| #!/usr/bin/env python3 |
| # Copyright 2016 The Chromium Authors |
| # Use of this source code is governed by a BSD-style license that can be |
| # found in the LICENSE file. |
| |
| """protoc plugin to create C++ reader/writer for JSON-encoded protobufs |
| |
| The reader/writer use Chrome's base::Values. |
| """ |
| |
| import os |
| import sys |
| |
| from util import plugin_protos, types, writer |
| |
| |
| class CppConverterWriter(writer.CodeWriter): |
| def WriteProtoFile(self, proto_file, output_dir): |
| err = proto_file.CheckSupported() |
| if err: |
| self.AddError(err) |
| return |
| |
| self.WriteCStyleHeader() |
| |
| self.Output('#include "{output_dir}{generated_pb_h}"', |
| output_dir=output_dir + '/' if output_dir else '', |
| generated_pb_h=proto_file.CppBaseHeader()) |
| self.Output('') |
| |
| # import is not supported |
| assert [] == proto_file.GetDependencies() |
| |
| self.Output('// base dependencies') |
| self.Output('#include "base/values.h"') |
| self.Output('') |
| self.Output('#include <memory>') |
| self.Output('#include <string>') |
| self.Output('#include <utility>') |
| self.Output('') |
| |
| namespaces = proto_file.ProtoNamespaces() + ['json'] |
| for name in namespaces: |
| self.Output('namespace {name} {{', name=name) |
| self.IncreaseIndent() |
| |
| for message in proto_file.GetMessages(): |
| self.WriteMessage(message) |
| |
| # Nothing to do for enums |
| |
| for name in namespaces: |
| self.DecreaseIndent() |
| self.Output('}}') |
| |
| def WriteMessage(self, message): |
| self.Output('class {class_name} {{', |
| class_name=message.CppConverterClassName()) |
| self.Output(' public:') |
| with self.AddIndent(): |
| for nested_class in message.GetMessages(): |
| self.WriteMessage(nested_class) |
| |
| generated_class_name = message.QualifiedTypes().cpp_base |
| # Nothing to write for enums. |
| |
| self.Output( |
| 'static bool ReadFromValue(const base::Value& dict_value, {generated_class_name}* message) {{\n' |
| ' const base::Value::Dict* dict = dict_value.GetIfDict();\n' |
| ' if (!dict) goto error;\n' |
| '', |
| generated_class_name=generated_class_name) |
| |
| with self.AddIndent(): |
| for field_proto in message.GetFields(): |
| self.WriteFieldRead(field_proto) |
| |
| self.Output( |
| ' return true;\n' |
| '\n' |
| 'error:\n' |
| ' return false;\n' |
| '}}\n' |
| '\n' |
| 'static base::Value WriteToValue(const {generated_class_name}& message) {{\n' |
| ' base::Value::Dict dict;\n' |
| '', |
| generated_class_name=generated_class_name) |
| |
| with self.AddIndent(): |
| for field_proto in message.GetFields(): |
| self.FieldWriteToValue(field_proto) |
| |
| self.Output( |
| ' return base::Value(std::move(dict));\n' |
| '', |
| generated_class_name=generated_class_name) |
| self.Output('}}') |
| |
| self.Output('}};') |
| self.Output('') |
| |
| def FieldWriteToValue(self, field): |
| if field.IsRepeated(): |
| self.Output('{{') |
| else: |
| self.Output('if (message.has_{field_name}()) {{\n', field_name=field.name) |
| |
| with self.AddIndent(): |
| if field.IsRepeated(): |
| self.RepeatedMemberFieldWriteToValue(field) |
| else: |
| self.OptionalMemberFieldWriteToValue(field) |
| |
| self.Output('}}') |
| |
| def RepeatedMemberFieldWriteToValue(self, field): |
| if field.IsClassType(): |
| self.Output( |
| 'const auto& repeated_field = message.{field_name}();\n' |
| 'base::Value::List field_list;\n' |
| 'field_list.reserve(repeated_field.size());\n' |
| 'for (const auto& element : repeated_field) {{\n' |
| ' field_list.Append(\n' |
| ' {inner_class_converter}::WriteToValue(element));\n' |
| '}}\n' |
| 'dict.Set("{field_number}", std::move(field_list));\n', |
| field_number=field.JavascriptIndex(), |
| field_name=field.name, |
| inner_class_converter=field.CppConverterType() |
| ) |
| else: |
| self.Output( |
| 'const auto& repeated_field = message.{field_name}();\n' |
