# Fastly

<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.
</Tip>


### Database Setup

Create a Redis database using [Upstash Console](https://console.upstash.com) or
[Upstash CLI](https://github.com/upstash/cli). Select the global to minimize the
latency from all edge locations. Copy the `UPSTASH_REDIS_REST_URL` and
`UPSTASH_REDIS_REST_TOKEN` for the next steps.

### Project Setup

We will use Fastly CLI for deployment, so please install
[Fastly CLI](https://www.fastly.com/documentation/reference/cli/).

Create a folder for your project and run `fastly compute init`. Select
`[2] JavaScript`, then `[2] Empty starter for JavaScript`

```shell
> fastly compute init

Creating a new Compute project.

Press ^C at any time to quit.

Name: [fastly-upstash]
Description:
Author: [enes@upstash.com]
Language:
[1] Rust
[2] JavaScript
[3] Go
[4] Other ('bring your own' Wasm binary)
Choose option: [1] 2
Starter kit:
[1] Default starter for JavaScript
    A basic starter kit that demonstrates routing, simple synthetic responses and
    overriding caching rules.
    https://github.com/fastly/compute-starter-kit-javascript-default
[2] Empty starter for JavaScript
    An empty application template for the Fastly Compute environment which simply
    returns a 200 OK response.
    https://github.com/fastly/compute-starter-kit-javascript-empty
Choose option or paste git URL: [1] 2
```

Install @upstash/redis:

```shell
npm install @upstash/redis
```

Now, we will create a Fastly Compute service by running,
`fastly compute publish`. You need to add your Upstash database's endpoint as a
backend and select 443 as its port.

```shell
> fastly compute publish
✓ Initializing...
✓ Verifying package manifest...
✓ Verifying local javascript toolchain...
✓ Building package using javascript toolchain...
✓ Creating package archive...

SUCCESS: Built package 'fastly-upstash' (pkg/fastly-upstash.tar.gz)


There is no Fastly service associated with this package. To connect to an existing service
add the Service ID to the fastly.toml file, otherwise follow the prompts to create a
service now.

Press ^C at any time to quit.

Create new service: [y/N] y

✓ Initializing...
✓ Creating service...

Domain: [supposedly-included-corgi.edgecompute.app]

Backend (hostname or IP address, or leave blank to stop adding backends): global-concise-scorpion-30984.upstash.io
Backend port number: [80] 443
Backend name: [backend_1] upstash

Backend (hostname or IP address, or leave blank to stop adding backends):

✓ Creating domain 'supposedly-smart-corgi.edgecompute.app'...
✓ Creating backend 'upstash' (host: global-concise-scorpion-30984.upstash.io, port: 443)...
✓ Uploading package...
✓ Activating version...
```

### The Code

Update `src/index.js` as below:

```js
import { Redis } from "@upstash/redis/fastly";

addEventListener("fetch", (event) => event.respondWith(handleRequest(event)));

async function handleRequest(event) {
  const redis = new Redis({
    url: "UPSTASH_REDIS_REST_URL",
    token: "UPSTASH_REDIS_REST_TOKEN",
    backend: "upstash",
  });
  const data = await redis.incr("count");
  return new Response("View Count:" + data, { status: 200 });
}
```

Hardcoded credentials are fine for this quickstart, but in production store them
in a
[Fastly Secret Store](https://www.fastly.com/documentation/guides/compute/edge-data-storage/working-with-secret-stores/)
instead.

### Deploy

Deploy: `fastly compute deploy`

After deployment, the CLI logs the endpoint. You can check the logs with:
`fastly log-tail --service-id=<YOUR_FASTLY_SERVICE_ID>`

### Run Locally

To run the function locally add the backend to your `fastly.toml` as below:

```toml
[local_server.backends.upstash]
url = "UPSTASH_REDIS_REST_URL"
```

Then run: `fastly compute serve`