Set cache control headers for the static files.

src/main.rs

@@ -1,11 +1,13 @@
 #![feature(exit_status_error)]
 use axum::http::header::CACHE_CONTROL;
-use axum::http::HeaderMap;
+use axum::http::HeaderValue;
 use axum::response::IntoResponse;
 use axum::{http::StatusCode, routing::post, Json, Router};
 use owner_tree::build_owner_tree;
 use parse::emacs_parse_org_document;
+use tower::ServiceBuilder;
 use tower_http::services::{ServeDir, ServeFile};
+use tower_http::set_header::SetResponseHeaderLayer;
 
 mod error;
 mod owner_tree;
@@ -14,10 +16,20 @@ mod sexp;
 
 #[tokio::main]
 async fn main() {
-    let serve_dir = ServeDir::new("static").not_found_service(ServeFile::new("static/index.html"));
+    let static_files_service = {
+        let serve_dir =
+            ServeDir::new("static").not_found_service(ServeFile::new("static/index.html"));
+
+        ServiceBuilder::new()
+            .layer(SetResponseHeaderLayer::if_not_present(
+                CACHE_CONTROL,
+                HeaderValue::from_static("public, max-age=120"),
+            ))
+            .service(serve_dir)
+    };
     let app = Router::new()
         .route("/parse", post(parse_org_mode))
-        .fallback_service(serve_dir);
+        .fallback_service(static_files_service);
 
     let listener = tokio::net::TcpListener::bind("0.0.0.0:3000").await.unwrap();
     axum::serve(listener, app).await.unwrap();
@@ -34,9 +46,3 @@ async fn _parse_org_mode(body: String) -> Result<impl IntoResponse, Box<dyn std:
     let owner_tree = build_owner_tree(body.as_str(), ast.as_str()).map_err(|e| e.to_string())?;
     Ok((StatusCode::OK, Json(owner_tree)))
 }
-
-fn no_cache_headers() -> HeaderMap {
-    let mut headers = HeaderMap::new();
-    headers.insert(CACHE_CONTROL, "public, max-age=120".parse().unwrap());
-    headers
-}