fix: patch with delete for LinkConfigs

smira · smira · commit db9ff23ae37d · 2026-03-06T19:17:39.000+04:00
There were two issues which prevented this patch from working: * `CommonLinkConfig` is an embedded struct, so we need to make selector descend into embedded structs properly * The previous `reflect.Value.String()` doesn't handle correctly complex values (like `netip.Prefix`) which have a custom `fmt.Stringer` See #12848 (reply in thread) Signed-off-by: Andrey Smirnov <andrey.smirnov@siderolabs.com> (cherry picked from commit c1d0a33)
diff --git a/pkg/machinery/config/configloader/internal/decoder/selector.go b/pkg/machinery/config/configloader/internal/decoder/selector.go
@@ -134,7 +134,7 @@ var searchForType = reflect.TypeFor[string]()
 // ErrLookupFailed is returned when the lookup failed.
 var ErrLookupFailed = errors.New("lookup failed")
 
-//nolint:gocyclo
+//nolint:gocyclo,cyclop
 func deleteForPath(val reflect.Value, path []string, key, value string) error {
 	if len(path) == 0 {
 		return errors.New("path is empty")
@@ -173,6 +173,20 @@ func deleteForPath(val reflect.Value, path []string, key, value string) error {
 
 				return deleteForPath(val.Field(i), path, key, value)
 			}
+
+			// if there is an embedded struct, descend into it
+			if len(yamlTags) > 1 && yamlTags[0] == "" && yamlTags[1] == "inline" {
+				err := deleteForPath(val.Field(i), append([]string{searchFor}, path...), key, value)
+				if err == nil {
+					// value found & deleted
+					return nil
+				}
+
+				// ignore lookup failed errors, we can continue with other fields
+				if !errors.Is(err, ErrLookupFailed) {
+					return err
+				}
+			}
 		}
 	case reflect.Map:
 		if val.IsNil() {
@@ -246,7 +260,17 @@ func deleteStructFrom(searchIn reflect.Value, searchFor string, path []string, k
 					continue
 				}
 
-				if elem.Field(j).String() != value {
+				fieldVal := elem.Field(j)
+				fieldStr := fieldVal.String()
+
+				// if the field value implements Stringer, use it for comparison instead of the default string conversion
+				if fieldVal.CanInterface() {
+					if stringer, ok := fieldVal.Interface().(fmt.Stringer); ok {
+						fieldStr = stringer.String()
+					}
+				}
+
+				if fieldStr != value {
 					continue
 				}
 
diff --git a/pkg/machinery/config/configpatcher/apply_test.go b/pkg/machinery/config/configpatcher/apply_test.go
@@ -2,6 +2,7 @@
 // License, v. 2.0. If a copy of the MPL was not distributed with this
 // file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
+//nolint:dupl
 package configpatcher_test
 
 import (
@@ -325,3 +326,43 @@ func TestPatchDeleteMissing(t *testing.T) {
 		})
 	}
 }
+
+//go:embed testdata/patchlink/base.yaml
+var configPatchBase []byte
+
+//go:embed testdata/patchlink/expected.yaml
+var configPatchExpected string
+
+func TestPatchLink(t *testing.T) {
+	patches, err := configpatcher.LoadPatches([]string{
+		"@testdata/patchlink/patch.yaml",
+	})
+	require.NoError(t, err)
+
+	cfg, err := configloader.NewFromBytes(configPatchBase)
+	require.NoError(t, err)
+
+	for _, tt := range []struct {
+		name  string
+		input configpatcher.Input
+	}{
+		{
+			name:  "WithConfig",
+			input: configpatcher.WithConfig(cfg),
+		},
+		{
+			name:  "WithBytes",
+			input: configpatcher.WithBytes(configPatchBase),
+		},
+	} {
+		t.Run(tt.name, func(t *testing.T) {
+			out, err := configpatcher.Apply(tt.input, patches)
+			require.NoError(t, err)
+
+			bytes, err := out.Bytes()
+			require.NoError(t, err)
+
+			assert.Equal(t, configPatchExpected, string(bytes))
+		})
+	}
+}
diff --git a/pkg/machinery/config/configpatcher/testdata/patchlink/base.yaml b/pkg/machinery/config/configpatcher/testdata/patchlink/base.yaml
@@ -0,0 +1,7 @@
+apiVersion: v1alpha1
+kind: LinkConfig
+name: eth0
+addresses:
+  - address: 10.0.42.136/24
+routes:
+  - gateway: 10.0.42.1
diff --git a/pkg/machinery/config/configpatcher/testdata/patchlink/expected.yaml b/pkg/machinery/config/configpatcher/testdata/patchlink/expected.yaml
@@ -0,0 +1,7 @@
+apiVersion: v1alpha1
+kind: LinkConfig
+name: eth0
+addresses:
+    - address: 10.0.42.137/24
+routes:
+    - gateway: 10.0.42.1
diff --git a/pkg/machinery/config/configpatcher/testdata/patchlink/patch.yaml b/pkg/machinery/config/configpatcher/testdata/patchlink/patch.yaml
@@ -0,0 +1,7 @@
+apiVersion: v1alpha1
+kind: LinkConfig
+name: eth0
+addresses:
+  - address: 10.0.42.136/24
+    $patch: delete
+  - address: 10.0.42.137/24
