+    let resp =
+        TreeMessage::new("response").with_payload(json!({"success": true, "result": "data"}));
 
     let json = serde_json::to_string_pretty(&resp).unwrap();
     println!("  Response: {}", json);
 
+    // Test RPC call
+    let rpc_msg = TreeMessage::new("rpc.call")
+        .to_target(["components", "tcp-client"])
+        .with_payload(json!({
+            "method": "connect",
+            "params": {"address": "127.0.0.1", "port": 8080}
+        }));
+
+    let json = serde_json::to_string_pretty(&rpc_msg).unwrap();
+    println!("  RPC Call: {}", json);
+
     println!("  ✓ Message serialization test passed\n");
 }
+
+/// Test TCP Server with RPC
+fn test_tcp_server() {
+    println!("[Test 4] TCP Server with RPC");
+
+    let mut server = TcpServer::new("test-server");
+
+    // Configure
+    let response = server.send_message(
+        json!(null),
+        json!({
+            "method": "status"
+        }),
+    );
+    println!("  Initial status: {:?}", response);
+
+    // Try to start listening
+    let response = server.send_message(
+        json!(null),
+        json!({
+            "method": "listen",
+            "params": {
+                "bind_address": "127.0.0.1",
+                "port": 0
+            }
+        }),
+    );
+    println!("  Listen result: {:?}", response);
+
+    // Get status after listening
+    let response = server.send_message(json!(null), json!({"method": "status"}));
+    println!("  Status after listen: {:?}", response);
+
+    println!("  ✓ TCP Server test passed\n");
+}
+
+/// Test TCP Client with RPC
+fn test_tcp_client() {
+    println!("[Test 5] TCP Client with RPC");
+
+    let mut client = TcpClient::new("test-client");
+
+    // Get initial status
+    let response = client.send_message(json!(null), json!({"method": "status"}));
+    println!("  Initial status: {:?}", response);
+
+    // Try to connect (will fail since no server, but tests the RPC)
+    let response = client.send_message(
+        json!(null),
+        json!({
+            "method": "connect",
+            "params": {"address": "127.0.0.1", "port": 65432}
+        }),
+    );
+    println!("  Connect result: {:?}", response);
+
+    // Get status after connect attempt
+    let response = client.send_message(json!(null), json!({"method": "status"}));
+    println!("  Status after connect: {:?}", response);
+
+    println!("  ✓ TCP Client test passed\n");
+}
+
+/// Test Protocol stacking
+fn test_protocol_stack() {
+    println!("[Test 6] Protocol Stacking");
+
+    // Create a stack: base64 -> tcp
+    let mut stack = ProtocolStack::new();
+    stack
+        .push(&ProtocolConfig::Base64(Default::default()))
+        .unwrap();
+    stack
+        .push(&ProtocolConfig::Tcp(Default::default()))
+        .unwrap();
+
+    println!("  Stack protocols: {:?}", stack.to_configs());
+
+    // Test encoding/decoding
+    let test_data = b"Hello, World!";
+    let encoded = stack.encode(test_data).unwrap();
+    println!(
+        "  Encoded ({} bytes): {:?}",
+        encoded.len(),
+        String::from_utf8_lossy(&encoded)
+    );
+
+    let decoded = stack.decode(&encoded).unwrap();
+    println!("  Decoded: {:?}", String::from_utf8_lossy(&decoded));
+
+    // Test with HTTP
+    let mut http_stack = ProtocolStack::new();
+    http_stack
+        .push(&ProtocolConfig::Base64(Default::default()))
+        .unwrap();
+    http_stack
+        .push(&ProtocolConfig::Http(Default::default()))
+        .unwrap();
+
+    let test_data = b"test message";
+    let encoded = http_stack.encode(test_data).unwrap();
+    println!(
+        "  HTTP+Base64 encoded: {:?}",
+        String::from_utf8_lossy(&encoded).lines().next()
+    );
+
+    println!("  ✓ Protocol stacking test passed\n");
+}
+
+/// Test Component Registry
+fn test_component_registry() {
+    println!("[Test 7] Component Registry");
+
+    let mut registry = ComponentRegistry::new();
+
+    // Create and register a TCP client component
+    let client = Box::new(TcpClient::new("tcp-client-1"));
+    registry.register(client).unwrap();
+
+    // List components
+    let list = registry.list();
+    println!("  Registered components: {:?}", list);
+
+    // Send RPC to component
+    let result = registry.send_to_component("tcp-client-1", json!({"method": "status"}));
+    println!("  Component status: {:?}", result);
+
+    // Send RPC via path
+    let result = registry.send_message(json!("rpc.tcp-client-1"), json!({"method": "status"}));
+    println!("  Via RPC path: {:?}", result);
+
+    println!("  ✓ Component registry test passed\n");
+}