tidy and improve cos integration workflow

also fix the juju-channel in k8s controller

.github/workflows/cos_integration.yaml

@@ -1,4 +1,4 @@
-name: Integration tests with COS
+name: COS Integration tests
 
 on:
   workflow_call:
@@ -11,48 +11,62 @@ on:
       - "**.rst"
 
 jobs:
-  integration-tests-with-cos:
-    runs-on: ubuntu-latest
+  integration:
+    runs-on: ubuntu-22.04
     timeout-minutes: 120
     steps:
       - name: Checkout
         uses: actions/checkout@v3
+
       - name: Get IP address of the host
         run: |
           # Finding preferred source ip address by trying to reach destination 2.2.2.2
           # This ip address will be used while enabling metallb
           echo "IPADDR=$(ip -4 -j route get 2.2.2.2 | jq -r '.[] | .prefsrc')" >> $GITHUB_ENV
+
       - name: Setup lxd controller
         uses: charmed-kubernetes/actions-operator@main
         with:
           # The juju version can be any stable version, as long as it is the same as libjuju version used.
-          # If you updated it here, update it also in tests/integration/requirements.txt
+          # If you update it here, update it also in tests/integration/requirements.txt and 'Setup k8s controller' step below
           juju-channel: 3.5/stable
           provider: lxd
+
       - name: Save lxd controller name
         id: lxd-controller
         # The `CONTROLLER_NAME` envvar is set by the actions-operator action
         run: echo "name=$CONTROLLER_NAME" >> $GITHUB_OUTPUT
+
       - name: Setup k8s controller
         uses: charmed-kubernetes/actions-operator@main
         with:
-          juju-channel: 3.1/stable
+          # The juju version can be any stable version, as long as it is the same as libjuju version used.
+          # If you update it here, update it also in tests/integration/requirements.txt and 'Setup lxd controller' step above
+          juju-channel: 3.5/stable
           provider: microk8s
           channel: 1.28-strict/stable
           microk8s-addons: "hostpath-storage dns metallb:${{ env.IPADDR }}-${{ env.IPADDR }}"
+
       - name: Save k8s controller name
         id: k8s-controller
         # The `CONTROLLER_NAME` envvar is set by the actions-operator action
         run: echo "name=$CONTROLLER_NAME" >> $GITHUB_OUTPUT
+
       - name: Fix microk8s permissions
-        run: |
-          chmod -R ugo+rwX ~/.kube
+        run: chmod -R ugo+rwX ~/.kube
+
       - name: Run integration tests
         run: tox -e integration
         env:
           K8S_CONTROLLER: ${{ steps.k8s-controller.outputs.name }}
           LXD_CONTROLLER: ${{ steps.lxd-controller.outputs.name }}
+
       - name: Dump debug log
         if: failure()
-        run: for ctl in $(juju controllers --format json | jq -r '.controllers | keys[]'); do for mdl in $(juju models --format json | jq -r '.models[].name' | grep -v "admin/controller"); do juju debug-log -m $ctl:$mdl --replay --ms --no-tail; done; done || true
+        run: |
+          for ctl in $(juju controllers --format json | jq -r '.controllers | keys[]'); do
+            for mdl in $(juju models --format json | jq -r '.models[].name' | grep -v "admin/controller"); do
+              juju debug-log -m $ctl:$mdl --replay --ms --no-tail
+            done
+          done || true
         shell: bash