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Diffstat (limited to 'generator/google/protobuf/json_format.py')
| -rw-r--r-- | generator/google/protobuf/json_format.py | 664 |
1 files changed, 664 insertions, 0 deletions
diff --git a/generator/google/protobuf/json_format.py b/generator/google/protobuf/json_format.py new file mode 100644 index 0000000..bb6a199 --- /dev/null +++ b/generator/google/protobuf/json_format.py @@ -0,0 +1,664 @@ +# Protocol Buffers - Google's data interchange format +# Copyright 2008 Google Inc. All rights reserved. +# https://developers.google.com/protocol-buffers/ +# +# Redistribution and use in source and binary forms, with or without +# modification, are permitted provided that the following conditions are +# met: +# +# * Redistributions of source code must retain the above copyright +# notice, this list of conditions and the following disclaimer. +# * Redistributions in binary form must reproduce the above +# copyright notice, this list of conditions and the following disclaimer +# in the documentation and/or other materials provided with the +# distribution. +# * Neither the name of Google Inc. nor the names of its +# contributors may be used to endorse or promote products derived from +# this software without specific prior written permission. +# +# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +"""Contains routines for printing protocol messages in JSON format. + +Simple usage example: + + # Create a proto object and serialize it to a json format string. + message = my_proto_pb2.MyMessage(foo='bar') + json_string = json_format.MessageToJson(message) + + # Parse a json format string to proto object. + message = json_format.Parse(json_string, my_proto_pb2.MyMessage()) +""" + +__author__ = 'jieluo@google.com (Jie Luo)' + +try: + from collections import OrderedDict +except ImportError: + from ordereddict import OrderedDict #PY26 +import base64 +import json +import math +import re +import six +import sys + +from operator import methodcaller +from google.protobuf import descriptor +from google.protobuf import symbol_database + +_TIMESTAMPFOMAT = '%Y-%m-%dT%H:%M:%S' +_INT_TYPES = frozenset([descriptor.FieldDescriptor.CPPTYPE_INT32, + descriptor.FieldDescriptor.CPPTYPE_UINT32, + descriptor.FieldDescriptor.CPPTYPE_INT64, + descriptor.FieldDescriptor.CPPTYPE_UINT64]) +_INT64_TYPES = frozenset([descriptor.FieldDescriptor.CPPTYPE_INT64, + descriptor.FieldDescriptor.CPPTYPE_UINT64]) +_FLOAT_TYPES = frozenset([descriptor.FieldDescriptor.CPPTYPE_FLOAT, + descriptor.FieldDescriptor.CPPTYPE_DOUBLE]) +_INFINITY = 'Infinity' +_NEG_INFINITY = '-Infinity' +_NAN = 'NaN' + +_UNPAIRED_SURROGATE_PATTERN = re.compile(six.u( + r'[\ud800-\udbff](?![\udc00-\udfff])|(?<![\ud800-\udbff])[\udc00-\udfff]' +)) + +class Error(Exception): + """Top-level module error for json_format.""" + + +class SerializeToJsonError(Error): + """Thrown if serialization to JSON fails.""" + + +class ParseError(Error): + """Thrown in case of parsing error.""" + + +def MessageToJson(message, including_default_value_fields=False): + """Converts protobuf message to JSON format. + + Args: + message: The protocol buffers message instance to serialize. + including_default_value_fields: If True, singular primitive fields, + repeated fields, and map fields will always be serialized. If + False, only serialize non-empty fields. Singular message fields + and oneof fields are not affected by this option. + + Returns: + A string containing the JSON formatted protocol buffer message. + """ + printer = _Printer(including_default_value_fields) + return printer.ToJsonString(message) + + +def _IsMapEntry(field): + return (field.type == descriptor.FieldDescriptor.TYPE_MESSAGE and + field.message_type.has_options and + field.message_type.GetOptions().map_entry) + + +class _Printer(object): + """JSON format printer for protocol message.""" + + def __init__(self, + including_default_value_fields=False): + self.including_default_value_fields = including_default_value_fields + + def ToJsonString(self, message): + js = self._MessageToJsonObject(message) + return json.dumps(js, indent=2) + + def _MessageToJsonObject(self, message): + """Converts message to an object according to Proto3 JSON Specification.""" + message_descriptor = message.DESCRIPTOR + full_name = message_descriptor.full_name + if _IsWrapperMessage(message_descriptor): + return self._WrapperMessageToJsonObject(message) + if full_name