persistent room topics (#50)

Reviewed-on: lavina/lavina#50

crates/lavina-core/src/repo/room.rs

@@ -30,4 +30,19 @@ impl Storage {
 
         Ok(())
     }
+
+    pub async fn set_room_topic(&mut self, id: u32, topic: &str) -> Result<()> {
+        let mut executor = self.conn.lock().await;
+        sqlx::query(
+            "update rooms
+            set topic = ?
+            where id = ?;",
+        )
+        .bind(topic)
+        .bind(id)
+        .fetch_optional(&mut *executor)
+        .await?;
+
+        Ok(())
+    }
 }

crates/lavina-core/src/room.rs

@@ -182,7 +182,9 @@ impl RoomHandle {
 
     pub async fn set_topic(&self, changer_id: &PlayerId, new_topic: Str) {
         let mut lock = self.0.write().await;
+        let storage_id = lock.storage_id;
         lock.topic = new_topic.clone();
+        lock.storage.set_room_topic(storage_id, &new_topic).await.unwrap();
         let update = Updates::RoomTopicChanged {
             room_id: lock.room_id.clone(),
             new_topic: new_topic.clone(),