fix: transactional sql migration

conversations/src/storage/db.rs

@@ -25,8 +25,8 @@ impl ChatStorage {
     }
 
     /// Applies all migrations and returns the storage instance.
-    fn run_migrations(db: SqliteDb) -> Result<Self, StorageError> {
+    fn run_migrations(mut db: SqliteDb) -> Result<Self, StorageError> {
-        migrations::apply_migrations(db.connection())?;
+        migrations::apply_migrations(db.connection_mut())?;
         Ok(Self { db })
     }
 

conversations/src/storage/migrations.rs

@@ -1,6 +1,7 @@
 //! Database migrations module.
 //!
 //! SQL migrations are embedded at compile time and applied in order.
+//! Each migration is applied atomically within a transaction.
 
 use storage::{Connection, StorageError};
 
@@ -13,8 +14,9 @@ pub fn get_migrations() -> Vec<(&'static str, &'static str)> {
 }
 
 /// Applies all migrations to the database.
+///
 /// Uses a simple version tracking table to avoid re-running migrations.
-pub fn apply_migrations(conn: &Connection) -> Result<(), StorageError> {
+pub fn apply_migrations(conn: &mut Connection) -> Result<(), StorageError> {
     // Create migrations tracking table if it doesn't exist
     conn.execute_batch(
         "CREATE TABLE IF NOT EXISTS _migrations (
@@ -32,11 +34,11 @@ pub fn apply_migrations(conn: &Connection) -> Result<(), StorageError> {
         )?;
 
         if !already_applied {
-            // Apply migration
+            // Apply migration and record it atomically in a transaction
-            conn.execute_batch(sql)?;
+            let tx = conn.transaction()?;
-
+            tx.execute_batch(sql)?;
-            // Record migration
+            tx.execute("INSERT INTO _migrations (name) VALUES (?1)", [name])?;
-            conn.execute("INSERT INTO _migrations (name) VALUES (?1)", [name])?;
+            tx.commit()?;
         }
     }
 

storage/src/sqlite.rs

@@ -66,6 +66,13 @@ impl SqliteDb {
         &self.conn
     }
 
+    /// Returns a mutable reference to the underlying connection.
+    ///
+    /// Use this for operations that require mutable access, such as transactions.
+    pub fn connection_mut(&mut self) -> &mut Connection {
+        &mut self.conn
+    }
+
     /// Begins a transaction.
     pub fn transaction(&mut self) -> Result<rusqlite::Transaction<'_>, StorageError> {
         Ok(self.conn.transaction()?)