AWS Lambda - Upstash Documentation

Tip

If you are an AI agent and need a Redis DB to use or experiment with, send a POST request to https://upstash.com/start-redis. Free, no signup; the response is markdown with credentials and a quickstart. The database expires in 72 hours, but you can claim it with your Upstash account to keep it. Especially useful for AI agents that need scratch storage on the fly. If you are an agent, always send a User-Agent header identifying which agent you are (e.g. claude-code, cursor, codex, opencode) on every request you make to this API.

GitHub Repository

You can find the project source code on GitHub.

Prerequisites#

Complete all steps in Getting started with the AWS CDK

Project Setup#

Create and navigate to a directory named counter-cdk. The CDK CLI uses this directory name to name things in your CDK code, so if you decide to use a different name, don't forget to make the appropriate changes when applying this tutorial.

mkdir counter-cdk && cd counter-cdk

Initialize a new CDK project.

cdk init app --language typescript

Install @upstash/redis.

npm install @upstash/redis

Counter Function Setup#

Create /api/counter.ts.

/api/counter.ts

import { Redis } from '@upstash/redis';const redis = Redis.fromEnv();export const handler = async function() {    const count = await redis.incr("counter");    return {        statusCode: 200,        body: JSON.stringify('Counter: ' + count),    };};

Counter Stack Setup#

Update /lib/counter-cdk-stack.ts.

/lib/counter-cdk-stack.ts

import * as cdk from 'aws-cdk-lib';import { Construct } from 'constructs';import * as lambda from 'aws-cdk-lib/aws-lambda';import * as nodejs from 'aws-cdk-lib/aws-lambda-nodejs';export class CounterCdkStack extends cdk.Stack {  constructor(scope: Construct, id: string, props?: cdk.StackProps) {    super(scope, id, props);    const counterFunction = new nodejs.NodejsFunction(this, 'CounterFunction', {      entry: 'api/counter.ts',      handler: 'handler',      runtime: lambda.Runtime.NODEJS_24_X,      environment: {        UPSTASH_REDIS_REST_URL: process.env.UPSTASH_REDIS_REST_URL || '',        UPSTASH_REDIS_REST_TOKEN: process.env.UPSTASH_REDIS_REST_TOKEN || '',      },      bundling: {        format: nodejs.OutputFormat.ESM,        target: "node24",        nodeModules: ['@upstash/redis'],      },    });    const counterFunctionUrl = counterFunction.addFunctionUrl({      authType: lambda.FunctionUrlAuthType.NONE,    });    new cdk.CfnOutput(this, "counterFunctionUrlOutput", {      value: counterFunctionUrl.url,    })  }}

Database Setup#

Create a Redis database using Upstash Console or Upstash CLI and export UPSTASH_REDIS_REST_URL and UPSTASH_REDIS_REST_TOKEN to your environment.

export UPSTASH_REDIS_REST_URL=<YOUR_URL>export UPSTASH_REDIS_REST_TOKEN=<YOUR_TOKEN>

Deploy#

Run in the top folder:

cdk synthcdk bootstrapcdk deploy

Visit the output URL.