google.protobuf.descriptor¶

Descriptors essentially contain exactly the information found in a .proto file, in types that make this information accessible in Python.

class google.protobuf.descriptor.Descriptor(name, full_name, filename, containing_type, fields, nested_types, enum_types, extensions, options=None, serialized_options=None, is_extendable=True, extension_ranges=None, oneofs=None, file=None, serialized_start=None, serialized_end=None, syntax=None, create_key=None)¶

Descriptor for a protocol message type.

name¶

Name of this protocol message type.

Type:: str

full_name¶

Fully-qualified name of this protocol message type, which will include protocol “package” name and the name of any enclosing types.

Type:: str

containing_type¶

Reference to the descriptor of the type containing us, or None if this is top-level.

Type:: Descriptor

fields¶

Field descriptors for all fields in this type.

Type:: list[FieldDescriptor]

fields_by_number¶

Same FieldDescriptor objects as in fields, but indexed by “number” attribute in each FieldDescriptor.

Type:: dict(int, FieldDescriptor)

fields_by_name¶

Same FieldDescriptor objects as in fields, but indexed by “name” attribute in each FieldDescriptor.

Type:: dict(str, FieldDescriptor)

nested_types¶

Descriptor references for all protocol message types nested within this one.

Type:: list[Descriptor]

nested_types_by_name¶

Same Descriptor objects as in nested_types, but indexed by “name” attribute in each Descriptor.

Type:: dict(str, Descriptor)

enum_types¶

EnumDescriptor references for all enums contained within this type.

Type:: list[EnumDescriptor]

enum_types_by_name¶

Same EnumDescriptor objects as in enum_types, but indexed by “name” attribute in each EnumDescriptor.

Type:: dict(str, EnumDescriptor)

enum_values_by_name¶

Dict mapping from enum value name to EnumValueDescriptor for that value.

Type:: dict(str, EnumValueDescriptor)

extensions¶

All extensions defined directly within this message type (NOT within a nested type).

Type:: list[FieldDescriptor]

extensions_by_name¶

Same FieldDescriptor objects as extensions, but indexed by “name” attribute of each FieldDescriptor.

Type:: dict(str, FieldDescriptor)

is_extendable¶

Does this type define any extension ranges?

Type:: bool

oneofs¶

The list of descriptors for oneof fields in this message.

Type:: list[OneofDescriptor]

oneofs_by_name¶

Same objects as in oneofs, but indexed by “name” attribute.

Type:: dict(str, OneofDescriptor)

file¶

Reference to file descriptor.

Type:: FileDescriptor

CopyToProto(proto)¶

Copies this to a descriptor_pb2.DescriptorProto.

Parameters:: proto – An empty descriptor_pb2.DescriptorProto.

EnumValueName(enum, value)¶

Returns the string name of an enum value.

This is just a small helper method to simplify a common operation.

Parameters:

enum – string name of the Enum.
value – int, value of the enum.

Returns:

string name of the enum value.

Raises:

KeyError if either the Enum doesn't exist or the value is not a valid – value for the enum.

GetOptions()¶

Retrieves descriptor options.

This method returns the options set or creates the default options for the descriptor.

property fields_by_camelcase_name¶: Same FieldDescriptor objects as in fields, but indexed by FieldDescriptor.camelcase_name.

class google.protobuf.descriptor.DescriptorBase(options, serialized_options, options_class_name)¶

Descriptors base class.

This class is the base of all descriptor classes. It provides common options related functionality.

has_options¶: True if the descriptor has non-default options. Usually it is not necessary to read this – just call GetOptions() which will happily return the default instance. However, it’s sometimes useful for efficiency, and also useful inside the protobuf implementation to avoid some bootstrapping issues.

GetOptions()¶

Retrieves descriptor options.

This method returns the options set or creates the default options for the descriptor.

class google.protobuf.descriptor.EnumDescriptor(name, full_name, filename, values, containing_type=None, options=None, serialized_options=None, file=None, serialized_start=None, serialized_end=None, create_key=None)¶

Descriptor for an enum defined in a .proto file.

name¶

Name of the enum type.

Type:: str

full_name¶

Full name of the type, including package name and any enclosing type(s).

Type:: str

values¶

List of the values in this enum.

Type:: list[EnumValueDescriptor]

values_by_name¶

Same as values, but indexed by the “name” field of each EnumValueDescriptor.

