Add a way to modify the component objects

Author: asalkeld

cmd/clusterctl/client/repository/components.go

@@ -144,6 +144,25 @@ func (c *components) Yaml() ([]byte, error) {
 	return utilyaml.FromUnstructured(c.objs)
 }
 
+// ComponentsAlterFn defines the function that is used to alter the components.Objs().
+type ComponentsAlterFn func(objs []unstructured.Unstructured) ([]unstructured.Unstructured, error)
+
+// AlterComponents provides a mechanism to alter the component.Objs from outside
+// the repository module.
+func AlterComponents(comps Components, alterFn ComponentsAlterFn) error {
+	c, ok := comps.(*components)
+	if !ok {
+		return errors.New("could not alter components as Components is not of the correct type")
+	}
+
+	alteredObjs, err := alterFn(c.Objs())
+	if err != nil {
+		return err
+	}
+	c.objs = alteredObjs
+	return nil
+}
+
 // ComponentsOptions represents specific inputs that are passed in to
 // clusterctl library. These are user specified inputs.
 type ComponentsOptions struct {

cmd/clusterctl/client/repository/components_test.go

@@ -948,3 +948,40 @@ func Test_addCommonLabels(t *testing.T) {
 		})
 	}
 }
+
+func TestAlterComponents(t *testing.T) {
+	c := &components{
+		targetNamespace: "test-ns",
+		objs: []unstructured.Unstructured{
+			{
+				Object: map[string]interface{}{
+					"kind": "ClusterRole",
+				},
+			},
+		},
+	}
+	want := []unstructured.Unstructured{
+		{
+			Object: map[string]interface{}{
+				"kind": "ClusterRole",
+				"metadata": map[string]interface{}{
+					"labels": map[string]interface{}{
+						clusterctlv1.ClusterctlLabelName: "",
+						clusterv1.ProviderLabelName:      "infrastructure-provider",
+					},
+				},
+			},
+		},
+	}
+
+	alterFn := func(objs []unstructured.Unstructured) ([]unstructured.Unstructured, error) {
+		// reusing addCommonLabels to do an example modification.
+		return addCommonLabels(objs, config.NewProvider("provider", "", clusterctlv1.InfrastructureProviderType)), nil
+	}
+
+	g := NewWithT(t)
+	if err := AlterComponents(c, alterFn); err != nil {
+		t.Errorf("AlterComponents() error = %v", err)
+	}
+	g.Expect(c.objs).To(Equal(want))
+}