feat: allow users to initialize without being explicit

README.md

@@ -10,9 +10,29 @@ Features:
 - Leverages LangChain, Vercel AI SDK, and Upstash products.
 - Allows you to add various data types into your Vector store.
 
+## Installation
+
+```sh
+pnpm add @upstash/vector @uptash/index @upstash/rag-chat
+
+bun add @upstash/vector @uptash/index @upstash/rag-chat
+
+npm i @upstash/vector @uptash/index @upstash/rag-chat
+```
+
 ### Basic Usage of Initilization and `chat()`
 
-Most basic usage relies on in-memory chat history instead of Redis.
+If you are planning to use the most basic version of our SDK, make sure you have those files in your `.env`.
+
+```sh
+UPSTASH_VECTOR_REST_URL="XXXXX"
+UPSTASH_VECTOR_REST_TOKEN="XXXXX"
+
+UPSTASH_REDIS_REST_URL="XXXXX"
+UPSTASH_REDIS_REST_TOKEN="XXXXX"
+```
+
+Now, you are all set. Required Redis and Vector instances will be created for you.
 
 ```typescript
 import { ChatOpenAI } from "@langchain/openai";
@@ -26,10 +46,8 @@ const ragChat = new RAGChat({
     streaming: true,
     verbose: false,
     temperature: 0,
-    apiKey: process.env.OPENAI_API_KEY,
+    apiKey: "XXXXX",
   }),
-  vector: new Index(),
-  redis: new Redis(),
 });
 await ragchat.chat("Say Hello To My Little Friend", { stream: true });
 ```

src/config.ts

@@ -2,8 +2,8 @@ import type { BaseLanguageModelInterface } from "@langchain/core/language_models
 import type { PromptTemplate } from "@langchain/core/prompts";
 import type { RAGChatConfig } from "./types";
 import type { Ratelimit } from "@upstash/ratelimit";
-import type { Redis } from "@upstash/redis";
-import type { Index } from "@upstash/vector";
+import { Redis } from "@upstash/redis";
+import { Index } from "@upstash/vector";
 
 export class Config {
   public readonly vector: Index;
@@ -14,12 +14,25 @@ export class Config {
   public readonly prompt?: PromptTemplate;
 
   constructor(config: RAGChatConfig) {
-    this.vector = config.vector;
-    this.redis = config.redis;
+    this.vector = config.vector ?? Index.fromEnv();
+    this.redis = config.redis ?? initializeRedis();
 
     this.ratelimit = config.ratelimit;
 
     this.model = config.model;
     this.prompt = config.prompt;
   }
 }
+
+/**
+ * Attempts to create a Redis instance using environment variables.
+ * If the required environment variables are not found, it catches the error
+ * and returns undefined, allowing RAG CHAT to fall back to using an in-memory database.
+ */
+const initializeRedis = () => {
+  try {
+    return Redis.fromEnv();
+  } catch {
+    return;
+  }
+};

src/rag-chat.ts

@@ -6,10 +6,10 @@ import { QA_PROMPT_TEMPLATE } from "./prompts";
 import { UpstashModelError } from "./error/model";
 import { RatelimitUpstashError } from "./error/ratelimit";
 
-import type { Config } from "./config";
+import { Config } from "./config";
 import { RAGChatBase } from "./rag-chat-base";
 import { RateLimitService } from "./ratelimit";
-import type { ChatOptions } from "./types";
+import type { ChatOptions, RAGChatConfig } from "./types";
 import { appendDefaultsIfNeeded } from "./utils";
 import type { AddContextOptions, AddContextPayload } from "./database";
 import { Database } from "./database";
@@ -18,8 +18,8 @@ import { History } from "./history";
 export class RAGChat extends RAGChatBase {
   #ratelimitService: RateLimitService;
 
-  constructor(config: Config) {
-    const { vector: index, redis } = config;
+  constructor(config: RAGChatConfig) {
+    const { vector: index, redis } = new Config(config);
 
     const historyService = new History(redis);
     const vectorService = new Database(index);

src/types.ts

@@ -100,6 +100,6 @@ type RAGChatConfigCommon = {
 
 /**Config needed to initialize RAG Chat SDK */
 export type RAGChatConfig = {
-  vector: Index;
+  vector?: Index;
   redis?: Redis;
 } & RAGChatConfigCommon;