fix up pg replication example

examples/pg_replication/main.rs

@@ -37,13 +37,12 @@ use axum::{
     Router,
 };
 use maud::{html, Markup, DOCTYPE};
-use serde::Deserialize;
 use sqlx::FromRow;
 use uuid::Uuid;
 
 use livevue_rs::{
     pg_replication::{pg_table_key, PgReplicationConfig, PgReplicationListener},
-    server::{ingest_signals, ActionParams, AppState, SharedState},
+    server::{ingest_signals, patch_signal, AppState, SharedState},
     spawn_fanout, RenderContext, Store,
 };
 
@@ -112,6 +111,7 @@ async fn render_page(cx: &mut RenderContext, rs: &RenderState) -> anyhow::Result
         .await?;
 
     let new_msg = cx.signal("newMsg", livevue_rs::global());
+    let _conn_id_signal = cx.signal("connId", livevue_rs::global());
 
     Ok(html! {
         div #app {
@@ -127,11 +127,10 @@ async fn render_page(cx: &mut RenderContext, rs: &RenderState) -> anyhow::Result
                     type="text"
                     placeholder="Type a message…"
                     data-bind=(new_msg.name)
-                    data-on:keydown="{if (event.key === 'Enter') $post('/action/post_message')}"
+                    data-on:keydown="{if (event.key === 'Enter') @post('/action/post_message')}"
                     ;
                 button
-                    data-on:click="$post('/action/post_message')"
-                    data-attr=(format!("{{disabled: {}.trim() === ''}}", new_msg.val))
+                    data-on:click="@post('/action/post_message')"
                     { "Send" }
             }
 
@@ -179,16 +178,14 @@ fn page_shell(conn_id: Uuid, signals_json: &str, inner: &Markup) -> String {
                 // DataStar SDK (loaded from CDN for the example)
                 script
                     type="module"
-                    src="https://cdn.jsdelivr.net/gh/starfederation/datastar@v1.0.0-beta.11/bundles/datastar.js"
+                    src="https://cdn.jsdelivr.net/gh/starfederation/datastar@1.0.0-RC.8/bundles/datastar.js"
                     {}
             }
-            body {
-                div
-                    data-signals=(signals_json)
-                    data-on:load=(format!("@get('/sse?conn={conn_id}')"))
-                {
-                    (inner)
-                }
+            body
+                data-signals=(signals_json)
+                data-init=(format!("@get('/sse?conn={conn_id}')"))
+            {
+                (inner)
             }
         }
     }
@@ -202,7 +199,7 @@ fn page_shell(conn_id: Uuid, signals_json: &str, inner: &Markup) -> String {
 async fn index_handler(State(state): State<(SharedState, RenderState)>) -> impl IntoResponse {
     let (app_state, rs) = &state;
     let conn_id = Uuid::new_v4();
-    let signals_json = r#"{"newMsg":""}"#;
+    let signals_json = &format!(r#"{{"newMsg":"","connId":"{}"}}"#, conn_id);
     app_state.connections.insert(conn_id, {
         // We need a sender for the connection, but the SSE handler will replace
         // it.  Use a dummy channel that immediately drops.
@@ -214,7 +211,7 @@ async fn index_handler(State(state): State<(SharedState, RenderState)>) -> impl
         .update_signals(&conn_id, signals_json.to_string());
 
     let mut cx =
-        RenderContext::new(conn_id, livevue_rs::SignalStore::from_json(serde_json::json!({"newMsg": ""})), Default::default(), app_state.store.clone());
+        RenderContext::new(conn_id, livevue_rs::SignalStore::from_json(serde_json::json!({"newMsg": "", "connId": conn_id.to_string()})), Default::default(), app_state.store.clone());
 
     let inner = render_page(&mut cx, rs).await.unwrap_or_else(|e| {
         html! { p { "Render error: " (e) } }
@@ -232,18 +229,17 @@ async fn sse_adapter(
     livevue_rs::sse_handler(State(state.0), query).await
 }
 
-#[derive(Deserialize)]
-struct PostMessageBody {
-    #[serde(rename = "newMsg")]
-    new_msg: Option<String>,
-}
-
 async fn post_message_handler(
     State(state): State<(SharedState, RenderState)>,
-    axum::extract::Query(params): axum::extract::Query<ActionParams>,
     Json(body): Json<serde_json::Value>,
 ) -> impl IntoResponse {
-    let signals = ingest_signals(&state.0, params.conn, body);
+    let conn_id = body
+        .get("connId")
+        .and_then(|v| v.as_str())
+        .and_then(|s| s.parse().ok())
+        .unwrap_or_else(Uuid::new_v4);
+
+    let signals = ingest_signals(&state.0, conn_id, body);
     let msg: String = signals
         .get("newMsg")
         .and_then(|v| v.as_str().map(|s| s.trim().to_string()))
@@ -262,6 +258,9 @@ async fn post_message_handler(
         return StatusCode::INTERNAL_SERVER_ERROR;
     }
 
+    // Update the stored signals to reset the input field
+    patch_signal(&state.0, &conn_id, "newMsg", serde_json::json!(""));
+
     // Note: we do NOT call store.publish() here — the PgReplicationListener
     // will detect the INSERT through the WAL stream and fire the invalidation
     // automatically.  This demonstrates the key value of the module: mutations
@@ -384,4 +383,4 @@ async fn main() -> anyhow::Result<()> {
     axum::serve(listener_tcp, app).await?;
 
     Ok(())
-}
+}