build source

vendor/k8s.io/apimachinery/pkg/api/validate/item.go

@@ -0,0 +1,77 @@
+/*
+Copyright 2024 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package validate
+
+import (
+	"context"
+
+	"k8s.io/apimachinery/pkg/api/operation"
+	"k8s.io/apimachinery/pkg/util/validation/field"
+)
+
+// MatchItemFn takes a pointer to an item and returns true if it matches the criteria.
+type MatchItemFn[T any] func(*T) bool
+
+// SliceItem finds the first item in newList that satisfies the match function,
+// and if found, also looks for a matching item in oldList. If the value of the
+// item is the same as the previous value, as per the equiv function, then no
+// validation is performed. Otherwise, it invokes 'itemValidator' on these items.
+//
+// This function processes only the *first* matching item found in newList. It
+// assumes that the match functions targets a unique identifier (primary key)
+// and will match at most one element per list. If this assumption is violated,
+// changes in list order can lead this function to have inconsistent behavior.
+//
+// The fldPath passed to itemValidator is indexed to the matched item's
+// position in newList.
+//
+// This function does not validate items that were removed (present in oldList
+// but not in newList).
+func SliceItem[TList ~[]TItem, TItem any](
+	ctx context.Context, op operation.Operation, fldPath *field.Path,
+	newList, oldList TList,
+	matches MatchItemFn[TItem],
+	equiv MatchFunc[TItem],
+	itemValidator func(ctx context.Context, op operation.Operation, fldPath *field.Path, newObj, oldObj *TItem) field.ErrorList,
+) field.ErrorList {
+	var matchedNew, matchedOld *TItem
+	var newIndex int
+
+	for i := range newList {
+		if matches(&newList[i]) {
+			matchedNew = &newList[i]
+			newIndex = i
+			break
+		}
+	}
+	if matchedNew == nil {
+		return nil
+	}
+
+	for i := range oldList {
+		if matches(&oldList[i]) {
+			matchedOld = &oldList[i]
+			break
+		}
+	}
+
+	if op.Type == operation.Update && matchedOld != nil && equiv(*matchedNew, *matchedOld) {
+		return nil
+	}
+
+	return itemValidator(ctx, op, fldPath.Index(newIndex), matchedNew, matchedOld)
+}