fix: fetch more than one prev event

src/server_server.rs

@@ -867,17 +867,19 @@ pub async fn handle_incoming_pdu<'a>(
         .map_err(|_| "Failed to ask database for event.".to_owned())?
         .ok_or_else(|| "Failed to find create event in db.".to_owned())?;
 
-    let (incoming_pdu, val) = handle_outlier_pdu(origin, &create_event, event_id, room_id, value, db, pub_key_map).await?;
+    let (incoming_pdu, val) = handle_outlier_pdu(
+        origin,
+        &create_event,
+        event_id,
+        room_id,
+        value,
+        db,
+        pub_key_map,
+    )
+    .await?;
 
     // 8. if not timeline event: stop
-    if !is_timeline_event
+    if !is_timeline_event {
-        || incoming_pdu.origin_server_ts
-            < db.rooms
-                .first_pdu_in_room(&room_id)
-                .map_err(|_| "Error loading first room event.".to_owned())?
-                .expect("Room exists")
-                .origin_server_ts
-    {
         return Ok(None);
     }
 
@@ -893,16 +895,45 @@ pub async fn handle_incoming_pdu<'a>(
             &room_id,
             pub_key_map,
         )
-        .await.pop() {
+        .await
+        .pop()
+        {
+            if incoming_pdu.origin_server_ts
+                > db.rooms
+                    .first_pdu_in_room(&room_id)
+                    .map_err(|_| "Error loading first room event.".to_owned())?
+                    .expect("Room exists")
+                    .origin_server_ts
+            {
+                todo_outlier_stack.extend(pdu.prev_events.iter().cloned());
                 todo_timeline_stack.push((pdu, json));
             }
         }
+    }
 
     while let Some(prev) = todo_timeline_stack.pop() {
-        upgrade_outlier_to_timeline_pdu(prev.0, prev.1, &create_event, origin, db, room_id, pub_key_map).await?;
+        upgrade_outlier_to_timeline_pdu(
+            prev.0,
+            prev.1,
+            &create_event,
+            origin,
+            db,
+            room_id,
+            pub_key_map,
+        )
+        .await?;
     }
 
-    upgrade_outlier_to_timeline_pdu(incoming_pdu, val, &create_event, origin, db, room_id, pub_key_map).await
+    upgrade_outlier_to_timeline_pdu(
+        incoming_pdu,
+        val,
+        &create_event,
+        origin,
+        db,
+        room_id,
+        pub_key_map,
+    )
+    .await
 }
 
 fn handle_outlier_pdu<'a>(
@@ -913,7 +944,8 @@ fn handle_outlier_pdu<'a>(
     value: BTreeMap<String, CanonicalJsonValue>,
     db: &'a Database,
     pub_key_map: &'a RwLock<BTreeMap<String, BTreeMap<String, String>>>,
-) -> AsyncRecursiveType<'a, StdResult<(Arc<PduEvent>, BTreeMap<String, CanonicalJsonValue>), String>> {
+) -> AsyncRecursiveType<'a, StdResult<(Arc<PduEvent>, BTreeMap<String, CanonicalJsonValue>), String>>
+{
     Box::pin(async move {
         let start_time = Instant::now();
 
@@ -1064,7 +1096,6 @@ fn handle_outlier_pdu<'a>(
 
         Ok((incoming_pdu, val))
     })
-
 }
 
 async fn upgrade_outlier_to_timeline_pdu(
@@ -1120,7 +1151,8 @@ async fn upgrade_outlier_to_timeline_pdu(
             })
             .collect::<HashMap<_, _>>();
 
-                let prev_pdu = db.rooms.get_pdu(prev_event).ok().flatten().ok_or_else(|| {
+            let prev_pdu =
+                db.rooms.get_pdu(prev_event).ok().flatten().ok_or_else(|| {
                     "Could not find prev event, but we know the state.".to_owned()
                 })?;
 
@@ -1163,15 +1195,19 @@ async fn upgrade_outlier_to_timeline_pdu(
 
                 let mut state = HashMap::new();
                 for (pdu, _) in state_vec {
-                        match state.entry((pdu.kind.clone(), pdu.state_key.clone().ok_or_else(|| "Found non-state pdu in state events.".to_owned())?)) {
+                    match state.entry((
+                        pdu.kind.clone(),
+                        pdu.state_key
+                            .clone()
+                            .ok_or_else(|| "Found non-state pdu in state events.".to_owned())?,
+                    )) {
                         Entry::Vacant(v) => {
                             v.insert(pdu);
                         }
-                            Entry::Occupied(_) => {
+                        Entry::Occupied(_) => return Err(
-                                return Err(
+                            "State event's type and state_key combination exists multiple times."
-                                    "State event's type and state_key combination exists multiple times.".to_owned(),
+                                .to_owned(),
-                                )
+                        ),
-                            }
                     }
                 }
 
@@ -1228,7 +1264,6 @@ async fn upgrade_outlier_to_timeline_pdu(
         None
     };
 
-
     if !state_res::event_auth::auth_check(
         &room_version,
         &incoming_pdu,
@@ -1535,9 +1570,7 @@ pub(crate) fn fetch_and_handle_outliers<'a>(
                             )
                             .await
                             {
-                                Ok((pdu, json)) => {
+                                Ok((pdu, json)) => (pdu, Some(json)),
-                                    (pdu, Some(json))
-                                }
                                 Err(e) => {
                                     warn!("Authentication of event {} failed: {:?}", id, e);
                                     back_off(id.clone());