in _WKTJSONMETHODS: + return methodcaller(_WKTJSONMETHODS[full_name][0], message)(self) + js = {} + return self._RegularMessageToJsonObject(message, js) + + def _RegularMessageToJsonObject(self, message, js): + """Converts normal message according to Proto3 JSON Specification.""" + fields = message.ListFields() + + try: + for field, value in fields: + name = field.camelcase_name + if _IsMapEntry(field): + # Convert a map field. + v_field = field.message_type.fields_by_name['value'] + js_map = {} + for key in value: + if isinstance(key, bool): + if key: + recorded_key = 'true' + else: + recorded_key = 'false' + else: + recorded_key = key + js_map[recorded_key] = self._FieldToJsonObject( + v_field, value[key]) + js[name] = js_map + elif field.label == descriptor.FieldDescriptor.LABEL_REPEATED: + # Convert a repeated field. + js[name] = [self._FieldToJsonObject(field, k) + for k in value] + else: + js[name] = self._FieldToJsonObject(field, value) + + # Serialize default value if including_default_value_fields is True. + if self.including_default_value_fields: + message_descriptor = message.DESCRIPTOR + for field in message_descriptor.fields: + # Singular message fields and oneof fields will not be affected. + if ((field.label != descriptor.FieldDescriptor.LABEL_REPEATED and + field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_MESSAGE) or + field.containing_oneof): + continue + name = field.camelcase_name + if name in js: + # Skip the field which has been serailized already. + continue + if _IsMapEntry(field): + js[name] = {} + elif field.label == descriptor.FieldDescriptor.LABEL_REPEATED: + js[name] = [] + else: + js[name] = self._FieldToJsonObject(field, field.default_value) + + except ValueError as e: + raise SerializeToJsonError( + 'Failed to serialize {0} field: {1}.'.format(field.name, e)) + + return js + + def _FieldToJsonObject(self, field, value): + """Converts field value according to Proto3 JSON Specification.""" + if field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_MESSAGE: + return self._MessageToJsonObject(value) + elif field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_ENUM: + enum_value = field.enum_type.values_by_number.get(value, None) + if enum_value is not None: + return enum_value.name + else: + raise SerializeToJsonError('Enum field contains an integer value ' + 'which can not mapped to an enum value.') + elif field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_STRING: + if field.type == descriptor.FieldDescriptor.TYPE_BYTES: + # Use base64 Data encoding for bytes + return base64.b64encode(value).decode('utf-8') + else: + return value + elif field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_BOOL: + return bool(value) + elif field.cpp_type in _INT64_TYPES: + return str(value) + elif field.cpp_type in _FLOAT_TYPES: + if math.isinf(value): + if value < 0.0: + return _NEG_INFINITY + else: + return _INFINITY + if math.isnan(value): + return _NAN + return value + + def _AnyMessageToJsonObject(self, message): + """Converts Any message according to Proto3 JSON Specification.""" + if not message.ListFields(): + return {} + # Must print @type first, use OrderedDict instead of {} + js = OrderedDict() + type_url = message.type_url + js['@type'] = type_url + sub_message = _CreateMessageFromTypeUrl(type_url) + sub_message.ParseFromString(message.value) + message_descriptor = sub_message.DESCRIPTOR + full_name = message_descriptor.full_name + if _IsWrapperMessage(message_descriptor): + js['value'] = self._WrapperMessageToJsonObject(sub_message) + return js + if full_name in _WKTJSONMETHODS: + js['value'] = methodcaller(_WKTJSONMETHODS[full_name][0], + sub_message)(self) + return js + return self._RegularMessageToJsonObject(sub_message, js) + + def _GenericMessageToJsonObject(self, message): + """Converts message according to Proto3 JSON Specification.""" + # Duration, Timestamp and FieldMask have ToJsonString method to do the + # convert. Users can also call the method directly. + return message.ToJsonString() + + def _ValueMessageToJsonObject(self, message): + """Converts Value message according to Proto3 JSON Specification.""" + which = message.WhichOneof('kind') + # If the Value message is not set treat as null_value when serialize + # to JSON. The parse back result will be different from original message. + if which is None or which == 'null_value': + return None + if which == 'list_value': + return