Adjustments to interface with gcp and external-cloud-provider (#15)

* Prepare for clouds which don't yet support external-cloud-provider

* Remove warning aboug GCP cloud-provider, added unit tests

* formatting

charms/kubernetes_snaps.py

@@ -81,9 +81,9 @@ def configure_apiserver(
     api_opts["service-account-issuer"] = "https://kubernetes.default.svc"
     api_opts["service-account-signing-key-file"] = str(service_account_key_path)
     api_opts["service-account-key-file"] = str(service_account_key_path)
-    api_opts[
-        "kubelet-preferred-address-types"
-    ] = "InternalIP,Hostname,InternalDNS,ExternalDNS,ExternalIP"
+    api_opts["kubelet-preferred-address-types"] = (
+        "InternalIP,Hostname,InternalDNS,ExternalDNS,ExternalIP"
+    )
     # TODO: encryption at rest
     # api_opts["encryption-provider-config"] = str(encryption_config_path())
 
@@ -159,16 +159,10 @@ def configure_apiserver(
     api_opts["client-ca-file"] = "/root/cdk/ca.crt"
 
     if external_cloud_provider.has_xcp:
+        log.info("KubeApi: Uses an External Cloud Provider")
         api_opts["cloud-provider"] = "external"
-
-    if external_cloud_provider.name == "gce":
-        # TODO: We need a charm for external-cloud-provider for GCP
-        # based on https://github.com/kubernetes/cloud-provider-gcp/
-        log.warning(
-            "GCP cloud-provider is currently available in-tree "
-            "but can be avoided configuring here if we use the "
-            "external tree provider"
-        )
+    else:
+        log.info("KubeApi: No Cloud Features")
 
     api_opts["feature-gates"] = ",".join(feature_gates)
 
@@ -229,16 +223,10 @@ def configure_controller_manager(
     feature_gates = ["RotateKubeletServerCertificate=true"]
 
     if external_cloud_provider.has_xcp:
+        log.info("KubeController: Uses an External Cloud Provider")
         controller_opts["cloud-provider"] = "external"
-
-    if external_cloud_provider.name == "gce":
-        # TODO: We need a charm for external-cloud-provider for GCP
-        # based on https://github.com/kubernetes/cloud-provider-gcp/
-        log.warning(
-            "GCP cloud-provider is currently available in-tree "
-            "but can be avoided configuring here if we use the "
-            "external tree provider"
-        )
+    else:
+        log.info("KubeController: No Cloud Features")
 
     controller_opts["feature-gates"] = ",".join(feature_gates)
 
@@ -371,23 +359,18 @@ def configure_kubelet(
     kubelet_opts["hostname-override"] = get_node_name(fqdn)
     kubelet_opts["config"] = "/root/cdk/kubelet/config.yaml"
     if external_cloud_provider.has_xcp:
+        log.info("Kubelet: Uses an External Cloud Provider")
         kubelet_opts["cloud-provider"] = "external"
-
-    if external_cloud_provider.name == "gce":
-        # TODO: We need a charm for external-cloud-provider for GCP
-        # based on https://github.com/kubernetes/cloud-provider-gcp/
-        log.warning(
-            "GCP cloud-provider is currently available in-tree "
-            "but can be avoided configuring here if we use the "
-            "external tree provider"
-        )
+    else:
+        log.info("Kubelet: No Cloud Features")
 
     # Add kubelet-extra-config. This needs to happen last so that it
     # overrides any config provided by the charm.
     merge_extra_config(kubelet_config, extra_config)
 
-    os.makedirs("/root/cdk/kubelet", exist_ok=True)
-    with open("/root/cdk/kubelet/config.yaml", "w") as f:
+    p = Path("/root/cdk/kubelet/config.yaml")
+    p.parent.mkdir(parents=True, exist_ok=True)
+    with p.open("w") as f:
         f.write("# Generated by charm, do not edit\n")
         yaml.dump(kubelet_config, f)
 

tests/unit/test_kubernetes_snaps.py

@@ -61,3 +61,48 @@ def test_is_channel_swap(subprocess_call, subprocess_check_output):
     assert kubernetes_snaps.is_channel_swap("my-snap", "1.28/stable")
     assert not kubernetes_snaps.is_channel_swap("my-snap", "1.29/stable")
     assert kubernetes_snaps.is_channel_swap("my-snap", "1.30/stable")
+
+
+@pytest.fixture(params=[None, "external"])
+def external_cloud(request):
+    cloud = mock.MagicMock()
+    cloud.has_xcp = request.param == "external"
+    cloud.in_tree.return_value = {}
+    yield cloud
+
+
+@mock.patch("charms.kubernetes_snaps.configure_kubernetes_service")
+@mock.patch("charms.kubernetes_snaps.Path")
+def test_configure_kubelet(
+    mock_path,
+    configure_kubernetes_service,
+    external_cloud,
+):
+    kubernetes_snaps.configure_kubelet(
+        "container_runtime_endpoint",
+        "dns_domain",
+        "dns_ip",
+        {},
+        {},
+        external_cloud,
+        "kubeconfig",
+        "node_ip",
+        "registry.io",
+        ["taint:NoExecute"],
+    )
+    configure_kubernetes_service.assert_called_once()
+    service, args, extra = configure_kubernetes_service.call_args[0]
+    assert service == "kubelet"
+    assert extra == {}
+    expected_args = {
+        "kubeconfig": "kubeconfig",
+        "v": "0",
+        "node-ip": "node_ip",
+        "container-runtime-endpoint": "container_runtime_endpoint",
+        "hostname-override": kubernetes_snaps.get_node_name(),
+        "config": "/root/cdk/kubelet/config.yaml",
+        **external_cloud.in_tree.return_value,
+    }
+    if external_cloud.has_xcp:
+        expected_args["cloud-provider"] = "external"
+    assert expected_args == args