python_generator.h

// Protocol Buffers - Google's data interchange format
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// Author: robinson@google.com (Will Robinson)
//
// Generates Python code for a given .proto file.

#ifndef GOOGLE_PROTOBUF_COMPILER_PYTHON_GENERATOR_H__
#define GOOGLE_PROTOBUF_COMPILER_PYTHON_GENERATOR_H__

#include <string>

#include <google/protobuf/compiler/code_generator.h>
#include <google/protobuf/stubs/mutex.h>

#include <google/protobuf/port_def.inc>

namespace google {
namespace protobuf {

class Descriptor;
class EnumDescriptor;
class EnumValueDescriptor;
class FieldDescriptor;
class OneofDescriptor;
class ServiceDescriptor;

namespace io {
class Printer;
}

namespace compiler {
namespace python {

// CodeGenerator implementation for generated Python protocol buffer classes.
// If you create your own protocol compiler binary and you want it to support
// Python output, you can do so by registering an instance of this
// CodeGenerator with the CommandLineInterface in your main() function.
class PROTOC_EXPORT Generator : public CodeGenerator {
 public:
  Generator();
  virtual ~Generator();

  // CodeGenerator methods.
  bool Generate(const FileDescriptor* file, const std::string& parameter,
                GeneratorContext* generator_context,
                std::string* error) const override;

  uint64 GetSupportedFeatures() const override;

 private:
  void PrintImports() const;
  void PrintFileDescriptor() const;
  void PrintTopLevelEnums() const;
  void PrintAllNestedEnumsInFile() const;
  void PrintNestedEnums(const Descriptor& descriptor) const;
  void PrintEnum(const EnumDescriptor& enum_descriptor) const;

  void PrintTopLevelExtensions() const;

  void PrintFieldDescriptor(const FieldDescriptor& field,
                            bool is_extension) const;
  void PrintFieldDescriptorsInDescriptor(
      const Descriptor& message_descriptor, bool is_extension,
      const std::string& list_variable_name, int (Descriptor::*CountFn)() const,
      const FieldDescriptor* (Descriptor::*GetterFn)(int)const) const;
  void PrintFieldsInDescriptor(const Descriptor& message_descriptor) const;
  void PrintExtensionsInDescriptor(const Descriptor& message_descriptor) const;
  void PrintMessageDescriptors() const;
  void PrintDescriptor(const Descriptor& message_descriptor) const;
  void PrintNestedDescriptors(const Descriptor& containing_descriptor) const;

  void PrintMessages() const;
  void PrintMessage(const Descriptor& message_descriptor,
                    const std::string& prefix,
                    std::vector<std::string>* to_register,
                    bool is_nested) const;
  void PrintNestedMessages(const Descriptor& containing_descriptor,
                           const std::string& prefix,
                           std::vector<std::string>* to_register) const;

  void FixForeignFieldsInDescriptors() const;
  void FixForeignFieldsInDescriptor(
      const Descriptor& descriptor,
      const Descriptor* containing_descriptor) const;
  void FixForeignFieldsInField(const Descriptor* containing_type,
                               const FieldDescriptor& field,
                               const std::string& python_dict_name) const;
  void AddMessageToFileDescriptor(const Descriptor& descriptor) const;
  void AddEnumToFileDescriptor(const EnumDescriptor& descriptor) const;
  void AddExtensionToFileDescriptor(const FieldDescriptor& descriptor) const;
  void AddServiceToFileDescriptor(const ServiceDescriptor& descriptor) const;
  std::string FieldReferencingExpression(
      const Descriptor* containing_type, const FieldDescriptor& field,
      const std::string& python_dict_name) const;
  template <typename DescriptorT>
  void FixContainingTypeInDescriptor(
      const DescriptorT& descriptor,
      const Descriptor* containing_descriptor) const;

  void FixForeignFieldsInExtensions() const;
  void FixForeignFieldsInExtension(
      const FieldDescriptor& extension_field) const;
  void FixForeignFieldsInNestedExtensions(const Descriptor& descriptor) const;

  void PrintServices() const;
  void PrintServiceDescriptors() const;
  void PrintServiceDescriptor(const ServiceDescriptor& descriptor) const;
  void PrintServiceClass(const ServiceDescriptor& descriptor) const;
  void PrintServiceStub(const ServiceDescriptor& descriptor) const;
  void PrintDescriptorKeyAndModuleName(
      const ServiceDescriptor& descriptor) const;

  void PrintEnumValueDescriptor(const EnumValueDescriptor& descriptor) const;
  std::string OptionsValue(const std::string& serialized_options) const;
  bool GeneratingDescriptorProto() const;

  template <typename DescriptorT>
  std::string ModuleLevelDescriptorName(const DescriptorT& descriptor) const;
  std::string ModuleLevelMessageName(const Descriptor& descriptor) const;
  std::string ModuleLevelServiceDescriptorName(
      const ServiceDescriptor& descriptor) const;

  template <typename DescriptorT, typename DescriptorProtoT>
  void PrintSerializedPbInterval(const DescriptorT& descriptor,
                                 DescriptorProtoT& proto) const;

  void FixAllDescriptorOptions() const;
  void FixOptionsForField(const FieldDescriptor& field) const;
  void FixOptionsForOneof(const OneofDescriptor& oneof) const;
  void FixOptionsForEnum(const EnumDescriptor& descriptor) const;
  void FixOptionsForMessage(const Descriptor& descriptor) const;

  void CopyPublicDependenciesAliases(const std::string& copy_from,
                                     const FileDescriptor* file) const;

  // Very coarse-grained lock to ensure that Generate() is reentrant.
  // Guards file_, printer_ and file_descriptor_serialized_.
  mutable Mutex mutex_;
  mutable const FileDescriptor* file_;  // Set in Generate().  Under mutex_.
  mutable std::string file_descriptor_serialized_;
  mutable io::Printer* printer_;  // Set in Generate().  Under mutex_.
  mutable bool pure_python_workable_;

  GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(Generator);
};

}  // namespace python
}  // namespace compiler
}  // namespace protobuf
}  // namespace google

#include <google/protobuf/port_undef.inc>

#endif  // GOOGLE_PROTOBUF_COMPILER_PYTHON_GENERATOR_H__