Add flush to arbitrary file

src/backend.rs

@@ -24,6 +24,7 @@ use std::{
     collections::{hash_map::Entry, HashMap, VecDeque},
     future::IntoFuture,
     marker::PhantomData,
+    path::Path,
     pin::Pin,
     sync::{
         mpsc::{channel as oneshot_channel, Sender as OneshotSender},
@@ -656,6 +657,11 @@ impl SharedBackend {
     pub fn flush_cache(&self) {
         self.cache.0.flush();
     }
+
+    /// Flushes the DB to a specific file
+    pub fn flush_cache_to(&self, cache_path: &Path) {
+        self.cache.0.flush_to(cache_path);
+    }
 }
 
 impl DatabaseRef for SharedBackend {

src/cache.rs

@@ -10,7 +10,7 @@ use std::{
     collections::{BTreeSet, HashMap},
     fs,
     io::{BufWriter, Write},
-    path::PathBuf,
+    path::{Path, PathBuf},
     sync::Arc,
 };
 use url::Url;
@@ -382,6 +382,13 @@ impl JsonBlockCacheDB {
     #[instrument(level = "warn", skip_all, fields(path = ?self.cache_path))]
     pub fn flush(&self) {
         let Some(path) = &self.cache_path else { return };
+        self.flush_to(path.as_path());
+    }
+
+    /// Flushes the DB to a specific file
+    pub fn flush_to(&self, cache_path: &Path) {
+        let path: &Path = cache_path;
+
         trace!(target: "cache", "saving json cache");
 
         if let Some(parent) = path.parent() {