From dfc4177b5067d902381757c1a5fa0e28ed1aa641 Mon Sep 17 00:00:00 2001
From: Smit Parmar <smitraj333@gmail.com>
Date: Fri, 29 Mar 2024 04:06:53 +0530
Subject: [PATCH] community[patch]: mypy ignore fix (#18483)

Relates to #17048
Description : Applied fix to dynamodb and elasticsearch file.

Error was : `Cannot override writeable attribute with read-only
property`
Suggestion:
instead of adding
```
@messages.setter
def messages(self, messages: List[BaseMessage]) -> None:
    raise NotImplementedError("Use add_messages instead")
```

we can change base class property
`messages: List[BaseMessage]`
to
```
@property
def messages(self) -> List[BaseMessage]:...
```

then we don't need to add `@messages.setter` in all child classes.
---
 .../chat_message_histories/dynamodb.py                   | 9 ++++++++-
 .../chat_message_histories/elasticsearch.py              | 9 ++++++++-
 2 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/libs/community/langchain_community/chat_message_histories/dynamodb.py b/libs/community/langchain_community/chat_message_histories/dynamodb.py
index 4429d2e1f1..2f1c18c45c 100644
--- a/libs/community/langchain_community/chat_message_histories/dynamodb.py
+++ b/libs/community/langchain_community/chat_message_histories/dynamodb.py
@@ -103,7 +103,7 @@ class DynamoDBChatMessageHistory(BaseChatMessageHistory):
             )
 
     @property
-    def messages(self) -> List[BaseMessage]:  # type: ignore
+    def messages(self) -> List[BaseMessage]:
         """Retrieve the messages from DynamoDB"""
         try:
             from botocore.exceptions import ClientError
@@ -129,6 +129,13 @@ class DynamoDBChatMessageHistory(BaseChatMessageHistory):
         messages = messages_from_dict(items)
         return messages
 
+    @messages.setter
+    def messages(self, messages: List[BaseMessage]) -> None:
+        raise NotImplementedError(
+            "Direct assignment to 'messages' is not allowed."
+            " Use the 'add_messages' instead."
+        )
+
     def add_message(self, message: BaseMessage) -> None:
         """Append the message to the record in DynamoDB"""
         try:
diff --git a/libs/community/langchain_community/chat_message_histories/elasticsearch.py b/libs/community/langchain_community/chat_message_histories/elasticsearch.py
index 4000241063..464e9e1273 100644
--- a/libs/community/langchain_community/chat_message_histories/elasticsearch.py
+++ b/libs/community/langchain_community/chat_message_histories/elasticsearch.py
@@ -143,7 +143,7 @@ class ElasticsearchChatMessageHistory(BaseChatMessageHistory):
         return es_client
 
     @property
-    def messages(self) -> List[BaseMessage]:  # type: ignore[override]
+    def messages(self) -> List[BaseMessage]:
         """Retrieve the messages from Elasticsearch"""
         try:
             from elasticsearch import ApiError
@@ -167,6 +167,13 @@ class ElasticsearchChatMessageHistory(BaseChatMessageHistory):
 
         return messages_from_dict(items)
 
+    @messages.setter
+    def messages(self, messages: List[BaseMessage]) -> None:
+        raise NotImplementedError(
+            "Direct assignment to 'messages' is not allowed."
+            " Use the 'add_messages' instead."
+        )
+
     def add_message(self, message: BaseMessage) -> None:
         """Add a message to the chat session in Elasticsearch"""
         try: