# Ingress and the Gateway API — Kubernetes

Source: https://www.skillbyai.com/en/kubernetes/n-ingress

> HTTP routing from outside the cluster.

## Hosts, paths, TLS

To expose HTTP services, an **Ingress** routes requests by host and path to Services and terminates TLS, implemented by an **ingress controller** you install (NGINX-based, Traefik, cloud controllers). The newer **Gateway API** separates infrastructure (Gateway) from application routes (HTTPRoute), supports richer traffic management (header matching, weighted splits) and is the direction the community is moving. Use cert-manager or your provider for certificates.

## An HTTPRoute splitting traffic (Gateway API)

Not applied to a live cluster in this course; check field names against the API reference for your version.

```yaml
apiVersion: gateway.networking.k8s.io/v1
kind: HTTPRoute
metadata:
  name: shop
spec:
  parentRefs: [{name: public-gateway}]
  hostnames: ["shop.example.com"]
  rules:
  - matches: [{path: {type: PathPrefix, value: /}}]
    backendRefs:
    - {name: web-stable, port: 80, weight: 90}
    - {name: web-canary, port: 80, weight: 10}
```

## Prefer the Gateway API for new setups

Check whether your platform supports it; it handles canaries and team ownership more cleanly than Ingress annotations.

**Quiz:** What must be installed for an Ingress resource to do anything?

- [ ] A database
- [ ] A second cluster
- [x] An ingress controller
- [ ] Nothing, it works by itself

*Answer:* An ingress controller. Ingress is a spec; a controller implements it.