self._ListValueMessageToJsonObject(message.list_value) + if which == 'struct_value': + value = message.struct_value + else: + value = getattr(message, which) + oneof_descriptor = message.DESCRIPTOR.fields_by_name[which] + return self._FieldToJsonObject(oneof_descriptor, value) + + def _ListValueMessageToJsonObject(self, message): + """Converts ListValue message according to Proto3 JSON Specification.""" + return [self._ValueMessageToJsonObject(value) + for value in message.values] + + def _StructMessageToJsonObject(self, message): + """Converts Struct message according to Proto3 JSON Specification.""" + fields = message.fields + ret = {} + for key in fields: + ret[key] = self._ValueMessageToJsonObject(fields[key]) + return ret + + def _WrapperMessageToJsonObject(self, message): + return self._FieldToJsonObject( + message.DESCRIPTOR.fields_by_name['value'], message.value) + + +def _IsWrapperMessage(message_descriptor): + return message_descriptor.file.name == 'google/protobuf/wrappers.proto' + + +def _DuplicateChecker(js): + result = {} + for name, value in js: + if name in result: + raise ParseError('Failed to load JSON: duplicate key {0}.'.format(name)) + result[name] = value + return result + + +def _CreateMessageFromTypeUrl(type_url): + # TODO(jieluo): Should add a way that users can register the type resolver + # instead of the default one. + db = symbol_database.Default() + type_name = type_url.split('/')[-1] + try: + message_descriptor = db.pool.FindMessageTypeByName(type_name) + except KeyError: + raise TypeError( + 'Can not find message descriptor by type_url: {0}.'.format(type_url)) + message_class = db.GetPrototype(message_descriptor) + return message_class() + + +def Parse(text, message, ignore_unknown_fields=False): + """Parses a JSON representation of a protocol message into a message. + + Args: + text: Message JSON representation. + message: A protocol beffer message to merge into. + ignore_unknown_fields: If True, do not raise errors for unknown fields. + + Returns: + The same message passed as argument. + + Raises:: + ParseError: On JSON parsing problems. + """ + if not isinstance(text, six.text_type): text = text.decode('utf-8') + try: + if sys.version_info < (2, 7): + # object_pair_hook is not supported before python2.7 + js = json.loads(text) + else: + js = json.loads(text, object_pairs_hook=_DuplicateChecker) + except ValueError as e: + raise ParseError('Failed to load JSON: {0}.'.format(str(e))) + parser = _Parser(ignore_unknown_fields) + parser.ConvertMessage(js, message) + return message + + +_INT_OR_FLOAT = six.integer_types + (float,) + + +class _Parser(object): + """JSON format parser for protocol message.""" + + def __init__(self, + ignore_unknown_fields): + self.ignore_unknown_fields = ignore_unknown_fields + + def ConvertMessage(self, value, message): + """Convert a JSON object into a message. + + Args: + value: A JSON object. + message: A WKT or regular protocol message to record the data. + + Raises: + ParseError: In case of convert problems. + """ + message_descriptor = message.DESCRIPTOR + full_name = message_descriptor.full_name + if _IsWrapperMessage(message_descriptor): + self._ConvertWrapperMessage(value, message) + elif full_name in _WKTJSONMETHODS: + methodcaller(_WKTJSONMETHODS[full_name][1], value, message)(self) + else: + self._ConvertFieldValuePair(value, message) + + def _ConvertFieldValuePair(self, js, message): + """Convert field value pairs into regular message. + + Args: + js: A JSON object to convert the field value pairs. + message: A regular protocol message to record the data. + + Raises: + ParseError: In case of problems converting. + """ + names = [] + message_descriptor = message.DESCRIPTOR + for name in js: + try: + field = message_descriptor.fields_by_camelcase_name.get(name, None) + if not field: + if self.ignore_unknown_fields: + continue + raise ParseError( + 'Message type "{0}" has no field named "{1}".'.format( + message_descriptor.full_name, name)) + if name in names: + raise ParseError('Message type "{0}" should not have multiple ' + '"{1}" fields.'.format( + message.DESCRIPTOR.full_name, name)) + names.append(name) + # Check no other oneof field is parsed. + if field.containing_oneof is not None: + oneof_name = field.containing_oneof.name + if oneof_name in names: + raise ParseError('Message type "{0}" should not have multiple ' + '"{1}" oneof fields.'