feat(metallb): generate address pool automatically

metal/cluster.yml

@@ -2,3 +2,10 @@
   hosts: metal
   roles:
     - k3s
+
+- name: Create some basic config
+  hosts: localhost
+  environment:
+    KUBECONFIG: ./kubeconfig.yaml
+  roles:
+    - metallb_config

metal/roles/metallb_config/defaults/main.yml

@@ -0,0 +1,9 @@
+metallb_namespace: metallb-system
+metallb_subnet_cidr_prefix: 27  # /27
+metallb_subnet_index: -1  # last subnet
+metallb_addresses: |  # Use the last subnet with the specified size from the network
+  {{
+    (ansible_default_ipv4.network + '/' + ansible_default_ipv4.netmask)
+      | ansible.netcommon.ipaddr('net')
+      | ansible.netcommon.ipsubnet(metallb_subnet_cidr_prefix, metallb_subnet_index)
+  }}

metal/roles/metallb_config/tasks/main.yml

@@ -0,0 +1,10 @@
+- name: Ensure MetalLB namespace exist
+  kubernetes.core.k8s:
+    api_version: v1
+    kind: Namespace
+    name: "{{ metallb_namespace }}"
+    state: present
+
+- name: Create MetalLB config base on network info
+  kubernetes.core.k8s:
+    definition: "{{ lookup('template', 'configmap.yaml.j2') | from_yaml }}"

metal/roles/metallb_config/templates/configmap.yaml.j2

@@ -0,0 +1,12 @@
+apiVersion: v1
+kind: ConfigMap
+metadata:
+  name: metallb-config
+  namespace: {{ metallb_namespace }}
+data:
+  config: |
+    address-pools:
+      - name: default
+        protocol: layer2
+        addresses:
+          - {{ metallb_addresses }}

system/metallb-system/values.yaml

@@ -1,8 +1,2 @@
 metallb:
-  configInline:
-    address-pools:
-      - name: default
-        protocol: layer2
-        addresses:
-          # TODO (optimize) Use metal values for MetalLB values
-          - 192.168.1.150-192.168.1.180
+  existingConfigMap: metallb-config