Adding Redis Memory Support (langchain-ai#951)

* Merge post upstream sync (#1)

* Added RedisMemory with tests and docs

* fixed Redis test file name

* TODOs for quick refactor

* updated memory to accept a client

* Added TODOS

* ongoing testing

* Updated tests

* Updated tests for memory return option

* finalized tests + updated docs

* Adding docs

* Readded init and cleaned up func

* fixed test typing

* redo yarn lock

* remove yarn.lock

* updated yarn lock and namespaced redis

* fix merge conflict

* updated BaseChatMemoryInput

* Updated with lint fixes

* Fixed docs to match memory instantiation

* yarn format docs

* Merging fixes to address ForkPR comments (langchain-ai#2)

* updating for pr

* Removed redis_memory in favor of chat memory

* Fixed tests and updated docs

* Bump docs

* lint results

* fixes from lint and format

---------

Co-authored-by: Chris Toomey <[email protected]>

* Update RedisChatMessageHistory class to initialize a client internally

* Update Redis chat message history docs to reflect the fact that Redis is a peer dependency, allow direct passing of Redis client

* Patch typing issues with passing node-redis client directly into a RedisChatMessageHistory instance

---------

Co-authored-by: Chris Toomey <[email protected]>
Co-authored-by: Jacob Lee <[email protected]>

