update Storage fn bounds

Author: MarinPostma

libsql-wal/src/storage/backend/mod.rs

@@ -42,19 +42,19 @@ pub trait Backend: Send + Sync + 'static {
         segment_index: Vec<u8>,
     ) -> impl Future<Output = Result<()>> + Send;
 
-    async fn find_segment(
+    fn find_segment(
         &self,
         config: &Self::Config,
         namespace: &NamespaceName,
         frame_no: u64,
-    ) -> Result<SegmentKey>;
+    ) -> impl Future<Output = Result<SegmentKey>> + Send;
 
-    async fn fetch_segment_index(
+    fn fetch_segment_index(
         &self,
         config: &Self::Config,
         namespace: &NamespaceName,
         key: &SegmentKey,
-    ) -> Result<Map<Arc<[u8]>>>;
+    ) -> impl Future<Output = Result<Map<Arc<[u8]>>>> + Send;
 
     /// Fetch a segment for `namespace` containing `frame_no`, and writes it to `dest`.
     async fn fetch_segment_data_to_file(
@@ -67,12 +67,12 @@ pub trait Backend: Send + Sync + 'static {
 
     // this method taking self: Arc<Self> is an infortunate consequence of rust type system making
     // impl FileExt variant with all the arguments, with no escape hatch...
-    async fn fetch_segment_data(
+    fn fetch_segment_data(
         self: Arc<Self>,
         config: Self::Config,
         namespace: NamespaceName,
         key: SegmentKey,
-    ) -> Result<impl FileExt>;
+    ) -> impl Future<Output = Result<impl FileExt>> + Send;
 
     // /// Fetch a segment for `namespace` containing `frame_no`, and writes it to `dest`.
     async fn fetch_segment(

libsql-wal/src/storage/mod.rs

@@ -164,30 +164,36 @@ pub trait Storage: Send + Sync + 'static {
         config_override: Option<Self::Config>,
     ) -> Result<()>;
 
-    async fn find_segment(
+    fn find_segment(
         &self,
         namespace: &NamespaceName,
         frame_no: u64,
-    ) -> Result<SegmentKey>;
         config_override: Option<Self::Config>,
+    ) -> impl Future<Output = Result<SegmentKey>> + Send;
 
-    async fn fetch_segment_index(
+    fn fetch_segment_index(
         &self,
         namespace: &NamespaceName,
         key: &SegmentKey,
-    ) -> Result<Map<Arc<[u8]>>>;
         config_override: Option<Self::Config>,
+    ) -> impl Future<Output = Result<Map<Arc<[u8]>>>> + Send;
+
+    fn fetch_segment_data(
+        &self,
+        namespace: &NamespaceName,
+        key: &SegmentKey,
         config_override: Option<Self::Config>,
+    ) -> impl Future<Output = Result<CompactedSegment<impl FileExt>>> + Send;
 
-    async fn fetch_segment_data(
     fn shutdown(&self) -> impl Future<Output = ()> + Send {
         async { () }
     }
+    fn fetch_segment_index(
         &self,
         namespace: &NamespaceName,
         key: &SegmentKey,
-    ) -> Result<CompactedSegment<impl FileExt>>;
         config_override: Option<Self::Config>,
+    ) -> impl Future<Output = Result<Map<Arc<[u8]>>>> + Send {
 }
 
 /// a placeholder storage that doesn't store segment