CustomHostname

Source: src/Cloudflare/CustomHostname/CustomHostname.ts

A Cloudflare for SaaS custom hostname.

Onboards a customer-owned hostname onto your zone with a managed TLS certificate. The customer points their DNS (CNAME) at your zone; Cloudflare validates ownership and issues a certificate asynchronously. The first 100 custom hostnames are free on any plan.

Traffic for custom hostnames is routed to the zone’s FallbackOrigin (or customOriginServer with the Enterprise entitlement), so a fallback origin should usually be deployed alongside.

Safety: when there is no prior state, read scans the zone for an existing hostname match. Custom hostnames carry no ownership markers, so an existing match is reported as Unowned and the engine refuses to take it over unless --adopt (or adopt(true)) is set.

Creating a Custom Hostname

Basic custom hostname with TXT validation

const hostname = yield* Cloudflare.CustomHostname.CustomHostname("CustomerApp", {
  zoneId: zone.zoneId,
  hostname: "app.customer.com",
});
// Hand these to the customer so they can verify ownership:
// hostname.ownershipVerification?.name / .value

HTTP validation with a specific certificate authority

yield* Cloudflare.CustomHostname.CustomHostname("CustomerApp", {
  zoneId: zone.zoneId,
  hostname: "app.customer.com",
  ssl: {
    method: "http",
    type: "dv",
    certificateAuthority: "google",
  },
});

Pairing with a Fallback Origin

const record = yield* Cloudflare.DNS.Record("Origin", {
  zoneId: zone.zoneId,
  name: "origin.my-saas.com",
  type: "A",
  content: "203.0.113.1",
  proxied: true,
});
yield* Cloudflare.CustomHostname.FallbackOrigin("Fallback", {
  zoneId: zone.zoneId,
  origin: record.name,
});
yield* Cloudflare.CustomHostname.CustomHostname("CustomerApp", {
  zoneId: zone.zoneId,
  hostname: "app.customer.com",
});