| // Copyright Istio 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 merge |
| |
| /* |
| CODE Copied and modified from https://github.com/kumahq/kuma/blob/master/pkg/util/proto/google_proto.go |
| because of: https://github.com/golang/protobuf/issues/1359 |
| |
| Copyright 2019 The Go Authors. All rights reserved. |
| Use of this source code is governed by a BSD-style |
| license that can be found in the LICENSE file. |
| */ |
| |
| import ( |
| "fmt" |
| ) |
| |
| import ( |
| "google.golang.org/protobuf/proto" |
| "google.golang.org/protobuf/reflect/protoreflect" |
| "google.golang.org/protobuf/types/known/durationpb" |
| ) |
| |
| type ( |
| MergeFunction func(dst, src protoreflect.Message) |
| mergeOptions struct { |
| customMergeFn map[protoreflect.FullName]MergeFunction |
| } |
| ) |
| type OptionFn func(options mergeOptions) mergeOptions |
| |
| func MergeFunctionOptionFn(name protoreflect.FullName, function MergeFunction) OptionFn { |
| return func(options mergeOptions) mergeOptions { |
| options.customMergeFn[name] = function |
| return options |
| } |
| } |
| |
| // ReplaceMergeFn instead of merging all subfields one by one, takes src and set it to dest |
| var ReplaceMergeFn MergeFunction = func(dst, src protoreflect.Message) { |
| dst.Range(func(fd protoreflect.FieldDescriptor, v protoreflect.Value) bool { |
| dst.Clear(fd) |
| return true |
| }) |
| src.Range(func(fd protoreflect.FieldDescriptor, v protoreflect.Value) bool { |
| dst.Set(fd, v) |
| return true |
| }) |
| } |
| |
| var options = []OptionFn{ |
| // Workaround https://github.com/golang/protobuf/issues/1359, merge duration properly |
| MergeFunctionOptionFn((&durationpb.Duration{}).ProtoReflect().Descriptor().FullName(), ReplaceMergeFn), |
| } |
| |
| func Merge(dst, src proto.Message) { |
| merge(dst, src, options...) |
| } |
| |
| // Merge Code of proto.Merge with modifications to support custom types |
| func merge(dst, src proto.Message, opts ...OptionFn) { |
| mo := mergeOptions{customMergeFn: map[protoreflect.FullName]MergeFunction{}} |
| for _, opt := range opts { |
| mo = opt(mo) |
| } |
| dstMsg, srcMsg := dst.ProtoReflect(), src.ProtoReflect() |
| if dstMsg.Descriptor() != srcMsg.Descriptor() { |
| if got, want := dstMsg.Descriptor().FullName(), srcMsg.Descriptor().FullName(); got != want { |
| panic(fmt.Sprintf("descriptor mismatch: %v != %v", got, want)) |
| } |
| panic("descriptor mismatch") |
| } |
| mo.mergeMessage(dstMsg, srcMsg) |
| } |
| |
| func (o mergeOptions) mergeMessage(dst, src protoreflect.Message) { |
| // The regular proto.mergeMessage would have a fast path method option here. |
| // As we want to have exceptions we always use the slow path. |
| if !dst.IsValid() { |
| panic(fmt.Sprintf("cannot merge into invalid %v message", dst.Descriptor().FullName())) |
| } |
| |
| src.Range(func(fd protoreflect.FieldDescriptor, v protoreflect.Value) bool { |
| switch { |
| case fd.IsList(): |
| o.mergeList(dst.Mutable(fd).List(), v.List(), fd) |
| case fd.IsMap(): |
| o.mergeMap(dst.Mutable(fd).Map(), v.Map(), fd.MapValue()) |
| case fd.Message() != nil: |
| mergeFn, exists := o.customMergeFn[fd.Message().FullName()] |
| if exists { |
| mergeFn(dst.Mutable(fd).Message(), v.Message()) |
| } else { |
| o.mergeMessage(dst.Mutable(fd).Message(), v.Message()) |
| } |
| case fd.Kind() == protoreflect.BytesKind: |
| dst.Set(fd, o.cloneBytes(v)) |
| default: |
| dst.Set(fd, v) |
| } |
| return true |
| }) |
| |
| if len(src.GetUnknown()) > 0 { |
| dst.SetUnknown(append(dst.GetUnknown(), src.GetUnknown()...)) |
| } |
| } |
| |
| func (o mergeOptions) mergeList(dst, src protoreflect.List, fd protoreflect.FieldDescriptor) { |
| // Merge semantics appends to the end of the existing list. |
| for i, n := 0, src.Len(); i < n; i++ { |
| switch v := src.Get(i); { |
| case fd.Message() != nil: |
| dstv := dst.NewElement() |
| o.mergeMessage(dstv.Message(), v.Message()) |
| dst.Append(dstv) |
| case fd.Kind() == protoreflect.BytesKind: |
| dst.Append(o.cloneBytes(v)) |
| default: |
| dst.Append(v) |
| } |
| } |
| } |
| |
| func (o mergeOptions) mergeMap(dst, src protoreflect.Map, fd protoreflect.FieldDescriptor) { |
| // Merge semantics replaces, rather than merges into existing entries. |
| src.Range(func(k protoreflect.MapKey, v protoreflect.Value) bool { |
| switch { |
| case fd.Message() != nil: |
| dstv := dst.NewValue() |
| o.mergeMessage(dstv.Message(), v.Message()) |
| dst.Set(k, dstv) |
| case fd.Kind() == protoreflect.BytesKind: |
| dst.Set(k, o.cloneBytes(v)) |
| default: |
| dst.Set(k, v) |
| } |
| return true |
| }) |
| } |
| |
| func (o mergeOptions) cloneBytes(v protoreflect.Value) protoreflect.Value { |
| return protoreflect.ValueOfBytes(append([]byte{}, v.Bytes()...)) |
| } |