Type:: dict(str, EnumValueDescriptor)

values_by_number¶

Same as values, but indexed by the “number” field of each EnumValueDescriptor.

Type:: dict(int, EnumValueDescriptor)

containing_type¶

Descriptor of the immediate containing type of this enum, or None if this is an enum defined at the top level in a .proto file. Set by Descriptor’s constructor if we’re passed into one.

Type:: Descriptor

file¶

Reference to file descriptor.

Type:: FileDescriptor

options¶

Enum options message or None to use default enum options.

Type:: descriptor_pb2.EnumOptions

CopyToProto(proto)¶

Copies this to a descriptor_pb2.EnumDescriptorProto.

Parameters:: proto (descriptor_pb2.EnumDescriptorProto) – An empty descriptor proto.

GetOptions()¶

Retrieves descriptor options.

This method returns the options set or creates the default options for the descriptor.

class google.protobuf.descriptor.EnumValueDescriptor(name, index, number, type=None, options=None, serialized_options=None, create_key=None)¶

Descriptor for a single value within an enum.

name¶

Name of this value.

Type:: str

index¶

Dense, 0-indexed index giving the order that this value appears textually within its enum in the .proto file.

Type:: int

number¶

Actual number assigned to this enum value.

Type:: int

type¶

EnumDescriptor to which this value belongs. Set by EnumDescriptor’s constructor if we’re passed into one.

Type:: EnumDescriptor

options¶

Enum value options message or None to use default enum value options options.

Type:: descriptor_pb2.EnumValueOptions

GetOptions()¶

Retrieves descriptor options.

This method returns the options set or creates the default options for the descriptor.

exception google.protobuf.descriptor.Error¶

Base error for this module.

args¶

with_traceback()¶: Exception.with_traceback(tb) – set self.__traceback__ to tb and return self.

class google.protobuf.descriptor.FieldDescriptor(name, full_name, index, number, type, cpp_type, label, default_value, message_type, enum_type, containing_type, is_extension, extension_scope, options=None, serialized_options=None, has_default_value=True, containing_oneof=None, json_name=None, file=None, create_key=None)¶

Descriptor for a single field in a .proto file.

name¶

Name of this field, exactly as it appears in .proto.

Type:: str

full_name¶

Name of this field, including containing scope. This is particularly relevant for extensions.

Type:: str

index¶

Dense, 0-indexed index giving the order that this field textually appears within its message in the .proto file.

Type:: int

number¶

Tag number declared for this field in the .proto file.

Type:: int

type¶

(One of the TYPE_* constants below) Declared type.

Type:: int

cpp_type¶

(One of the CPPTYPE_* constants below) C++ type used to represent this field.

Type:: int

label¶

(One of the LABEL_* constants below) Tells whether this field is optional, required, or repeated.

Type:: int

has_default_value¶

True if this field has a default value defined, otherwise false.

Type:: bool

default_value¶

Default value of this field. Only meaningful for non-repeated scalar fields. Repeated fields should always set this to [], and non-repeated composite fields should always set this to None.

Type:: Varies

containing_type¶

Descriptor of the protocol message type that contains this field. Set by the Descriptor constructor if we’re passed into one. Somewhat confusingly, for extension fields, this is the descriptor of the EXTENDED message, not the descriptor of the message containing this field. (See is_extension and extension_scope below).

Type:: Descriptor

message_type¶

If a composite field, a descriptor of the message type contained in this field. Otherwise, this is None.

Type:: Descriptor

enum_type¶

If this field contains an enum, a descriptor of that enum. Otherwise, this is None.

Type:: EnumDescriptor

is_extension¶: True iff this describes an extension field.

extension_scope¶

Only meaningful if is_extension is True. Gives the message that immediately contains this extension field. Will be None iff we’re a top-level (file-level) extension field.

Type:: Descriptor

options¶

Protocol message field options or None to use default field options.

Type:: descriptor_pb2.FieldOptions

containing_oneof¶

If the field is a member of a oneof union, contains its descriptor. Otherwise, None.

Type:: OneofDescriptor

file¶

Reference to file descriptor.

