added documentation

kubernetes.md

@@ -0,0 +1,143 @@
+# Kubernetes Support
+
+## Requirements
+
+* Kubernetes 1.19+
+* Metrics service
+* An Ingress controller
+
+## Deployment
+
+Use the unofficial helm chart: https://github.com/jameswynn/helm-charts/tree/main/charts/homepage
+
+```sh
+helm repo add jameswynn https://jameswynn.github.io/helm-charts
+helm install my-release jameswynn/homepage
+```
+
+### Configuration
+
+Set the `mode` in the `kubernetes.yaml` to `cluster`.
+
+```yaml
+mode: default
+```
+
+## Widgets
+
+The Kubernetes widget can show a high-level overview of the cluster,
+individual nodes, or both.
+
+```yaml
+- kubernetes:
+    cluster:
+      # Shows the cluster node
+      show: true
+      # Shows the aggregate CPU stats
+      cpu: true
+      # Shows the aggregate memory stats
+      memory: true
+      # Shows a custom label
+      showLabel: true
+      label: "cluster"
+    nodes:
+      # Shows the clusters
+      show: true
+      # Shows the CPU for each node
+      cpu: true
+      # Shows the memory for each node
+      memory: true
+      # Shows the label, which is always the node name
+      showLabel: true
+```
+
+## Service Discovery
+
+Sample yaml:
+
+```yaml
+apiVersion: networking.k8s.io/v1
+kind: Ingress
+metadata:
+  name: homepage
+  annotations:
+    gethomepage.dev/enabled: "true"
+    gethomepage.dev/description: Dynamically Detected Homepage
+    gethomepage.dev/group: Operations
+    gethomepage.dev/icon: homepage.png
+    gethomepage.dev/name: Homepage
+spec:
+  rules:
+    - host: homepage.example.com
+      http:
+        paths:
+          - backend:
+              service:
+                name: homepage
+                port:
+                  number: 3000
+            path: /
+            pathType: Prefix
+```
+
+## Service Widgets
+
+To manually configure a Service Widget the `namespace` and `app` fields must
+be configured on the service entry.
+
+```yaml
+- Home Automation
+    - Home-Assistant:
+        icon: home-assistant.png
+        href: https://home.example.com
+        description: Home Automation
+        app: home-assistant
+        namespace: home
+```
+
+This works by creating a label selector `app.kubernetes.io/name=home-assistant`,
+which typically will be the same both for the ingress and the deployment. However,
+some deployments can be complex and will not conform to this rule. In such
+cases the `podSelector` variable can bridge the gap. Any field selector can
+be used in it which allows for some powerful selection capabilities.
+
+For instance, it can be utilized to roll multiple underlying deployments under
+one application to see a high-level aggregate:
+
+```yaml
+- Comms
+    - Element Chat:
+        icon: matrix-light.png
+        href: https://chat.example.com
+        description: Matrix Synapse Powered Chat
+        app: matrix-element
+        namespace: comms
+        podSelector: >-
+            app.kubernetes.io/instance in (
+                matrix-element,
+                matrix-media-repo,
+                matrix-media-repo-postgresql,
+                matrix-synapse
+            )
+```
+
+## Longhorn Widget
+
+There is a widget for showing storage stats from [Longhorn](https://longhorn.io).
+Configure it from the `widgets.yaml`.
+
+```yaml
+- longhorn:
+    # Show the expanded
+    expanded: true
+    # Shows a node representing the aggregate values
+    total: true
+    # Shows the node names as labels
+    labels: true
+    # Show the nodes
+    nodes: true
+    # An explicit list of nodes to show. All are shown by default if "nodes" is true
+    include:
+      - node1
+      - node2
+```