feature: add methods to get annotations

pkg/utils/kube/kube.go

@@ -129,10 +129,21 @@ func MustToUnstructured(obj interface{}) *unstructured.Unstructured {
 
 // GetAppInstanceLabel returns the application instance name from labels
 func GetAppInstanceLabel(un *unstructured.Unstructured, key string) string {
-	if labels := un.GetLabels(); labels != nil {
-		return labels[key]
+	return un.GetLabels()[key]
+}
+
+// GetAppInstanceAnnotation returns the application instance name from annotations
+func GetAppInstanceAnnotation(un *unstructured.Unstructured, key string) string {
+	return un.GetAnnotations()[key]
+}
+
+// GetAppInstanceIdentifier returns the application instance name from annotations else labels
+func GetAppInstanceIdentifier(un *unstructured.Unstructured, key string) string {
+	annotation := GetAppInstanceAnnotation(un, key)
+	if annotation != "" {
+		return annotation
 	}
-	return ""
+	return GetAppInstanceLabel(un, key)
 }
 
 // UnsetLabel removes our app labels from an unstructured object

pkg/utils/kube/kube_test.go

@@ -20,6 +20,8 @@ metadata:
   name: nginx-deployment
   labels:
     foo: bar
+  annotations:
+    foo: bar-annotations
 spec:
   template:
     metadata:
@@ -155,3 +157,36 @@ func TestSplitYAML_TrailingNewLines(t *testing.T) {
 	require.NoError(t, err)
 	assert.Len(t, objs, 1)
 }
+
+func TestGetLabels(t *testing.T) {
+	for _, yamlStr := range [][]byte{[]byte(depWithLabel)} {
+		var obj unstructured.Unstructured
+		err := yaml.Unmarshal(yamlStr, &obj)
+		require.NoError(t, err)
+
+		value := GetAppInstanceLabel(&obj, "foo")
+		assert.Equal(t, "bar", value)
+	}
+}
+
+func TestGetAnnotations(t *testing.T) {
+	for _, yamlStr := range [][]byte{[]byte(depWithLabel)} {
+		var obj unstructured.Unstructured
+		err := yaml.Unmarshal(yamlStr, &obj)
+		require.NoError(t, err)
+
+		value := GetAppInstanceAnnotation(&obj, "foo")
+		assert.Equal(t, "bar-annotations", value)
+	}
+}
+
+func TestGetIdentifier(t *testing.T) {
+	for _, yamlStr := range [][]byte{[]byte(depWithLabel)} {
+		var obj unstructured.Unstructured
+		err := yaml.Unmarshal(yamlStr, &obj)
+		require.NoError(t, err)
+
+		value := GetAppInstanceIdentifier(&obj, "foo")
+		assert.Equal(t, "bar-annotations", value)
+	}
+}