Make Cache trait compat with Moka

Author: nyurik

src/async_reader.rs

@@ -157,13 +157,13 @@ impl<B: AsyncBackend + Sync + Send, C: DirectoryCache + Sync + Send> AsyncPmTile
         // and it allows directory to be cached later without cloning it first.
         let offset = (self.header.leaf_offset + entry.offset) as _;
 
-        let entry = match self.cache.get_dir_entry(offset, tile_id) {
+        let entry = match self.cache.get_dir_entry(offset, tile_id).await {
             DirCacheResult::NotCached => {
                 // Cache miss - read from backend
                 let length = entry.length as _;
                 let dir = self.read_directory(offset, length).await.ok()?;
                 let entry = dir.find_tile_id(tile_id).cloned();
-                self.cache.insert_dir(offset, dir);
+                self.cache.insert_dir(offset, dir).await;
                 entry
             }
             DirCacheResult::NotFound => None,

src/cache.rs

@@ -1,6 +1,8 @@
 use std::collections::HashMap;
 use std::sync::{Arc, Mutex};
 
+use async_trait::async_trait;
+
 use crate::directory::{DirEntry, Directory};
 
 pub enum DirCacheResult {
@@ -19,25 +21,27 @@ impl From<Option<&DirEntry>> for DirCacheResult {
 }
 
 /// A cache for PMTiles directories.
+#[async_trait]
 pub trait DirectoryCache {
     /// Get a directory from the cache, using the offset as a key.
-    fn get_dir_entry(&self, offset: usize, tile_id: u64) -> DirCacheResult;
+    async fn get_dir_entry(&self, offset: usize, tile_id: u64) -> DirCacheResult;
 
     /// Insert a directory into the cache, using the offset as a key.
     /// Note that cache must be internally mutable.
-    fn insert_dir(&self, offset: usize, directory: Directory);
+    async fn insert_dir(&self, offset: usize, directory: Directory);
 }
 
 pub struct NoCache;
 
+#[async_trait]
 impl DirectoryCache for NoCache {
     #[inline]
-    fn get_dir_entry(&self, _offset: usize, _tile_id: u64) -> DirCacheResult {
+    async fn get_dir_entry(&self, _offset: usize, _tile_id: u64) -> DirCacheResult {
         DirCacheResult::NotCached
     }
 
     #[inline]
-    fn insert_dir(&self, _offset: usize, _directory: Directory) {}
+    async fn insert_dir(&self, _offset: usize, _directory: Directory) {}
 }
 
 /// A simple HashMap-based implementation of a PMTiles directory cache.
@@ -46,15 +50,16 @@ pub struct HashMapCache {
     pub cache: Arc<Mutex<HashMap<usize, Directory>>>,
 }
 
+#[async_trait]
 impl DirectoryCache for HashMapCache {
-    fn get_dir_entry(&self, offset: usize, tile_id: u64) -> DirCacheResult {
+    async fn get_dir_entry(&self, offset: usize, tile_id: u64) -> DirCacheResult {
         if let Some(dir) = self.cache.lock().unwrap().get(&offset) {
             return dir.find_tile_id(tile_id).into();
         }
         DirCacheResult::NotCached
     }
 
-    fn insert_dir(&self, offset: usize, directory: Directory) {
+    async fn insert_dir(&self, offset: usize, directory: Directory) {
         self.cache.lock().unwrap().insert(offset, directory);
     }
 }

src/directory.rs

@@ -5,6 +5,7 @@ use varint_rs::VarintReader;
 
 use crate::error::Error;
 
+#[derive(Clone)]
 pub struct Directory {
     entries: Vec<DirEntry>,
 }