.format( + message.DESCRIPTOR.full_name, oneof_name)) + names.append(oneof_name) + + value = js[name] + if value is None: + message.ClearField(field.name) + continue + + # Parse field value. + if _IsMapEntry(field): + message.ClearField(field.name) + self._ConvertMapFieldValue(value, message, field) + elif field.label == descriptor.FieldDescriptor.LABEL_REPEATED: + message.ClearField(field.name) + if not isinstance(value, list): + raise ParseError('repeated field {0} must be in [] which is ' + '{1}.'.format(name, value)) + if field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_MESSAGE: + # Repeated message field. + for item in value: + sub_message = getattr(message, field.name).add() + # None is a null_value in Value. + if (item is None and + sub_message.DESCRIPTOR.full_name != 'google.protobuf.Value'): + raise ParseError('null is not allowed to be used as an element' + ' in a repeated field.') + self.ConvertMessage(item, sub_message) + else: + # Repeated scalar field. + for item in value: + if item is None: + raise ParseError('null is not allowed to be used as an element' + ' in a repeated field.') + getattr(message, field.name).append( + _ConvertScalarFieldValue(item, field)) + elif field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_MESSAGE: + sub_message = getattr(message, field.name) + self.ConvertMessage(value, sub_message) + else: + setattr(message, field.name, _ConvertScalarFieldValue(value, field)) + except ParseError as e: + if field and field.containing_oneof is None: + raise ParseError('Failed to parse {0} field: {1}'.format(name, e)) + else: + raise ParseError(str(e)) + except ValueError as e: + raise ParseError('Failed to parse {0} field: {1}.'.format(name, e)) + except TypeError as e: + raise ParseError('Failed to parse {0} field: {1}.'.format(name, e)) + + def _ConvertAnyMessage(self, value, message): + """Convert a JSON representation into Any message.""" + if isinstance(value, dict) and not value: + return + try: + type_url = value['@type'] + except KeyError: + raise ParseError('@type is missing when parsing any message.') + + sub_message = _CreateMessageFromTypeUrl(type_url) + message_descriptor = sub_message.DESCRIPTOR + full_name = message_descriptor.full_name + if _IsWrapperMessage(message_descriptor): + self._ConvertWrapperMessage(value['value'], sub_message) + elif full_name in _WKTJSONMETHODS: + methodcaller( + _WKTJSONMETHODS[full_name][1], value['value'], sub_message)(self) + else: + del value['@type'] + self._ConvertFieldValuePair(value, sub_message) + # Sets Any message + message.value = sub_message.SerializeToString() + message.type_url = type_url + + def _ConvertGenericMessage(self, value, message): + """Convert a JSON representation into message with FromJsonString.""" + # Durantion, Timestamp, FieldMask have FromJsonString method to do the + # convert. Users can also call the method directly. + message.FromJsonString(value) + + def _ConvertValueMessage(self, value, message): + """Convert a JSON representation into Value message.""" + if isinstance(value, dict): + self._ConvertStructMessage(value, message.struct_value) + elif isinstance(value, list): + self. _ConvertListValueMessage(value, message.list_value) + elif value is None: + message.null_value = 0 + elif isinstance(value, bool): + message.bool_value = value + elif isinstance(value, six.string_types): + message.string_value = value + elif isinstance(value, _INT_OR_FLOAT): + message.number_value = value + else: + raise ParseError('Unexpected type for Value message.') + + def _ConvertListValueMessage(self, value, message): + """Convert a JSON representation into ListValue message.""" + if not isinstance(value, list): + raise ParseError( + 'ListValue must be in [] which is {0}.'.format(value)) + message.ClearField('values') + for item in value: + self._ConvertValueMessage(item, message.values.add()) + + def _ConvertStructMessage(self, value, message): + """Convert a JSON representation into Struct message.""" + if not isinstance(value, dict): + raise ParseError( + 'Struct must be in a dict which is {0}.'.format(value)) + for key in value: + self._ConvertValueMessage(value[key], message.fields[key]) + return + + def _ConvertWrapperMessage(self, value, message): + """Convert a JSON representation into Wrapper message.""" + field = message.DESCRIPTOR.fields_by_name['value'] + setattr(message, 'value', _ConvertScalarFieldValue(value, field)) + + def _ConvertMapFieldValue(self, value, message, field): + """Convert map field value for a message map field. + + Args: + value: A JSON object to convert the map field value. + message: A protocol message to record the converted data. + field: The descriptor of the map field to be converted. + + Raises: + ParseError: In case of convert problems. + """ + if not isinstance(value, dict): + raise ParseError( + 'Map field {0} must be in a dict which is {1}.'