`langchain_community.chat_message_histories.cassandra`.CassandraChatMessageHistory¶

class langchain_community.chat_message_histories.cassandra.CassandraChatMessageHistory(session_id: str, session: Optional[Session] = None, keyspace: Optional[str] = None, table_name: str = 'message_store', ttl_seconds: Optional[int] = None, *, setup_mode: SetupMode = SetupMode.SYNC)[source]¶

Chat message history that is backed by Cassandra.

Initialize a new instance of CassandraChatMessageHistory.

Parameters

session_id (str) – arbitrary key that is used to store the messages of a single chat session.
session (Optional[Session]) – Cassandra driver session. If not provided, it is resolved from cassio.
keyspace (Optional[str]) – Cassandra key space. If not provided, it is resolved from cassio.
table_name (str) – name of the table to use.
ttl_seconds (Optional[int]) – time-to-live (seconds) for automatic expiration of stored entries. None (default) for no expiration.
setup_mode (SetupMode) – mode used to create the Cassandra table (SYNC, ASYNC or OFF).

Attributes

messages

Retrieve all session messages from DB

Methods

`__init__`(session_id[, session, keyspace, ...])	Initialize a new instance of CassandraChatMessageHistory.
`aadd_messages`(messages)	Async add a list of messages.
`aclear`()	Clear session memory from DB
`add_ai_message`(message)	Convenience method for adding an AI message string to the store.
`add_message`(message)	Write a message to the table
`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`()	Retrieve all session messages from DB
`clear`()	Clear session memory from DB

__init__(session_id: str, session: Optional[Session] = None, keyspace: Optional[str] = None, table_name: str = 'message_store', ttl_seconds: Optional[int] = None, *, setup_mode: SetupMode = SetupMode.SYNC) → None[source]¶

Initialize a new instance of CassandraChatMessageHistory.

Parameters

session_id (str) – arbitrary key that is used to store the messages of a single chat session.
session (Optional[Session]) – Cassandra driver session. If not provided, it is resolved from cassio.
keyspace (Optional[str]) – Cassandra key space. If not provided, it is resolved from cassio.
table_name (str) – name of the table to use.
ttl_seconds (Optional[int]) – time-to-live (seconds) for automatic expiration of stored entries. None (default) for no expiration.
setup_mode (SetupMode) – mode used to create the Cassandra table (SYNC, ASYNC or OFF).

Return type

None

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

Async add a list of messages.

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

async aclear() → None[source]¶

Clear session memory from DB

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]¶

Write a message to the table

Parameters: message (BaseMessage) – A message to write.
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][source]¶

Retrieve all session messages from DB

Return type: List[BaseMessage]

clear() → None[source]¶

Clear session memory from DB

Return type: None

Examples using CassandraChatMessageHistory¶

langchain_community.chat_message_histories.cassandra.CassandraChatMessageHistory¶

Examples using CassandraChatMessageHistory¶

`langchain_community.chat_message_histories.cassandra`.CassandraChatMessageHistory¶