Return 504 when a file is missing to be by-spec

The spec defines that the media endpoints should return 504 when a file
is not-yet-uploaded, which has been interpreted to include when a file
was deleted. Modifies the /media/v3/download/ and /media/r0/thumbnail
endpoints.

src/api/client_server/media.rs

@@ -250,7 +250,7 @@ async fn get_content_route_ruma(
             cross_origin_resource_policy: Some("cross-origin".to_owned()),
         })
     } else {
-        Err(Error::BadRequest(ErrorKind::NotFound, "Media not found."))
+        Err(Error::BadRequest(ErrorKind::NotYetUploaded, "Media not found."))
     }
 }
 
@@ -415,6 +415,6 @@ async fn get_content_thumbnail_route_ruma(
             cross_origin_resource_policy: Some("cross-origin".to_owned()),
         })
     } else {
-        Err(Error::BadRequest(ErrorKind::NotFound, "Media not found."))
+        Err(Error::BadRequest(ErrorKind::NotYetUploaded, "Media not found."))
     }
 }

src/service/media.rs

@@ -3,7 +3,7 @@ use std::io::Cursor;
 use image::imageops::FilterType;
 use tokio::{
     fs::File,
-    io::{AsyncReadExt, AsyncWriteExt, BufReader},
+    io::{AsyncReadExt, AsyncWriteExt},
 };
 use tracing::{debug, warn};
 
@@ -88,15 +88,17 @@ impl Service {
             self.db.search_file_metadata(mxc, 0, 0)
         {
             let path = services().globals.get_media_file(&key);
-            let mut file = Vec::new();
-            BufReader::new(File::open(path).await?)
-                .read_to_end(&mut file)
-                .await?;
+            let mut file_data = Vec::new();
+            let Ok(mut file) = File::open(path).await else {
+                return Ok(None);
+            };
+
+            file.read_to_end(&mut file_data).await?;
 
             Ok(Some(FileMeta {
                 content_disposition,
                 content_type,
-                file,
+                file: file_data,
             }))
         } else {
             Ok(None)

src/utils/error.rs

@@ -98,9 +98,9 @@ impl Error {
     pub(crate) fn to_response(&self) -> Ra<UiaaResponse> {
         use ErrorKind::{
             Forbidden, GuestAccessForbidden, LimitExceeded, MissingToken,
-            NotFound, ThreepidAuthFailed, ThreepidDenied, TooLarge,
-            Unauthorized, Unknown, UnknownToken, Unrecognized, UserDeactivated,
-            WrongRoomKeysVersion,
+            NotFound, NotYetUploaded, ThreepidAuthFailed, ThreepidDenied,
+            TooLarge, Unauthorized, Unknown, UnknownToken, Unrecognized,
+            UserDeactivated, WrongRoomKeysVersion,
         };
 
         if let Self::Uiaa(uiaainfo) = self {
@@ -142,6 +142,7 @@ impl Error {
                         ..
                     } => StatusCode::TOO_MANY_REQUESTS,
                     TooLarge => StatusCode::PAYLOAD_TOO_LARGE,
+                    NotYetUploaded => StatusCode::GATEWAY_TIMEOUT,
                     _ => StatusCode::BAD_REQUEST,
                 },
             ),