CockroachDB 聊天消息历史

pip install -qU langchain-cockroachdb

# CockroachDB Cloud
CONNECTION_STRING = "cockroachdb://user:password@host:26257/database?sslmode=verify-full"

# 本地非安全集群
CONNECTION_STRING = "cockroachdb://root@localhost:26257/defaultdb?sslmode=disable"

import asyncio
from langchain_cockroachdb import CockroachDBChatMessageHistory

# 创建表（只需执行一次）
async def setup():
    chat_history = CockroachDBChatMessageHistory(
        session_id="setup",
        connection_string=CONNECTION_STRING,
        table_name="chat_history",
    )
    await chat_history._acreate_table_if_not_exists()

asyncio.run(setup())

import uuid

session_id = str(uuid.uuid4())  # 此对话的唯一 ID

chat_history = CockroachDBChatMessageHistory(
    session_id=session_id,
    connection_string=CONNECTION_STRING,
    table_name="chat_history",
)

from langchain.messages import HumanMessage, AIMessage

# 向对话添加消息
await chat_history.aadd_message(HumanMessage(content="你好！什么是 CockroachDB？"))
await chat_history.aadd_message(AIMessage(content="CockroachDB 是一个分布式 SQL 数据库..."))

messages = [
    HumanMessage(content="什么是向量索引？"),
    AIMessage(content="向量索引支持快速相似性搜索..."),
    HumanMessage(content="它们如何工作？"),
    AIMessage(content="它们使用近似最近邻算法..."),
]

await chat_history.aadd_messages(messages)

messages = await chat_history.aget_messages()

for msg in messages:
    if isinstance(msg, HumanMessage):
        print(f"用户：{msg.content}")
    elif isinstance(msg, AIMessage):
        print(f"AI：{msg.content}")

await chat_history.aclear()

# 同步用法
chat_history_sync = CockroachDBChatMessageHistory(
    session_id=session_id,
    connection_string=CONNECTION_STRING,
    table_name="chat_history",
)

# 同步操作
chat_history_sync.add_message(HumanMessage(content="你好！"))
messages = chat_history_sync.messages
chat_history_sync.clear()