Connect a custom domain to an Aiven App Limited availability

Connect a custom domain to an Aiven App using Cloudflare as a proxied reverse proxy. Cloudflare receives traffic for the custom domain and forwards it to the Aiven-generated app hostname.

Prerequisites

An Aiven App with a publicly accessible URL.
A domain that is managed by Cloudflare and uses Cloudflare nameservers.

Connect a custom domain managed by Cloudflare

To get the Aiven App URL, in the Aiven Console, click Applications and open your app.
In the Connection information section, copy the Application URL.
In Cloudflare, open your domain and click DNS Records.
Click Add Record.
For the Type, select CNAME.
Enter the Name.
For the Target, enter the Aiven App URL without https://.
Set the Proxy status to Proxied, and TTL to Auto.
Click Back to Domains, and in the sidebar, click Compute > Workers & Pages.
Click Create application > Worker. You can also use an existing Worker or deploy with Wrangler.

Configure the Worker. The following example forwards requests to an Aiven App host while preserving the original request method, body, and headers:

const AIVEN_HOST = "AIVEN_APP_HOSTNAME";

export default {
  async fetch(request, env, ctx) {
    const incomingUrl = new URL(request.url);
    const upstreamUrl = new URL(request.url);

    upstreamUrl.protocol = "https:";
    upstreamUrl.hostname = AIVEN_HOST;
    upstreamUrl.port = "";

    const headers = new Headers(request.headers);

    headers.delete("Host");
    headers.set("X-Forwarded-Host", incomingUrl.host);
    headers.set("X-Forwarded-Proto", "https");

    const init = {
      method: request.method,
      headers,
      redirect: "manual",
    };

    if (request.method !== "GET" && request.method !== "HEAD") {
      init.body = request.body;
    }

    const response = await fetch(upstreamUrl.toString(), init);
    const responseHeaders = new Headers(response.headers);

    rewriteLocationHeader(responseHeaders, incomingUrl);

    return new Response(response.body, {
      status: response.status,
      statusText: response.statusText,
      headers: responseHeaders,
    });
  },
};

function rewriteLocationHeader(headers, incomingUrl) {
  const location = headers.get("Location");

  if (!location) {
    return;
  }

  const publicOrigin = `${incomingUrl.protocol}//${incomingUrl.host}`;
  const upstreamOrigin = `https://${AIVEN_HOST}`;

  if (location.startsWith(upstreamOrigin)) {
    headers.set("Location", location.replace(upstreamOrigin, publicOrigin));
  }
}

Click Deploy.
Open your domain and click Workers Routes.
Click Add route.
Add the Route using the pattern that matches the hostname you configured:
- Root domain: example.com/*
- www subdomain: www.example.com/*
- Other subdomain: app.example.com/*
Select the Worker and click Save.
Go to SSL/TLS and verify the SSL/TLS mode. To ensure Cloudflare connects to the Aiven App origin over HTTPS, set the mode to Full (strict).
Open the custom domain in a browser to confirm the app loads.

Prerequisites​

Connect a custom domain managed by Cloudflare​

Prerequisites

Connect a custom domain managed by Cloudflare