CassandraChatMessageHistory#

class langchain_community.chat_message_histories.cassandra.CassandraChatMessageHistory(session_id: str, session: Session | None = None, keyspace: str | None = None, table_name: str = 'message_store', ttl_seconds: int | None = 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: Session | None = None, keyspace: str | None = None, table_name: str = 'message_store', ttl_seconds: int | None = 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: 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 (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: 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 (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