simple-web-app

commit d824539220c6ce5105a4937b7b4c3c0c04ce423c
parent b29468f52db172037b861e7c6a907d2d66dfaf11
Author: Silas Brack <silasbrack@gmail.com>
Date:   Thu, 11 Jun 2026 12:30:33 +0200

feat: add SSE helper module for Datastar-compliant responses

Adds src/sse.rs with helpers that format proper SSE
datastar-patch-elements events per the Datastar SSE spec,
replacing the non-standard custom header approach.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Diffstat:
M
src/main.rs
 | 
1
+
A
src/sse.rs
 | 
35
+++++++++++++++++++++++++++++++++++

2 files changed, 36 insertions(+), 0 deletions(-)
diff --git a/src/main.rs b/src/main.rs
@@ -3,6 +3,7 @@ mod db;
 mod error;
 mod handlers;
 mod routes;
+mod sse;
 mod state;
 mod templates;
 mod trailbase;
diff --git a/src/sse.rs b/src/sse.rs
@@ -0,0 +1,35 @@
+use axum::{body::Body, http::{StatusCode, header}, response::Response};
+
+pub fn patch_elements(html: &str) -> Response {
+    patch_elements_with_options(html, None, None)
+}
+
+pub fn patch_elements_with_selector(html: &str, selector: &str) -> Response {
+    patch_elements_with_options(html, Some(selector), None)
+}
+
+fn patch_elements_with_options(
+    html: &str,
+    selector: Option<&str>,
+    mode: Option<&str>,
+) -> Response {
+    let mut data_lines = Vec::new();
+    if let Some(sel) = selector {
+        data_lines.push(format!("data: selector {sel}"));
+    }
+    if let Some(m) = mode {
+        data_lines.push(format!("data: mode {m}"));
+    }
+    for line in html.lines() {
+        data_lines.push(format!("data: elements {line}"));
+    }
+
+    let body = format!("event: datastar-patch-elements\n{}\n\n", data_lines.join("\n"));
+
+    Response::builder()
+        .status(StatusCode::OK)
+        .header(header::CONTENT_TYPE, "text/event-stream")
+        .header(header::CACHE_CONTROL, "no-cache")
+        .body(Body::from(body))
+        .unwrap()
+}