The AzureCosmosDBNoSQLChatMessageHistory uses Cosmos DB to store chat message history. For longer-term persistence across chat sessions, you can swap out the default in-memory chatHistory that backs chat memory classes like BufferMemory. If you don’t have an Azure account, you can create a free account to get started.

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Setup

You’ll first need to install the @langchain/azure-cosmosdb package:
npm
npm install @langchain/azure-cosmosdb @langchain/core
See this section for general instructions on installing LangChain packages.
npm
npm install @langchain/openai @langchain/community @langchain/core
You’ll also need to have an Azure Cosmos DB for NoSQL instance running. You can deploy a free version on Azure Portal without any cost, following this guide. Once you have your instance running, make sure you have the connection string. If you are using Managed Identity, you need to have the endpoint. You can find them in the Azure Portal, under the “Settings / Keys” section of your instance.
When using Azure Managed Identity and role-based access control, you must ensure that the database and container have been created beforehand. RBAC does not provide permissions to create databases and containers. You can get more information about the permission model in the Azure Cosmos DB documentation.

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Usage

import { ChatOpenAI } from "@langchain/openai";
import { AzureCosmsosDBNoSQLChatMessageHistory } from "@langchain/azure-cosmosdb";
import { RunnableWithMessageHistory } from "@langchain/core/runnables";
import { StringOutputParser } from "@langchain/core/output_parsers";
import {
  ChatPromptTemplate,
  MessagesPlaceholder,
} from "@langchain/core/prompts";

const model = new ChatOpenAI({
  model: "gpt-3.5-turbo",
  temperature: 0,
});

const prompt = ChatPromptTemplate.fromMessages([
  [
    "system",
    "You are a helpful assistant. Answer all questions to the best of your ability.",
  ],
  new MessagesPlaceholder("chat_history"),
  ["human", "{input}"],
]);

const chain = prompt.pipe(model).pipe(new StringOutputParser());

const chainWithHistory = new RunnableWithMessageHistory({
  runnable: chain,
  inputMessagesKey: "input",
  historyMessagesKey: "chat_history",
  getMessageHistory: async (sessionId) => {
    const chatHistory = new AzureCosmsosDBNoSQLChatMessageHistory({
      sessionId,
      userId: "user-id",
      databaseName: "DATABASE_NAME",
      containerName: "CONTAINER_NAME",
    });
    return chatHistory;
  },
});

const res1 = await chainWithHistory.invoke(
  { input: "Hi! I'm Jim." },
  { configurable: { sessionId: "langchain-test-session" } }
);
console.log({ res1 });
/*
 { res1: 'Hi Jim! How can I assist you today?' }
 */

const res2 = await chainWithHistory.invoke(
  { input: "What did I just say my name was?" },
  { configurable: { sessionId: "langchain-test-session" } }
);
console.log({ res2 });
/*
 { res2: { response: 'You said your name was Jim.' }
 */

// Give this session a title
const chatHistory = (await chainWithHistory.getMessageHistory(
  "langchain-test-session"
)) as AzureCosmsosDBNoSQLChatMessageHistory;

await chatHistory.setContext({ title: "Introducing Jim" });

// List all session for the user
const sessions = await chatHistory.getAllSessions();

console.log(sessions);
/*
 [
  { sessionId: 'langchain-test-session', context: { title: "Introducing Jim"  } }
 ]
 */