GKE (Google Kubernetes Engine) does not offer an out-of-the-box HTTPS solution or TLS/SSL certificates for your websites today:

• Let’s Encrypt is a non-profit Certificate Authority that provides free TLS/SSL certificates that can be used to secure websites with HTTPS.
• cert-manager is a third-party Kubernetes controller that automates getting TLS/SSL certificates from Let’s Encrypt and refreshing them.

⚠️⚠️ cert-manager is pre-stable software and is not officially supported by Google. Use it at your own risk! ⚠️⚠️

Requirements:

• A registered domain name
• A GKE cluster
• Estimated time: 30 minutes.

1. Install Helm
2. Install cert-manager
3. Set up Let's Encrypt
4. Deploy a web app on a domain name
5. Get a certificate for your domain
6. Start serving HTTPS with the certificate
7. Cleanup

• Redirecting HTTP traffic to HTTPS (not possible with GKE Ingress yet)
• Securing traffic between Cloud Load Balancer and your app with TLS

If you're looking for a far simpler third-party solution and you're OK with HTTPS requests from your visitors terminated/proxied by a third-party, these services work with GKE apps:

• Cloudflare (has a free tier)
• Backplane

This is not an official Google product or documentation.