add helper WalSession RAII-wrapper

packages/turso-sync/src/wal_session.rs

@@ -0,0 +1,40 @@
+use crate::Result;
+
+pub struct WalSession<'a> {
+    conn: &'a turso::Connection,
+    in_txn: bool,
+}
+
+impl<'a> WalSession<'a> {
+    pub fn new(conn: &'a turso::Connection) -> Self {
+        Self {
+            conn,
+            in_txn: false,
+        }
+    }
+    pub fn begin(&mut self) -> Result<()> {
+        assert!(!self.in_txn);
+        self.conn.wal_insert_begin()?;
+        self.in_txn = true;
+        Ok(())
+    }
+    pub fn end(&mut self) -> Result<()> {
+        assert!(self.in_txn);
+        self.conn.wal_insert_end()?;
+        self.in_txn = false;
+        Ok(())
+    }
+    pub fn in_txn(&self) -> bool {
+        self.in_txn
+    }
+}
+
+impl<'a> Drop for WalSession<'a> {
+    fn drop(&mut self) {
+        if self.in_txn {
+            let _ = self
+                .end()
+                .inspect_err(|e| tracing::error!("failed to close WAL session: {}", e));
+        }
+    }
+}