docs/docs/modules/memory/examples/dynamodb.mdx

@@ -16,7 +16,7 @@ First, install the AWS DynamoDB client in your project:
 npm install @aws-sdk/client-dynamodb
 ```
 
-Next, sign into your AWS account and create a DynamoDB table. Name the table `langchain`, and name your partition key `id` and make sure it's a string. You can leave sort key and the other settings alone.
+Next, sign into your AWS account and create a DynamoDB table. Name the table `langchain`, and name your partition key `id`. Make sure your partition key is a string. You can leave sort key and the other settings alone.
 
 You'll also need to retrieve an AWS access key and secret key for a role or user that has access to the table and add them to your environment variables.
 

docs/docs/modules/memory/examples/redis.mdx

@@ -0,0 +1,36 @@
+---
+hide_table_of_contents: true
+---
+
+import CodeBlock from "@theme/CodeBlock";
+
+# Redis-Backed Chat Memory
+
+For longer-term persistence across chat sessions, you can swap out the default in-memory `chatHistory` that backs chat memory classes like `BufferMemory` for a [Redis](https://redis.io/) instance.
+
+## Setup
+
+You will need to install [node-redis](https://github.com/redis/node-redis) in your project:
+
+```bash npm2yarn
+npm install redis
+```
+
+You will also need a Redis instance to connect to. See instructions on [the official Redis website](https://redis.io/docs/getting-started/) for running the server locally.
+
+## Usage
+
+Each chat history session stored in Redis must have a unique id. You can provide an optional `sessionTTL` to make sessions expire after a give number of seconds.
+The `config` parameter is passed directly into the `createClient` method of [node-redis](https://github.com/redis/node-redis), and takes all the same arguments.
+
+import Example from "@examples/memory/redis.ts";
+
+<CodeBlock language="typescript">{Example}</CodeBlock>
+
+## Advanced Usage
+
+You can also directly pass in a previously created [node-redis](https://github.com/redis/node-redis) client instance:
+
+import AdvancedExample from "@examples/memory/redis-advanced.ts";
+
+<CodeBlock language="typescript">{AdvancedExample}</CodeBlock>

docs/docs/modules/memory/examples/vector_store_memory.mdx

@@ -5,7 +5,7 @@ hide_table_of_contents: true
 import CodeBlock from "@theme/CodeBlock";
 import Example from "@examples/memory/vector_store.ts";
 
-# VectorStore-backed Memory
+# VectorStore-Backed Memory
 
 `VectorStoreRetrieverMemory` stores memories in a VectorDB and queries the top-K most "salient" docs every time it is called.
 

examples/package.json

@@ -38,6 +38,7 @@
     "ml-distance": "^4.0.0",
     "mongodb": "^5.2.0",
     "prisma": "^4.11.0",
+    "redis": "^4.6.6",
     "sqlite3": "^5.1.4",
     "typeorm": "^0.3.12",
     "weaviate-ts-client": "^1.0.0",

examples/src/memory/redis-advanced.ts

@@ -0,0 +1,45 @@
+import { createClient } from "redis";
+import { BufferMemory } from "langchain/memory";
+import { RedisChatMessageHistory } from "langchain/stores/message/redis";
+import { ChatOpenAI } from "langchain/chat_models/openai";
+import { ConversationChain } from "langchain/chains";
+
+const client = createClient({
+  url: "redis://localhost:6379",
+});
+
+const memory = new BufferMemory({
+  chatHistory: new RedisChatMessageHistory({
+    sessionId: new Date().toISOString(),
+    sessionTTL: 300,
+    client,
+  }),
+});
+
+const model = new ChatOpenAI({
+  modelName: "gpt-3.5-turbo",
+  temperature: 0,
+});
+
+const chain = new ConversationChain({ llm: model, memory });
+
+const res1 = await chain.call({ input: "Hi! I'm Jim." });
+console.log({ res1 });
+/*
+{
+  res1: {
+    text: "Hello Jim! It's nice to meet you. My name is AI. How may I assist you today?"
+  }
+}
+*/
+
+const res2 = await chain.call({ input: "What did I just say my name was?" });
+console.log({ res2 });
+
+/*
+{
+  res1: {
+    text: "You said your name was Jim."
+  }
+}
+*/

examples/src/memory/redis.ts

@@ -0,0 +1,42 @@
+import { BufferMemory } from "langchain/memory";
+import { RedisChatMessageHistory } from "langchain/stores/message/redis";
+import { ChatOpenAI } from "langchain/chat_models/openai";
+import { ConversationChain } from "langchain/chains";
+
+const memory = new BufferMemory({
+  chatHistory: new RedisChatMessageHistory({
+    sessionId: new Date().toISOString(), // Or some other unique identifier for the conversation
+    sessionTTL: 300, // 5 minutes, omit this parameter to make sessions never expire
+    config: {
+      url: "redis://localhost:6379", // Default value, override with your own instance's URL
+    },
+  }),
+});
+
+const model = new ChatOpenAI({
+  modelName: "gpt-3.5-turbo",
+  temperature: 0,
+});
+
