langchain_community.chat_message_histories.postgres.PostgresChatMessageHistory¶

class langchain_community.chat_message_histories.postgres.PostgresChatMessageHistory(session_id: str, connection_string: str = 'postgresql://postgres:mypassword@localhost/chat_history', table_name: str = 'message_store')[source]¶

[Deprecated] Chat message history stored in a Postgres database.

DEPRECATED: This class is deprecated and will be removed in a future version.

Use the PostgresChatMessageHistory implementation in langchain_postgres.

Notes

Deprecated since version 0.0.31: This class is deprecated and will be removed in a future version. You can swap to using the PostgresChatMessageHistory implementation in langchain_postgres. Please do not submit further PRs to this class.See https://github.com/langchain-ai/langchain-postgres Use from langchain_postgres import PostgresChatMessageHistory; instead.

Attributes

messages

Retrieve the messages from PostgreSQL

Methods

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

aadd_messages(messages)

Add a list of messages.

aclear()

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 PostgreSQL

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 PostgreSQL
Parameters

  • session_id (str) –

  • connection_string (str) –

  • table_name (str) –

__init__(session_id: str, connection_string: str = 'postgresql://postgres:mypassword@localhost/chat_history', table_name: str = 'message_store')[source]¶
Parameters

  • session_id (str) –

  • connection_string (str) –

  • table_name (str) –

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

Add a list of messages.

Parameters

messages (Sequence[BaseMessage]) – A list of BaseMessage objects to store.

Return type

None

async aclear() → None¶

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 PostgreSQL

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 list 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

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 PostgreSQL

Return type

None

Examples using PostgresChatMessageHistory¶