feat: update cache

src/mito2/src/cache/file_cache.rs

@@ -113,7 +113,7 @@ impl FileCache {
             return None;
         }
 
-        let file_path = cache_file_path(&self.file_dir, key);
+        let file_path = self.cache_file_path(key);
         match self.local_store.reader(&file_path).await {
             Ok(reader) => {
                 CACHE_HIT.with_label_values(&[FILE_TYPE]).inc();
@@ -133,7 +133,7 @@ impl FileCache {
 
     /// Removes a file from the cache explicitly.
     pub(crate) async fn remove(&self, key: IndexKey) {
-        let file_path = cache_file_path(&self.file_dir, key);
+        let file_path = self.cache_file_path(key);
         if let Err(e) = self.local_store.delete(&file_path).await {
             warn!(e; "Failed to delete a cached file {}", file_path);
         }
@@ -179,6 +179,16 @@ impl FileCache {
 
         Ok(())
     }
+
+    /// Returns the cache file path for the key.
+    pub(crate) fn cache_file_path(&self, key: IndexKey) -> String {
+        cache_file_path(&self.file_dir, key)
+    }
+
+    /// Returns the local store of the file cache.
+    pub(crate) fn local_store(&self) -> ObjectStore {
+        self.local_store.clone()
+    }
 }
 
 /// Key of file cache index.