Hi all!
To set some context — we’re building a platform where customers can bring their own domains, with support for up to 5 domains per customer. We guide customers through the configuration steps via our live UI, which they need to complete with their domain registrars/DNS providers. We then check for DNS records using public DoH (DNS over HTTPS) services every minute to verify that the DNS records match (including an additional TXT record for ownership verification).
We perform this check via DoH before triggering Fly.io’s verification API to maximize the chances of success, as Let’s Encrypt has rate limits on verifications. We may continue refreshing the status every minute to display verification and certificate status updates.
I’ve tried to account for any rate limits on the Fly.io GraphQL API but couldn’t find any documented. Are there any rate limits? And is this approach reasonable?
We might need to query fly certs check hostname for up to 5 * hostnames * active users concurrently with a single auth token via GraphQL.
The experience would be similar to Vercel’s custom domain management page.