Type:: FileDescriptor

CPPTYPE_BOOL = 7¶

CPPTYPE_DOUBLE = 5¶

CPPTYPE_ENUM = 8¶

CPPTYPE_FLOAT = 6¶

CPPTYPE_INT32 = 1¶

CPPTYPE_INT64 = 2¶

CPPTYPE_MESSAGE = 10¶

CPPTYPE_STRING = 9¶

CPPTYPE_UINT32 = 3¶

CPPTYPE_UINT64 = 4¶

FIRST_RESERVED_FIELD_NUMBER = 19000¶

GetOptions()¶

Retrieves descriptor options.

This method returns the options set or creates the default options for the descriptor.

LABEL_OPTIONAL = 1¶

LABEL_REPEATED = 3¶

LABEL_REQUIRED = 2¶

LAST_RESERVED_FIELD_NUMBER = 19999¶

MAX_CPPTYPE = 10¶

MAX_FIELD_NUMBER = 536870911¶

MAX_LABEL = 3¶

MAX_TYPE = 18¶

static ProtoTypeToCppProtoType(proto_type)¶

Converts from a Python proto type to a C++ Proto Type.

The Python ProtocolBuffer classes specify both the ‘Python’ datatype and the ‘C++’ datatype - and they’re not the same. This helper method should translate from one to another.

Parameters:: proto_type – the Python proto type (descriptor.FieldDescriptor.TYPE_*)
Returns:: descriptor.FieldDescriptor.CPPTYPE_*, the C++ type.
Return type:: int
Raises:: TypeTransformationError – when the Python proto type isn’t known.

TYPE_BOOL = 8¶

TYPE_BYTES = 12¶

TYPE_DOUBLE = 1¶

TYPE_ENUM = 14¶

TYPE_FIXED32 = 7¶

TYPE_FIXED64 = 6¶

TYPE_FLOAT = 2¶

TYPE_GROUP = 10¶

TYPE_INT32 = 5¶

TYPE_INT64 = 3¶

TYPE_MESSAGE = 11¶

TYPE_SFIXED32 = 15¶

TYPE_SFIXED64 = 16¶

TYPE_SINT32 = 17¶

TYPE_SINT64 = 18¶

TYPE_STRING = 9¶

TYPE_UINT32 = 13¶

TYPE_UINT64 = 4¶

property camelcase_name¶

Camelcase name of this field.

Returns:: the name in CamelCase.
Return type:: str

property has_presence¶

Whether the field distinguishes between unpopulated and default values.

Raises:: RuntimeError – singular field that is not linked with message nor file.

class google.protobuf.descriptor.FileDescriptor(name, package, options=None, serialized_options=None, serialized_pb=None, dependencies=None, public_dependencies=None, syntax=None, pool=None, create_key=None)¶

Descriptor for a file. Mimics the descriptor_pb2.FileDescriptorProto.

Note that enum_types_by_name, extensions_by_name, and dependencies fields are only set by the google.protobuf.message_factory module, and not by the generated proto code.

name¶

Name of file, relative to root of source tree.

Type:: str

package¶

Name of the package

Type:: str

syntax¶

string indicating syntax of the file (can be “proto2” or “proto3”)

Type:: str

serialized_pb¶

Byte string of serialized descriptor_pb2.FileDescriptorProto.

Type:: bytes

dependencies¶

List of other FileDescriptor objects this FileDescriptor depends on.

Type:: list[FileDescriptor]

public_dependencies¶

A subset of dependencies, which were declared as “public”.

Type:: list[FileDescriptor]

message_types_by_name¶

Mapping from message names to their Descriptor.

Type:: dict(str, Descriptor)

enum_types_by_name¶

Mapping from enum names to their EnumDescriptor.

Type:: dict(str, EnumDescriptor)

extensions_by_name¶

Mapping from extension names declared at file scope to their FieldDescriptor.

Type:: dict(str, FieldDescriptor)

services_by_name¶

Mapping from services’ names to their ServiceDescriptor.

Type:: dict(str, ServiceDescriptor)

pool¶

The pool this descriptor belongs to. When not passed to the constructor, the global default pool is used.

Type:: DescriptorPool

CopyToProto(proto)¶

Copies this to a descriptor_pb2.FileDescriptorProto.

Parameters:: proto – An empty descriptor_pb2.FileDescriptorProto.

GetOptions()¶

Retrieves descriptor options.