| 'base::Value::List field_list;\n' |
| 'field_list.reserve(repeated_field.size());\n' |
| 'for (const auto& element : repeated_field) {{\n' |
| ' field_list.Append(element);\n' |
| '}}\n' |
| 'dict.Set("{field_number}", std::move(field_list));\n', |
| field_number=field.JavascriptIndex(), |
| field_name=field.name |
| ) |
| |
| def OptionalMemberFieldWriteToValue(self, field): |
| if field.IsClassType(): |
| self.Output( |
| 'dict.Set("{field_number}",\n' |
| ' {inner_class_converter}::WriteToValue(\n' |
| ' message.{field_name}()));\n', |
| field_number=field.JavascriptIndex(), |
| field_name=field.name, |
| inner_class_converter=field.CppConverterType() |
| ) |
| else: |
| self.Output( |
| 'dict.Set("{field_number}", message.{field_name}());\n', |
| field_number=field.JavascriptIndex(), |
| field_name=field.name, |
| value_type=field.CppValueType() |
| ) |
| |
| def WriteFieldRead(self, field): |
| self.Output('if (const auto* value = dict->Find("{field_number}")) {{', |
| field_number=field.JavascriptIndex()) |
| |
| with self.AddIndent(): |
| if field.IsRepeated(): |
| self.RepeatedMemberFieldRead(field) |
| else: |
| self.OptionalMemberFieldRead(field) |
| |
| self.Output('}}') |
| |
| def RepeatedMemberFieldRead(self, field): |
| self.Output( |
| 'if (!value->is_list()) {{\n' |
| ' goto error;\n' |
| '}}\n' |
| 'for (const auto& element : value->GetList()) {{\n' |
| ) |
| |
| with self.AddIndent(): |
| if field.IsClassType(): |
| self.Output( |
| 'if (!{inner_class_parser}::ReadFromValue(element, message->add_{field_name}())) {{\n' |
| ' goto error;\n' |
| '}}\n', |
| field_name=field.name, |
| inner_class_parser=field.CppConverterType() |
| ) |
| else: |
| self.Output( |
| 'if (!{predicate}) {{\n' |
| ' goto error;\n' |
| '}}\n' |
| 'message->add_{field_name}(element.Get{value_type}());\n', |
| field_name=field.name, |
| value_type=field.CppValueType(), |
| predicate=field.CppValuePredicate('element') |
| ) |
| |
| self.Output('}}\n') |
| |
| def OptionalMemberFieldRead(self, field): |
| if field.IsClassType(): |
| self.Output( |
| 'if (!{inner_class_parser}::ReadFromValue(*value, message->mutable_{field_name}())) {{\n' |
| ' goto error;\n' |
| '}}\n', |
| field_number=field.JavascriptIndex(), |
| field_name=field.name, |
| inner_class_parser=field.CppConverterType() |
| ) |
| else: |
| self.Output( |
| 'if (!{predicate}) {{\n' |
| ' goto error;\n' |
| '}}\n' |
| 'message->set_{field_name}(value->Get{value_type}());\n', |
| field_name=field.name, |
| value_type=field.CppValueType(), |
| predicate=field.CppValuePredicate('(*value)') |
| ) |
| |
| |
| def Indented(s, indent=2): |
| return '\n'.join((' ' * indent) + p for p in s.rstrip('\n').split('\n')) |
| |
| |
| def SetBinaryStdio(): |
| import platform |
| if platform.system() == 'Windows': |
| import msvcrt |
| msvcrt.setmode(sys.stdin.fileno(), os.O_BINARY) |
| msvcrt.setmode(sys.stdout.fileno(), os.O_BINARY) |
| |
| |
| def ReadRequestFromStdin(): |
| stream = sys.stdin if sys.version_info[0] < 3 else sys.stdin.buffer |
| data = stream.read() |
| return plugin_protos.PluginRequestFromString(data) |
| |
| |
| def main(): |
| SetBinaryStdio() |
| request = ReadRequestFromStdin() |
| response = plugin_protos.PluginResponse() |
| |
| output_dir = request.GetArgs().get('output_dir', '') |
| |
| for proto_file in request.GetAllFiles(): |
| types.RegisterProtoFile(proto_file) |
| |
| cppwriter = CppConverterWriter() |
| cppwriter.WriteProtoFile(proto_file, output_dir) |
| |
| converter_filename = proto_file.CppConverterFilename() |
| if output_dir: |
| converter_filename = os.path.join(output_dir, |
| os.path.split(converter_filename)[1]) |
| |
| response.AddFileWithContent(converter_filename, cppwriter.GetValue()) |
| if cppwriter.GetErrors(): |
| response.AddError('\n'.join(cppwriter.GetErrors())) |
| |
| response.WriteToStdout() |
| |
| |
| if __name__ == '__main__': |
| main() |