.format( + field.name, value)) + key_field = field.message_type.fields_by_name['key'] + value_field = field.message_type.fields_by_name['value'] + for key in value: + key_value = _ConvertScalarFieldValue(key, key_field, True) + if value_field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_MESSAGE: + self.ConvertMessage(value[key], getattr( + message, field.name)[key_value]) + else: + getattr(message, field.name)[key_value] = _ConvertScalarFieldValue( + value[key], value_field) + + +def _ConvertScalarFieldValue(value, field, require_str=False): + """Convert a single scalar field value. + + Args: + value: A scalar value to convert the scalar field value. + field: The descriptor of the field to convert. + require_str: If True, the field value must be a str. + + Returns: + The converted scalar field value + + Raises: + ParseError: In case of convert problems. + """ + if field.cpp_type in _INT_TYPES: + return _ConvertInteger(value) + elif field.cpp_type in _FLOAT_TYPES: + return _ConvertFloat(value) + elif field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_BOOL: + return _ConvertBool(value, require_str) + elif field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_STRING: + if field.type == descriptor.FieldDescriptor.TYPE_BYTES: + return base64.b64decode(value) + else: + # Checking for unpaired surrogates appears to be unreliable, + # depending on the specific Python version, so we check manually. + if _UNPAIRED_SURROGATE_PATTERN.search(value): + raise ParseError('Unpaired surrogate') + return value + elif field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_ENUM: + # Convert an enum value. + enum_value = field.enum_type.values_by_name.get(value, None) + if enum_value is None: + raise ParseError( + 'Enum value must be a string literal with double quotes. ' + 'Type "{0}" has no value named {1}.'.format( + field.enum_type.full_name, value)) + return enum_value.number + + +def _ConvertInteger(value): + """Convert an integer. + + Args: + value: A scalar value to convert. + + Returns: + The integer value. + + Raises: + ParseError: If an integer couldn't be consumed. + """ + if isinstance(value, float): + raise ParseError('Couldn\'t parse integer: {0}.'.format(value)) + + if isinstance(value, six.text_type) and value.find(' ') != -1: + raise ParseError('Couldn\'t parse integer: "{0}".'.format(value)) + + return int(value) + + +def _ConvertFloat(value): + """Convert an floating point number.""" + if value == 'nan': + raise ParseError('Couldn\'t parse float "nan", use "NaN" instead.') + try: + # Assume Python compatible syntax. + return float(value) + except ValueError: + # Check alternative spellings. + if value == _NEG_INFINITY: + return float('-inf') + elif value == _INFINITY: + return float('inf') + elif value == _NAN: + return float('nan') + else: + raise ParseError('Couldn\'t parse float: {0}.'.format(value)) + + +def _ConvertBool(value, require_str): + """Convert a boolean value. + + Args: + value: A scalar value to convert. + require_str: If True, value must be a str. + + Returns: + The bool parsed. + + Raises: + ParseError: If a boolean value couldn't be consumed. + """ + if require_str: + if value == 'true': + return True + elif value == 'false': + return False + else: + raise ParseError('Expected "true" or "false", not {0}.'.format(value)) + + if not isinstance(value, bool): + raise ParseError('Expected true or false without quotes.') + return value + +_WKTJSONMETHODS = { + 'google.protobuf.Any': ['_AnyMessageToJsonObject', + '_ConvertAnyMessage'], + 'google.protobuf.Duration': ['_GenericMessageToJsonObject', + '_ConvertGenericMessage'], + 'google.protobuf.FieldMask': ['_GenericMessageToJsonObject', + '_ConvertGenericMessage'], + 'google.protobuf.ListValue': ['_ListValueMessageToJsonObject', + '_ConvertListValueMessage'], + 'google.protobuf.Struct': ['_StructMessageToJsonObject', + '_ConvertStructMessage'], + 'google.protobuf.Timestamp': ['_GenericMessageToJsonObject', + '_ConvertGenericMessage'], + 'google.protobuf.Value': ['_ValueMessageToJsonObject', + '_ConvertValueMessage'] +} |