This method returns the options set or creates the default options for the descriptor.

google.protobuf.descriptor.MakeDescriptor(desc_proto, package='', build_file_if_cpp=True, syntax=None)¶

Make a protobuf Descriptor given a DescriptorProto protobuf.

Handles nested descriptors. Note that this is limited to the scope of defining a message inside of another message. Composite fields can currently only be resolved if the message is defined in the same scope as the field.

Parameters:

desc_proto – The descriptor_pb2.DescriptorProto protobuf message.
package – Optional package name for the new message Descriptor (string).
build_file_if_cpp – Update the C++ descriptor pool if api matches. Set to False on recursion, so no duplicates are created.
syntax – The syntax/semantics that should be used. Set to “proto3” to get proto3 field presence semantics.

Returns:

A Descriptor for protobuf messages.

class google.protobuf.descriptor.MethodDescriptor(name, full_name, index, containing_service, input_type, output_type, client_streaming=False, server_streaming=False, options=None, serialized_options=None, create_key=None)¶

Descriptor for a method in a service.

name¶

Name of the method within the service.

Type:: str

full_name¶

Full name of method.

Type:: str

index¶

0-indexed index of the method inside the service.

Type:: int

containing_service¶

The service that contains this method.

Type:: ServiceDescriptor

input_type¶

The descriptor of the message that this method accepts.

Type:: Descriptor

output_type¶

The descriptor of the message that this method returns.

Type:: Descriptor

client_streaming¶

Whether this method uses client streaming.

Type:: bool

server_streaming¶

Whether this method uses server streaming.

Type:: bool

options¶

Method options message, or None to use default method options.

Type:: descriptor_pb2.MethodOptions or None

CopyToProto(proto)¶

Copies this to a descriptor_pb2.MethodDescriptorProto.

Parameters:: proto (descriptor_pb2.MethodDescriptorProto) – An empty descriptor proto.
Raises:: Error – If self couldn’t be serialized, due to too few constructor arguments.

GetOptions()¶

Retrieves descriptor options.

This method returns the options set or creates the default options for the descriptor.

class google.protobuf.descriptor.OneofDescriptor(name, full_name, index, containing_type, fields, options=None, serialized_options=None, create_key=None)¶

Descriptor for a oneof field.

name¶

Name of the oneof field.

Type:: str

full_name¶

Full name of the oneof field, including package name.

Type:: str

index¶

0-based index giving the order of the oneof field inside its containing type.

Type:: int

containing_type¶

Descriptor of the protocol message type that contains this field. Set by the Descriptor constructor if we’re passed into one.

Type:: Descriptor

fields¶

The list of field descriptors this oneof can contain.

Type:: list[FieldDescriptor]

GetOptions()¶

Retrieves descriptor options.

This method returns the options set or creates the default options for the descriptor.

class google.protobuf.descriptor.ServiceDescriptor(name, full_name, index, methods, options=None, serialized_options=None, file=None, serialized_start=None, serialized_end=None, create_key=None)¶

Descriptor for a service.

name¶

Name of the service.

Type:: str

full_name¶

Full name of the service, including package name.

Type:: str

index¶

0-indexed index giving the order that this services definition appears within the .proto file.

Type:: int

methods¶

List of methods provided by this service.

Type:: list[MethodDescriptor]

methods_by_name¶

Same MethodDescriptor objects as in methods_by_name, but indexed by “name” attribute in each MethodDescriptor.

Type:: dict(str, MethodDescriptor)

options¶

Service options message or None to use default service options.

Type:: descriptor_pb2.ServiceOptions

file¶

Reference to file info.

Type:: FileDescriptor

CopyToProto(proto)¶

Copies this to a descriptor_pb2.ServiceDescriptorProto.

Parameters:: proto (descriptor_pb2.ServiceDescriptorProto) – An empty descriptor proto.

FindMethodByName(name)¶

Searches for the specified method, and returns its descriptor.

Parameters:: name (str) – Name of the method.
Returns:: the descriptor for the requested method, if found.
Return type:: MethodDescriptor or None

GetOptions()¶

Retrieves descriptor options.

This method returns the options set or creates the default options for the descriptor.

exception google.protobuf.descriptor.TypeTransformationError¶

Error transforming between python proto type and corresponding C++ type.

args¶

with_traceback()¶: Exception.with_traceback(tb) – set self.__traceback__ to tb and return self.

google.protobuf.descriptor¶

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