feat: add k3s deployment and service configurations for ok-server

README.md

@@ -96,6 +96,50 @@ container run --rm -d --name ok-server -c 1 -m 256m -p 8080:8080 ok-server
 
 This will start the server and expose it on port 8080. The container will run until stopped, and will be removed when stopped. You can stop it with `container stop ok-server`.
 
+### nerdctl with BuildKit on a k3s server
+
+Build the image directly into the containerd instance used by k3s:
+
+```bash
+sudo nerdctl build -t ok-server .
+sudo nerdctl images
+```
+
+On a single-node k3s cluster the image is now available to the kubelet without a
+registry. The [k3s/deployment.yaml](k3s/deployment.yaml) Deployment references
+it with `imagePullPolicy: Never`:
+
+```bash
+kubectl apply -f k3s/deployment.yaml
+```
+
+Expose the app with one of the two options below.
+
+#### Option 1: Traefik Ingress
+
+k3s includes the Traefik ingress controller. The ClusterIP Service and Ingress
+in [k3s/expose-ingress.yaml](k3s/expose-ingress.yaml) expose the app on port 80
+of the node's IP address:
+
+```bash
+kubectl apply -f k3s/expose-ingress.yaml
+curl -si "http://<node-ip>/"
+```
+
+#### Option 2: ServiceLB
+
+k3s also includes the ServiceLB load balancer. The single `LoadBalancer`
+Service in [k3s/expose-servicelb.yaml](k3s/expose-servicelb.yaml) exposes the
+app on port 8080 of the node's IP address, without an Ingress:
+
+```bash
+kubectl apply -f k3s/expose-servicelb.yaml
+curl -si "http://<node-ip>:8080"
+```
+
+On a multi-node cluster, push the image to a registry instead, so every node can
+pull it.
+
 ## License
 
 This project is licensed under the MIT License. See the [LICENSE](LICENSE) file for details.

k3s/deployment.yaml

@@ -0,0 +1,20 @@
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: ok-server
+spec:
+  replicas: 1
+  selector:
+    matchLabels:
+      app: ok-server
+  template:
+    metadata:
+      labels:
+        app: ok-server
+    spec:
+      containers:
+        - name: ok-server
+          image: ok-server
+          imagePullPolicy: Never
+          ports:
+            - containerPort: 8080

k3s/expose-ingress.yaml

@@ -0,0 +1,26 @@
+apiVersion: v1
+kind: Service
+metadata:
+  name: ok-server
+spec:
+  selector:
+    app: ok-server
+  ports:
+    - port: 8080
+      targetPort: 8080
+---
+apiVersion: networking.k8s.io/v1
+kind: Ingress
+metadata:
+  name: ok-server
+spec:
+  rules:
+    - http:
+        paths:
+          - path: /
+            pathType: Prefix
+            backend:
+              service:
+                name: ok-server
+                port:
+                  number: 8080

k3s/expose-servicelb.yaml

@@ -0,0 +1,11 @@
+apiVersion: v1
+kind: Service
+metadata:
+  name: ok-server
+spec:
+  type: LoadBalancer
+  selector:
+    app: ok-server
+  ports:
+    - port: 8080
+      targetPort: 8080