| // Copyright 2018 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. |
| |
| // This file contains functions for fetching the options for a protoreflect descriptor. |
| // |
| // TODO: Replace this with the appropriate protoreflect API, once it exists. |
| |
| package main |
| |
| import ( |
| "github.com/golang/protobuf/proto" |
| descpb "github.com/golang/protobuf/protoc-gen-go/descriptor" |
| "github.com/golang/protobuf/v2/protogen" |
| "github.com/golang/protobuf/v2/reflect/protoreflect" |
| ) |
| |
| // messageOptions returns the MessageOptions for a message. |
| func messageOptions(gen *protogen.Plugin, message *protogen.Message) *descpb.MessageOptions { |
| d := getDescriptorProto(gen, message.Desc, message.Path) |
| if d == nil { |
| return nil |
| } |
| return d.(*descpb.DescriptorProto).GetOptions() |
| } |
| |
| // fieldOptions returns the FieldOptions for a message. |
| func fieldOptions(gen *protogen.Plugin, field *protogen.Field) *descpb.FieldOptions { |
| d := getDescriptorProto(gen, field.Desc, field.Path) |
| if d == nil { |
| return nil |
| } |
| return d.(*descpb.FieldDescriptorProto).GetOptions() |
| } |
| |
| // enumOptions returns the EnumOptions for an enum |
| func enumOptions(gen *protogen.Plugin, enum *protogen.Enum) *descpb.EnumOptions { |
| d := getDescriptorProto(gen, enum.Desc, enum.Path) |
| if d == nil { |
| return nil |
| } |
| return d.(*descpb.EnumDescriptorProto).GetOptions() |
| } |
| |
| // enumValueOptions returns the EnumValueOptions for an enum value |
| func enumValueOptions(gen *protogen.Plugin, value *protogen.EnumValue) *descpb.EnumValueOptions { |
| d := getDescriptorProto(gen, value.Desc, value.Path) |
| if d == nil { |
| return nil |
| } |
| return d.(*descpb.EnumValueDescriptorProto).GetOptions() |
| } |
| |
| func getDescriptorProto(gen *protogen.Plugin, desc protoreflect.Descriptor, path []int32) proto.Message { |
| var p proto.Message |
| // Look up the FileDescriptorProto. |
| for { |
| if fdesc, ok := desc.(protoreflect.FileDescriptor); ok { |
| file, ok := gen.FileByName(fdesc.Path()) |
| if !ok { |
| return nil |
| } |
| p = file.Proto |
| break |
| } |
| var ok bool |
| desc, ok = desc.Parent() |
| if !ok { |
| return nil |
| } |
| } |
| const ( |
| // field numbers in FileDescriptorProto |
| filePackageField = 2 // package |
| fileMessageField = 4 // message_type |
| fileEnumField = 5 // enum_type |
| fileExtensionField = 7 // extension |
| // field numbers in DescriptorProto |
| messageFieldField = 2 // field |
| messageMessageField = 3 // nested_type |
| messageEnumField = 4 // enum_type |
| messageExtensionField = 6 // extension |
| messageOneofField = 8 // oneof_decl |
| // field numbers in EnumDescriptorProto |
| enumValueField = 2 // value |
| ) |
| for len(path) > 1 { |
| switch d := p.(type) { |
| case *descpb.FileDescriptorProto: |
| switch path[0] { |
| case fileMessageField: |
| p = d.MessageType[path[1]] |
| case fileEnumField: |
| p = d.EnumType[path[1]] |
| default: |
| return nil |
| } |
| case *descpb.DescriptorProto: |
| switch path[0] { |
| case messageFieldField: |
| p = d.Field[path[1]] |
| case messageMessageField: |
| p = d.NestedType[path[1]] |
| case messageEnumField: |
| p = d.EnumType[path[1]] |
| default: |
| return nil |
| } |
| case *descpb.EnumDescriptorProto: |
| switch path[0] { |
| case enumValueField: |
| p = d.Value[path[1]] |
| default: |
| return nil |
| } |
| default: |
| return nil |
| } |
| path = path[2:] |
| } |
| return p |
| } |