Add ingresses

Author: RobertoBochet

pages/21-ingresses.md

@@ -0,0 +1,123 @@
+---
+layout: two-cols
+transition: fade
+title: Ingresses
+---
+
+# [Ingresses](https://kubernetes.io/docs/concepts/services-networking/ingress/)
+
+They allow the exposure of multiple HTTP services through the same endpoint, acting as a reverse proxy
+
+<v-clicks at="7">
+
+`Ingresses` also rely on the <Link to="operator-pattern">operator pattern</Link>, but no default controller is provided out of the box
+
+<small>N.B. `Ingresses` are now in the EoL, superseded by [Gateway API](https://kubernetes.io/docs/concepts/services-networking/gateway/). However, they are still widely used</small>
+
+</v-clicks>
+
+::right::
+
+<<<@/snippets/manifests/ingresses/ingress-echo-server.yaml yaml[ingress-echo-server.yaml]{hide|all|1-2|7|10-11|12-16|all}{lines:true,at:1}
+
+<!--
+[click:2] `apiVersion` and `kind`
+
+[click] `host`
+
+[click] `path` and `pathType: Prefix`
+  - `Prefix` matches based on a URL path prefix, 
+  - `Exact` matches the URL path exactly
+
+[click] `backend`, `port` can be provided as `name` or `number`
+-->
+
+---
+layout: two-cols-header
+transition: fade
+hideInToc: true
+---
+
+# [Ingresses](https://kubernetes.io/docs/concepts/services-networking/ingress/)
+
+To use `Ingresses`, a specific controller has to provision it
+
+::left::
+
+<v-clicks>
+
+There are various controllers based on applications like `nginx`, `traefik`, etc.
+
+One of the most popular is the [Ingress-Nginx Controller](https://kubernetes.github.io/ingress-nginx/)
+
+It can be easily installed exploiting the official [helm chart](https://kubernetes.github.io/ingress-nginx/deploy/#quick-start)
+
+</v-clicks>
+
+::right::
+
+```shell{hide|all}
+helm repo add ingress-nginx \
+        https://kubernetes.github.io/ingress-nginx
+```
+
+<div class="mt-5" />
+
+<<<@/snippets/manifests/ingresses/ingress-nginx-values.yaml yaml[values.yaml]{hide|all}{lines:true}
+
+<div class="mt-5" />
+
+```shell{hide|all}
+helm install -n ingress-nginx --create-namespace \
+        --values ./values.yaml \
+        ingress-nginx ingress-nginx/ingress-nginx
+```
+
+---
+layout: two-cols
+transition: fade
+hideInToc: true
+---
+
+# [Ingresses](https://kubernetes.io/docs/concepts/services-networking/ingress/)
+
+Ingress can be now provisioned by the nginx controller
+
+<v-clicks>
+
+When the controller receives an HTTP request matching the `Host` header and the path prefix, it will be redirected to the backend service
+
+</v-clicks>
+
+::right::
+
+````md magic-move[ingress-echo-server.yaml]{lines:true}
+<<<@/snippets/manifests/ingresses/ingress-echo-server.yaml yaml
+````
+
+<!--
+```shell
+kubectl apply -f ./snippets/manifests/ingresses/ingress-echo-server.yaml
+curl -H "Host: echo.example.org" http://{node_ip}:30080
+```
+-->
+
+---
+layout: two-cols
+transition: fade
+hideInToc: true
+---
+
+# [IngressClasses](https://kubernetes.io/docs/concepts/services-networking/ingress/#ingress-class)
+
+They allow specifying which controller should provision an `Ingress`
+
+<<< @/snippets/manifests/ingresses/ingress-nginx-class.yaml yaml{hide|all}{lines:true}
+
+::right::
+
+````md magic-move[ingress-echo-server.yaml]{lines:true}
+<<< @/snippets/manifests/ingresses/ingress-echo-server.yaml yaml{all}
+
+<<< @/snippets/manifests/ingresses/ingress-echo-server-class.yaml yaml{6}
+````

slides.md

@@ -64,6 +64,10 @@ src: ./pages/14-namespaces.md
 src: ./pages/20-helm.md
 ---
 
+---
+src: ./pages/21-ingresses.md
+---
+
 ---
 hideInToc: true
 ---