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1# Protocol Buffers - Google's data interchange format
2# Copyright 2008 Google Inc.  All rights reserved.
3# https://developers.google.com/protocol-buffers/
4#
5# Redistribution and use in source and binary forms, with or without
6# modification, are permitted provided that the following conditions are
7# met:
8#
9#     * Redistributions of source code must retain the above copyright
10# notice, this list of conditions and the following disclaimer.
11#     * Redistributions in binary form must reproduce the above
12# copyright notice, this list of conditions and the following disclaimer
13# in the documentation and/or other materials provided with the
14# distribution.
15#     * Neither the name of Google Inc. nor the names of its
16# contributors may be used to endorse or promote products derived from
17# this software without specific prior written permission.
18#
19# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
20# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
21# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
22# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
23# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
24# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
25# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
29# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30
31"""Contains routines for printing protocol messages in JSON format.
32
33Simple usage example:
34
35  # Create a proto object and serialize it to a json format string.
36  message = my_proto_pb2.MyMessage(foo='bar')
37  json_string = json_format.MessageToJson(message)
38
39  # Parse a json format string to proto object.
40  message = json_format.Parse(json_string, my_proto_pb2.MyMessage())
41"""
42
43__author__ = 'jieluo@google.com (Jie Luo)'
44
45# pylint: disable=g-statement-before-imports,g-import-not-at-top
46try:
47  from collections import OrderedDict
48except ImportError:
49  from ordereddict import OrderedDict  # PY26
50# pylint: enable=g-statement-before-imports,g-import-not-at-top
51
52import base64
53import json
54import math
55
56from operator import methodcaller
57
58import re
59import sys
60
61import six
62
63from google.protobuf.internal import type_checkers
64from google.protobuf import descriptor
65from google.protobuf import symbol_database
66
67
68_TIMESTAMPFOMAT = '%Y-%m-%dT%H:%M:%S'
69_INT_TYPES = frozenset([descriptor.FieldDescriptor.CPPTYPE_INT32,
70                        descriptor.FieldDescriptor.CPPTYPE_UINT32,
71                        descriptor.FieldDescriptor.CPPTYPE_INT64,
72                        descriptor.FieldDescriptor.CPPTYPE_UINT64])
73_INT64_TYPES = frozenset([descriptor.FieldDescriptor.CPPTYPE_INT64,
74                          descriptor.FieldDescriptor.CPPTYPE_UINT64])
75_FLOAT_TYPES = frozenset([descriptor.FieldDescriptor.CPPTYPE_FLOAT,
76                          descriptor.FieldDescriptor.CPPTYPE_DOUBLE])
77_INFINITY = 'Infinity'
78_NEG_INFINITY = '-Infinity'
79_NAN = 'NaN'
80
81_UNPAIRED_SURROGATE_PATTERN = re.compile(six.u(
82    r'[\ud800-\udbff](?![\udc00-\udfff])|(?<![\ud800-\udbff])[\udc00-\udfff]'
83))
84
85_VALID_EXTENSION_NAME = re.compile(r'\[[a-zA-Z0-9\._]*\]$')
86
87
88class Error(Exception):
89  """Top-level module error for json_format."""
90
91
92class SerializeToJsonError(Error):
93  """Thrown if serialization to JSON fails."""
94
95
96class ParseError(Error):
97  """Thrown in case of parsing error."""
98
99
100def MessageToJson(
101    message,
102    including_default_value_fields=False,
103    preserving_proto_field_name=False,
104    indent=2,
105    sort_keys=False,
106    use_integers_for_enums=False,
107    descriptor_pool=None,
108    float_precision=None):
109  """Converts protobuf message to JSON format.
110
111  Args:
112    message: The protocol buffers message instance to serialize.
113    including_default_value_fields: If True, singular primitive fields,
114        repeated fields, and map fields will always be serialized.  If
115        False, only serialize non-empty fields.  Singular message fields
116        and oneof fields are not affected by this option.
