feat: add coredns (#6)

We had some inconsistencies with node configuration and dns hickups.
This feature moves the coredns config into our software versioning system.

Reviewed-on: #6
Co-authored-by: Timo Behrendt <t.behrendt@t00n.de>
Co-committed-by: Timo Behrendt <t.behrendt@t00n.de>

.gitea/workflows/deploy.yaml

@@ -10,6 +10,7 @@ jobs:
     runs-on: ubuntu-latest
     outputs:
       node-labels: ${{ steps.filter.outputs.node-labels }}
+      coredns: ${{ steps.filter.outputs.coredns }}
     steps:
       - uses: actions/checkout@v5
         with:
@@ -20,6 +21,8 @@ jobs:
           filters: |
             k8s:
               - 'node-labels/**'
+            coredns:
+              - 'coredns/**'
 
   deploy-node-labels:
     runs-on: ubuntu-latest
@@ -35,3 +38,18 @@ jobs:
       - name: Deploy
         run: |
           kubectl apply --server-side --field-manager=t000-n -f node-labels
+
+  deploy-coredns:
+    runs-on: ubuntu-latest
+    needs: check-changes
+    if: ${{ needs.check-changes.outputs.coredns == 'true' }}
+    steps:
+      - uses: actions/checkout@v5
+      - uses: azure/setup-kubectl@v4
+      - uses: azure/k8s-set-context@v4
+        with:
+          method: kubeconfig
+          kubeconfig: ${{ secrets.KUBECONFIG }}
+      - name: Deploy
+        run: |
+          kubectl apply -n kube-system -f coredns

.gitea/workflows/validate.yaml

@@ -18,3 +18,16 @@ jobs:
       - name: Validate
         run: |
           kubectl apply --server-side --field-manager=t000-n --dry-run=server -f node-labels
+
+  validate-coredns:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v5
+      - uses: azure/setup-kubectl@v4
+      - uses: azure/k8s-set-context@v4
+        with:
+          method: kubeconfig
+          kubeconfig: ${{ secrets.KUBECONFIG }}
+      - name: Validate
+        run: |
+          kubectl apply -n kube-system -f coredns