`langchain_mongodb.chat_message_histories`.MongoDBChatMessageHistory¶

class langchain_mongodb.chat_message_histories.MongoDBChatMessageHistory(connection_string: str, session_id: str, database_name: str = 'chat_history', collection_name: str = 'message_store', *, session_id_key: str = 'SessionId', history_key: str = 'History', create_index: bool = True, index_kwargs: Optional[Dict] = None)[source]¶

Chat message history that stores history in MongoDB.

Setup:

Install langchain-mongodb python package.

pip install langchain-mongodb

Instantiate:

from langchain_mongodb import MongoDBChatMessageHistory


history = MongoDBChatMessageHistory(
    connection_string="mongodb://your-host:your-port/",  # mongodb://localhost:27017/
    session_id = "your-session-id",
)

Add and retrieve messages:

# Add single message
history.add_message(message)

# Add batch messages
history.add_messages([message1, message2, message3, ...])

# Add human message
history.add_user_message(human_message)

# Add ai message
history.add_ai_message(ai_message)

# Retrieve messages
messages = history.messages

Initialize with a MongoDBChatMessageHistory instance.

Parameters

connection_string (str) – str connection string to connect to MongoDB.
session_id (str) –
str arbitrary key that is used to store the messages of

a single chat session.
database_name (str) – Optional[str] name of the database to use.
collection_name (str) – Optional[str] name of the collection to use.
session_id_key (str) – Optional[str] name of the field that stores the session id.
history_key (str) – Optional[str] name of the field that stores the chat history.
create_index (bool) – Optional[bool] whether to create an index on the session id field.
index_kwargs (Optional[Dict]) – Optional[Dict] additional keyword arguments to pass to the index creation.

Attributes

messages

Retrieve the messages from MongoDB

Methods

`__init__`(connection_string, session_id[, ...])	Initialize with a MongoDBChatMessageHistory instance.
`aadd_messages`(messages)	Async add a list of messages.
`aclear`()	Async remove all messages from the store
`add_ai_message`(message)	Convenience method for adding an AI message string to the store.
`add_message`(message)	Append the message to the record in MongoDB
`add_messages`(messages)	Add a list of messages.
`add_user_message`(message)	Convenience method for adding a human message string to the store.
`aget_messages`()	Async version of getting messages.
`clear`()	Clear session memory from MongoDB

__init__(connection_string: str, session_id: str, database_name: str = 'chat_history', collection_name: str = 'message_store', *, session_id_key: str = 'SessionId', history_key: str = 'History', create_index: bool = True, index_kwargs: Optional[Dict] = None)[source]¶

Initialize with a MongoDBChatMessageHistory instance.

Parameters

connection_string (str) – str connection string to connect to MongoDB.
session_id (str) –
str arbitrary key that is used to store the messages of

a single chat session.
database_name (str) – Optional[str] name of the database to use.
collection_name (str) – Optional[str] name of the collection to use.
session_id_key (str) – Optional[str] name of the field that stores the session id.
history_key (str) – Optional[str] name of the field that stores the chat history.
create_index (bool) – Optional[bool] whether to create an index on the session id field.
index_kwargs (Optional[Dict]) – Optional[Dict] additional keyword arguments to pass to the index creation.

async aadd_messages(messages: Sequence[BaseMessage]) → None¶

Async add a list of messages.

Parameters: messages (Sequence[BaseMessage]) – A sequence of BaseMessage objects to store.
Return type: None

async aclear() → None¶

Async remove all messages from the store

Return type: None

add_ai_message(message: Union[AIMessage, str]) → None¶

Convenience method for adding an AI message string to the store.

Please note that this is a convenience method. Code should favor the bulk add_messages interface instead to save on round-trips to the underlying persistence layer.

This method may be deprecated in a future release.

Parameters: message (Union[AIMessage, str]) – The AI message to add.
Return type: None

add_message(message: BaseMessage) → None[source]¶

Append the message to the record in MongoDB

Parameters: message (BaseMessage) –
Return type: None

add_messages(messages: Sequence[BaseMessage]) → None¶

Add a list of messages.

Implementations should over-ride this method to handle bulk addition of messages in an efficient manner to avoid unnecessary round-trips to the underlying store.

Parameters: messages (Sequence[BaseMessage]) – A sequence of BaseMessage objects to store.
Return type: None

add_user_message(message: Union[HumanMessage, str]) → None¶

Convenience method for adding a human message string to the store.

Please note that this is a convenience method. Code should favor the bulk add_messages interface instead to save on round-trips to the underlying persistence layer.

This method may be deprecated in a future release.

Parameters: message (Union[HumanMessage, str]) – The human message to add to the store.
Return type: None

async aget_messages() → List[BaseMessage]¶

Async version of getting messages.

Can over-ride this method to provide an efficient async implementation.

In general, fetching messages may involve IO to the underlying persistence layer.

Return type: List[BaseMessage]

clear() → None[source]¶

Clear session memory from MongoDB

Return type: None

langchain_mongodb.chat_message_histories.MongoDBChatMessageHistory¶

`langchain_mongodb.chat_message_histories`.MongoDBChatMessageHistory¶