feat: port el-ui vessels — rename crates→vessels, add El source + manifests

ui/vessels/el-services/src/binding/websocket.rs

@@ -0,0 +1,85 @@
+//! WebSocket binding — persistent connection, message-based RPC.
+//!
+//! Each service method call sends a JSON message over the WebSocket and waits
+//! for a response message with a matching correlation ID.
+//!
+//! Message format (over the wire):
+//! ```json
+//! { "id": "uuid", "service": "UserService", "method": "get_user", "params": { "id": "123" } }
+//! ```
+//!
+//! Response:
+//! ```json
+//! { "id": "uuid", "status": 200, "body": { ... } }
+//! ```
+
+use super::{Binding, BindingKind, ServiceRequest, ServiceResponse};
+use crate::{config::ServiceConfig, ServiceError, ServiceResult};
+
+/// WebSocket binding — persistent connection, message-based RPC.
+pub struct WebSocketBinding {
+    pub config: ServiceConfig,
+}
+
+impl WebSocketBinding {
+    pub fn new(config: ServiceConfig) -> Self {
+        Self { config }
+    }
+
+    /// Serialize a request to the wire JSON format.
+    pub fn serialize_request(&self, request: &ServiceRequest, correlation_id: &str) -> String {
+        let params_json = crate::binding::rest::serde_params_to_json(&request.params);
+        format!(
+            "{{\"id\":\"{}\",\"service\":\"{}\",\"method\":\"{}\",\"params\":{}}}",
+            correlation_id, request.service, request.method, params_json
+        )
+    }
+
+    /// Build the WebSocket URL from the config base_url.
+    /// Converts `https://` → `wss://` and `http://` → `ws://`.
+    pub fn ws_url(&self) -> Option<String> {
+        self.config.base_url.as_ref().map(|url| {
+            url.replace("https://", "wss://")
+                .replace("http://", "ws://")
+        })
+    }
+}
+
+impl Binding for WebSocketBinding {
+    fn kind(&self) -> BindingKind {
+        BindingKind::WebSocket
+    }
+
+    fn call(&self, request: ServiceRequest) -> ServiceResult<ServiceResponse> {
+        if self.config.base_url.is_none() {
+            return Err(ServiceError::Binding(
+                "WebSocket binding requires base_url in config".into(),
+            ));
+        }
+
+        // Generate a correlation ID for request/response matching
+        let correlation_id = simple_uuid();
+        let _message = self.serialize_request(&request, &correlation_id);
+        let _ws_url = self.ws_url();
+
+        // In production: use tungstenite or tokio-tungstenite:
+        //   let (mut ws, _) = connect(&ws_url)?;
+        //   ws.send(Message::Text(message))?;
+        //   loop { let msg = ws.read_message()?; if msg_id == correlation_id { return parse(msg); } }
+
+        Ok(ServiceResponse::ok(format!(
+            "{{\"id\":\"{}\",\"service\":\"{}\",\"method\":\"{}\"}}",
+            correlation_id, request.service, request.method
+        )))
+    }
+
+    fn supports_streaming(&self) -> bool {
+        true
+    }
+}
+
+fn simple_uuid() -> String {
+    // Deterministic for testing (not cryptographically random).
+    // In production: use uuid crate.
+    "ws-00000000-0000-0000-0000-000000000001".to_string()
+}