fix db serialization

patch-db-util/src/main.rs

@@ -25,7 +25,7 @@ async fn main() {
         Some(("dump", matches)) => {
             let path = matches.value_of("PATH").unwrap();
             let db = patch_db::PatchDb::open(path).await.unwrap();
-            let dump = db.dump().await;
+            let dump = db.dump().await.unwrap();
             serde_json::to_writer_pretty(&mut std::io::stdout(), &dump.value).unwrap();
             println!();
         }
@@ -36,7 +36,6 @@ async fn main() {
             db.put(
                 &JsonPointer::<&str, (&[PtrSegment], &[PtrSegment])>::default(),
                 &value,
-                None,
             )
             .await
             .unwrap();

patch-db/src/store.rs

@@ -96,7 +96,8 @@ impl Store {
                 OpenOptions::new()
                     .create(true)
                     .read(true)
-                    .append(true)
+                    .write(true)
+                    .truncate(false)
                     .open(&path)?,
                 fd_lock_rs::LockType::Exclusive,
                 true,
@@ -199,6 +200,7 @@ impl Store {
         self.file.flush().await?;
         self.file.sync_all().await?;
         tokio::fs::remove_file(&bak).await?;
+        self.file_cursor = self.file.stream_position().await?;
         Ok(())
     }
     pub(crate) async fn apply(&mut self, patch: DiffPatch) -> Result<Option<Arc<Revision>>, Error> {