Add merge support for serviceaccounts

All properties from a backup will be merged into the ServiceAccount
except for the default token secret.

Signed-off-by: Nolan Brubaker <nolan@heptio.com>

pkg/util/collections/map_utils.go

@@ -122,3 +122,14 @@ func Exists(root map[string]interface{}, path string) bool {
 	_, err := GetValue(root, path)
 	return err == nil
 }
+
+// MergeMaps takes two map[string]string and merges missing keys from the second into the first.
+// If a key already exists, its value is not overwritten.
+func MergeMaps(first, second map[string]string) {
+	for k, v := range second {
+		_, ok := first[k]
+		if !ok {
+			first[k] = v
+		}
+	}
+}

pkg/util/collections/map_utils_test.go

@@ -16,7 +16,9 @@ limitations under the License.
 
 package collections
 
-import "testing"
+import (
+	"testing"
+)
 
 func TestGetString(t *testing.T) {
 	var testCases = []struct {

pkg/util/test/fake_dynamic.go

@@ -64,3 +64,8 @@ func (c *FakeDynamicClient) Get(name string, opts metav1.GetOptions) (*unstructu
 	args := c.Called(name, opts)
 	return args.Get(0).(*unstructured.Unstructured), args.Error(1)
 }
+
+func (c *FakeDynamicClient) Patch(name string, data []byte) (*unstructured.Unstructured, error) {
+	args := c.Called(name, data)
+	return args.Get(0).(*unstructured.Unstructured), args.Error(1)
+}