# Proxy with Astro

> Serve the MetricRaven script and events from an Astro server endpoint.

Source: https://metricraven.com/docs/proxy-astro  
Markdown: https://metricraven.com/docs/proxy-astro.md  
Section: Proxy

An on-demand Astro endpoint relays the script and events. It needs a server adapter.

## Set it up

1. **Make sure your project has an adapter**

   Server endpoints run only with an adapter such as `@astrojs/node`, `@astrojs/vercel`, `@astrojs/netlify` or `@astrojs/cloudflare`. Add one with `npx astro add node` (or your host's name). Fully static sites: use your host's recipe instead (see the notes).

2. **Add the endpoint**

   ```typescript title="src/pages/a/[kind].ts"
   // src/pages/a/[kind].ts · needs an Astro adapter (Node, Vercel, Netlify or Cloudflare)
   import type { APIRoute } from "astro";

   export const prerender = false;

   export const ALL: APIRoute = async ({ params, request, clientAddress }) => {
     const script = params.kind === "script" && request.method === "GET";
     const event = params.kind === "event" && request.method === "POST";
     if (!script && !event) return new Response("Not found", { status: 404 });
     const headers = new Headers({ "x-visitor-ip": clientAddress });
     for (const name of ["content-type", "origin", "user-agent"]) {
       const value = request.headers.get(name);
       if (value) headers.set(name, value);
     }
     const upstream = await fetch(script ? "https://metricraven.com/js/script.js" : "https://metricraven.com/api/v1/collect", {
       method: request.method,
       headers,
       body: event ? await request.arrayBuffer() : undefined,
       signal: AbortSignal.timeout(15000),
     });
     return new Response(upstream.body, {
       status: upstream.status,
       headers: {
         "Content-Type": upstream.headers.get("content-type") || "application/octet-stream",
         "Cache-Control": script ? "public, max-age=3600" : "no-store",
       },
     });
   };
   ```

   `clientAddress` is the visitor IP as your adapter reports it. `prerender = false` keeps this one route on demand even when the rest of the site is static.

3. **Update the tag in your base layout**

   Astro doesn't bundle a script tag that has attributes besides `src`, so the tag works as is. Adding `is:inline` makes that explicit.

4. **Point your script tag at your own paths**

   Replace your MetricRaven tag with this one. `src` loads the tracker from your domain and `data-api` sends its events there too.

   ```html title="Your website's shared layout"
   <script defer src="/a/script" data-api="/a/event" data-site-id="YOUR_SITE_ID"></script>
   ```

> **Verify it works**
>
> Open your live site. In the browser's Network panel, `/a/script` loads the tracker and `/a/event` answers with `ok: true`. Nothing goes to `metricraven.com` from the browser.
>
> In **Traffic**, your own visit should show your real country and city. If every visit appears to come from your server's or host's location, the visitor IP isn't being forwarded.

## Notes

- Static Astro builds have no server. Use the [Vercel](https://metricraven.com/docs/proxy-vercel), [Netlify](https://metricraven.com/docs/proxy-netlify) or [Cloudflare Workers](https://metricraven.com/docs/proxy-cloudflare-workers) recipe for your host.
- With the Node adapter behind a load balancer, check that `clientAddress` is the visitor and not the balancer.

How the proxy works and which headers it must send: [Use your own domain](https://metricraven.com/docs/proxy).

## Details

- The proxy forwards only `Content-Type`, `Origin`, `User-Agent` and the visitor's IP as `x-visitor-ip`. Your site's cookies and auth headers never leave your server.
- `Origin` matters: MetricRaven checks it against your site's allowed domains. A missing or wrong origin is refused with `domain_not_allowed`.
- MetricRaven allows about 120 events per minute per visitor IP. Without `x-visitor-ip`, all of your visitors share the proxy's IP, so busy sites lose events as well as locations.
- A proxy doesn't guarantee that every blocker will allow tracking.