+const chain = new ConversationChain({ llm: model, memory });
+
+const res1 = await chain.call({ input: "Hi! I'm Jim." });
+console.log({ res1 });
+/*
+{
+  res1: {
+    text: "Hello Jim! It's nice to meet you. My name is AI. How may I assist you today?"
+  }
+}
+*/
+
+const res2 = await chain.call({ input: "What did I just say my name was?" });
+console.log({ res2 });
+
+/*
+{
+  res1: {
+    text: "You said your name was Jim."
+  }
+}
+*/

langchain/.gitignore

@@ -265,6 +265,9 @@ stores/file/node.d.ts
 stores/message/dynamodb.cjs
 stores/message/dynamodb.js
 stores/message/dynamodb.d.ts
+stores/message/redis.cjs
+stores/message/redis.js
+stores/message/redis.d.ts
 experimental/autogpt.cjs
 experimental/autogpt.js
 experimental/autogpt.d.ts

langchain/package.json

@@ -277,6 +277,9 @@
     "stores/message/dynamodb.cjs",
     "stores/message/dynamodb.js",
     "stores/message/dynamodb.d.ts",
+    "stores/message/redis.cjs",
+    "stores/message/redis.js",
+    "stores/message/redis.d.ts",
     "experimental/autogpt.cjs",
     "experimental/autogpt.js",
     "experimental/autogpt.d.ts",
@@ -1007,6 +1010,11 @@
       "import": "./stores/message/dynamodb.js",
       "require": "./stores/message/dynamodb.cjs"
     },
+    "./stores/message/redis": {
+      "types": "./stores/message/redis.d.ts",
+      "import": "./stores/message/redis.js",
+      "require": "./stores/message/redis.cjs"
+    },
     "./experimental/autogpt": {
       "types": "./experimental/autogpt.d.ts",
       "import": "./experimental/autogpt.js",

langchain/scripts/create-entrypoints.js

@@ -119,6 +119,7 @@ const entrypoints = {
   "stores/file/in_memory": "stores/file/in_memory",
   "stores/file/node": "stores/file/node",
   "stores/message/dynamodb": "stores/message/dynamodb",
+  "stores/message/redis": "stores/message/redis",
   // experimental
   "experimental/autogpt": "experimental/autogpt/index",
   "experimental/babyagi": "experimental/babyagi/index",
@@ -191,6 +192,7 @@ const requiresOptionalDependency = [
   "cache/redis",
   "stores/file/node",
   "stores/message/dynamodb",
+  "stores/message/redis",
 ];
 
 // List of test-exports-* packages which we use to test that the exports field

langchain/src/stores/message/redis.ts

@@ -0,0 +1,85 @@
+import {
+  createClient,
+  RedisClientOptions,
+  RedisClientType,
+  RedisModules,
+  RedisFunctions,
+  RedisScripts,
+} from "redis";
+import {
+  BaseChatMessage,
+  BaseListChatMessageHistory,
+} from "../../schema/index.js";
+import {
+  StoredMessage,
+  mapChatMessagesToStoredMessages,
+  mapStoredMessagesToChatMessages,
+} from "./utils.js";
+
+export type RedisChatMessageHistoryInput = {
+  sessionId: string;
+  sessionTTL?: number;
+  config?: RedisClientOptions;
+  // Typing issues with createClient output: https://github.com/redis/node-redis/issues/1865
+  // eslint-disable-next-line @typescript-eslint/no-explicit-any
+  client?: any;
+};
+
+export class RedisChatMessageHistory extends BaseListChatMessageHistory {
+  public client: RedisClientType<RedisModules, RedisFunctions, RedisScripts>;
+
+  private sessionId: string;
+
+  private sessionTTL?: number;
+
+  constructor(fields: RedisChatMessageHistoryInput) {
+    const { sessionId, sessionTTL, config, client } = fields;
+    super();
+    this.client = (client ?? createClient(config ?? {})) as RedisClientType<
+      RedisModules,
+      RedisFunctions,
+      RedisScripts
+    >;
+    this.sessionId = sessionId;
+    this.sessionTTL = sessionTTL;
+  }
+
+  async ensureReadiness() {
+    if (!this.client.isReady) {
+      await this.client.connect();
+    }
+    return true;
+  }
+
+  async getMessages(): Promise<BaseChatMessage[]> {
+    await this.ensureReadiness();
+    const rawStoredMessages = await this.client.lRange(this.sessionId, 0, -1);
+    const orderedMessages = rawStoredMessages
+      .reverse()
+      .map((message) => JSON.parse(message));
+    const previousMessages = orderedMessages
+      .map((item) => ({
+        type: item.type,
+        role: item.role,
+        text: item.text,
+      }))
+      .filter(
+        (x): x is StoredMessage => x.type !== undefined && x.text !== undefined
+      );
+    return mapStoredMessagesToChatMessages(previousMessages);
+  }
+
+  async addMessage(message: BaseChatMessage): Promise<void> {
+    await this.ensureReadiness();
+    const messageToAdd = mapChatMessagesToStoredMessages([message]);
+    await this.client.lPush(this.sessionId, JSON.stringify(messageToAdd[0]));
+    if (this.sessionTTL) {
+      await this.client.expire(this.sessionId, this.sessionTTL);
+    }
+  }
+
+  async clear(): Promise<void> {
+    await this.ensureReadiness();
+    await this.client.del(this.sessionId);
+  }
+}