TiDBChatMessageHistory#

class langchain_community.chat_message_histories.tidb.TiDBChatMessageHistory(session_id: str, connection_string: str, table_name: str = 'langchain_message_store', earliest_time: datetime | None = None)[source]#

Represents a chat message history stored in a TiDB database.

Initializes a new instance of the TiDBChatMessageHistory class.

Parameters:

  • session_id (str) – The ID of the chat session.

  • connection_string (str) – The connection string for the TiDB database. format: mysql+pymysql://<host>:<PASSWORD>@<host>:4000/<db>?ssl_ca=/etc/ssl/cert.pem&ssl_verify_cert=true&ssl_verify_identity=true

  • table_name (str, optional) – the table name to store the chat messages. Defaults to “langchain_message_store”.

  • earliest_time (Optional[datetime], optional) – The earliest time to retrieve messages from. Defaults to None.

Attributes

messages

returns all messages

Methods

__init__(session_id, connection_string[, ...])

Initializes a new instance of the TiDBChatMessageHistory class.

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)

adds a message to the database and cache

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()

clears all messages

reload_cache()

reloads messages from database to cache
__init__(session_id: str, connection_string: str, table_name: str = 'langchain_message_store', earliest_time: datetime | None = None)[source]#

Initializes a new instance of the TiDBChatMessageHistory class.

Parameters:

  • session_id (str) – The ID of the chat session.

  • connection_string (str) – The connection string for the TiDB database. format: mysql+pymysql://<host>:<PASSWORD>@<host>:4000/<db>?ssl_ca=/etc/ssl/cert.pem&ssl_verify_cert=true&ssl_verify_identity=true

  • table_name (str, optional) – the table name to store the chat messages. Defaults to “langchain_message_store”.

  • earliest_time (Optional[datetime], optional) – The earliest time to retrieve messages from. Defaults to None.

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: 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]#

adds a message to the database and cache

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: 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]#

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]#

clears all messages

Return type:

None

reload_cache() → None[source]#

reloads messages from database to cache

Return type:

None

Examples using TiDBChatMessageHistory