1 files changed, 44 insertions, 4 deletions

diff --git a/server/src/routes/ui/mod.rs b/server/src/routes/ui/mod.rs
index 62c8aa8..f566f6d 100644
--- a/server/src/routes/ui/mod.rs
+++ b/server/src/routes/ui/mod.rs
@@ -3,24 +3,32 @@
     which is licensed under the GNU Affero General Public License (version 3); see /COPYING.
     Copyright (C) 2023 metamuffin <metamuffin.org>
 */
+use log::debug;
 use markup::Render;
 use rocket::{
     futures::FutureExt,
-    http::ContentType,
+    http::{ContentType, Header, Status},
     response::{self, Responder},
     Request, Response,
 };
-use std::{future::Future, io::Cursor, pin::Pin};
-use tokio::io::AsyncRead;
+use std::{
+    collections::hash_map::DefaultHasher,
+    future::Future,
+    hash::{Hash, Hasher},
+    io::Cursor,
+    os::unix::prelude::MetadataExt,
+    pin::Pin,
+};
+use tokio::{fs::File, io::AsyncRead};
 
 pub mod account;
+pub mod browser;
 pub mod error;
 pub mod home;
 pub mod layout;
 pub mod node;
 pub mod player;
 pub mod style;
-pub mod browser;
 
 pub struct HtmlTemplate<'a>(pub markup::DynRender<'a>);
 
@@ -52,3 +60,35 @@ impl AsyncRead for Defer {
         }
     }
 }
+
+pub struct CacheControlFile(File, String);
+impl CacheControlFile {
+    pub async fn new(f: File) -> Self {
+        let meta = f.metadata().await.unwrap();
+        let modified = meta.mtime();
+        let mut h = DefaultHasher::new();
+        modified.hash(&mut h);
+        let tag = format!("{:0>16x}", h.finish());
+        Self(f, tag)
+    }
+}
+impl<'r> Responder<'r, 'static> for CacheControlFile {
+    fn respond_to(self, req: &'r Request<'_>) -> response::Result<'static> {
+        let Self(file, tag) = self;
+        if req.headers().get_one("if-none-match") == Some(&tag) {
+            debug!("file cache: not modified");
+            Response::build()
+                .status(Status::NotModified)
+                .header(Header::new("cache-control", "private"))
+                .ok()
+        } else {
+            debug!("file cache: transfer");
+            Response::build()
+                .status(Status::Ok)
+                .header(Header::new("cache-control", "private"))
+                .header(Header::new("etag", tag))
+                .streamed_body(file)
+                .ok()
+        }
+    }
+}