Fix: MySQL Driver error: Transactions couldn't be nested (#1271)

Author: mdecimus

crates/store/src/backend/mysql/write.rs

@@ -37,23 +37,29 @@ impl MysqlStore {
         let mut conn = self.conn_pool.get_conn().await.map_err(into_error)?;
 
         loop {
-            match self.write_trx(&mut conn, &batch).await {
+            let err = match self.write_trx(&mut conn, &batch).await {
                 Ok(result) => {
                     return Ok(result);
                 }
-                Err(CommitError::Mysql(Error::Server(err)))
+                Err(err) => err,
+            };
+
+            let _ = conn.query_drop("ROLLBACK;").await;
+
+            match err {
+                CommitError::Mysql(Error::Server(err))
                     if [1062, 1213].contains(&err.code)
                         && retry_count < MAX_COMMIT_ATTEMPTS
                         && start.elapsed() < MAX_COMMIT_TIME => {}
-                Err(CommitError::Retry) => {
+                CommitError::Retry => {
                     if retry_count > MAX_COMMIT_ATTEMPTS || start.elapsed() > MAX_COMMIT_TIME {
                         return Err(trc::StoreEvent::AssertValueFailed.into());
                     }
                 }
-                Err(CommitError::Mysql(err)) => {
+                CommitError::Mysql(err) => {
                     return Err(into_error(err));
                 }
-                Err(CommitError::Internal(err)) => {
+                CommitError::Internal(err) => {
                     return Err(err);
                 }
             }
@@ -318,13 +324,7 @@ impl MysqlStore {
             }
         }
 
-        match trx.commit().await {
-            Ok(_) => Ok(result),
-            Err(err) => {
-                let _ = conn.query_drop("ROLLBACK;").await;
-                Err(err.into())
-            }
-        }
+        trx.commit().await.map(|_| result).map_err(Into::into)
     }
 
     pub(crate) async fn purge_store(&self) -> trc::Result<()> {