Add event lock when batch publishing events

griptape/drivers/event_listener/base_event_listener_driver.py

@@ -1,6 +1,7 @@
 from __future__ import annotations
 
 import logging
+import threading
 from abc import ABC, abstractmethod
 from typing import TYPE_CHECKING
 
@@ -18,6 +19,7 @@
 class BaseEventListenerDriver(FuturesExecutorMixin, ABC):
     batched: bool = field(default=True, kw_only=True)
     batch_size: int = field(default=10, kw_only=True)
+    thread_lock: threading.Lock = field(default=Factory(lambda: threading.Lock()))
 
     _batch: list[dict] = field(default=Factory(list), kw_only=True)
 
@@ -39,10 +41,11 @@ def _safe_try_publish_event(self, event: BaseEvent | dict, *, flush: bool) -> No
             event_payload = event if isinstance(event, dict) else event.to_dict()
 
             if self.batched:
-                self._batch.append(event_payload)
-                if len(self.batch) >= self.batch_size or flush:
-                    self.try_publish_event_payload_batch(self.batch)
-                    self._batch = []
+                with self.thread_lock:
+                    self._batch.append(event_payload)
+                    if len(self.batch) >= self.batch_size or flush:
+                        self.try_publish_event_payload_batch(self.batch)
+                        self._batch = []
                 return
             else:
                 self.try_publish_event_payload(event_payload)