117    preserving_proto_field_name: If True, use the original proto field
118        names as defined in the .proto file. If False, convert the field
119        names to lowerCamelCase.
120    indent: The JSON object will be pretty-printed with this indent level.
121        An indent level of 0 or negative will only insert newlines.
122    sort_keys: If True, then the output will be sorted by field names.
123    use_integers_for_enums: If true, print integers instead of enum names.
124    descriptor_pool: A Descriptor Pool for resolving types. If None use the
125        default.
126    float_precision: If set, use this to specify float field valid digits.
127
128  Returns:
129    A string containing the JSON formatted protocol buffer message.
130  """
131  printer = _Printer(
132      including_default_value_fields,
133      preserving_proto_field_name,
134      use_integers_for_enums,
135      descriptor_pool,
136      float_precision=float_precision)
137  return printer.ToJsonString(message, indent, sort_keys)
138
139
140def MessageToDict(
141    message,
142    including_default_value_fields=False,
143    preserving_proto_field_name=False,
144    use_integers_for_enums=False,
145    descriptor_pool=None,
146    float_precision=None):
147  """Converts protobuf message to a dictionary.
148
149  When the dictionary is encoded to JSON, it conforms to proto3 JSON spec.
150
151  Args:
152    message: The protocol buffers message instance to serialize.
153    including_default_value_fields: If True, singular primitive fields,
154        repeated fields, and map fields will always be serialized.  If
155        False, only serialize non-empty fields.  Singular message fields
156        and oneof fields are not affected by this option.
157    preserving_proto_field_name: If True, use the original proto field
158        names as defined in the .proto file. If False, convert the field
159        names to lowerCamelCase.
160    use_integers_for_enums: If true, print integers instead of enum names.
161    descriptor_pool: A Descriptor Pool for resolving types. If None use the
162        default.
163    float_precision: If set, use this to specify float field valid digits.
164
165  Returns:
166    A dict representation of the protocol buffer message.
167  """
168  printer = _Printer(
169      including_default_value_fields,
170      preserving_proto_field_name,
171      use_integers_for_enums,
172      descriptor_pool,
173      float_precision=float_precision)
174  # pylint: disable=protected-access
175  return printer._MessageToJsonObject(message)
176
177
178def _IsMapEntry(field):
179  return (field.type == descriptor.FieldDescriptor.TYPE_MESSAGE and
180          field.message_type.has_options and
181          field.message_type.GetOptions().map_entry)
182
183
184class _Printer(object):
185  """JSON format printer for protocol message."""
186
187  def __init__(
188      self,
189      including_default_value_fields=False,
190      preserving_proto_field_name=False,
191      use_integers_for_enums=False,
192      descriptor_pool=None,
193      float_precision=None):
194    self.including_default_value_fields = including_default_value_fields
195    self.preserving_proto_field_name = preserving_proto_field_name
196    self.use_integers_for_enums = use_integers_for_enums
197    self.descriptor_pool = descriptor_pool
198    if float_precision:
199      self.float_format = '.{}g'.format(float_precision)
200    else:
201      self.float_format = None
202
203  def ToJsonString(self, message, indent, sort_keys):
204    js = self._MessageToJsonObject(message)
205    return json.dumps(js, indent=indent, sort_keys=sort_keys)
206
207  def _MessageToJsonObject(self, message):
208    """Converts message to an object according to Proto3 JSON Specification."""
209    message_descriptor = message.DESCRIPTOR
210    full_name = message_descriptor.full_name
211    if _IsWrapperMessage(message_descriptor):
212      return self._WrapperMessageToJsonObject(message)
213    if full_name in _WKTJSONMETHODS:
214      return methodcaller(_WKTJSONMETHODS[full_name][0], message)(self)
215    js = {}
216    return self._RegularMessageToJsonObject(message, js)
217
218  def _RegularMessageToJsonObject(self, message, js):
219    """Converts normal message according to Proto3 JSON Specification."""
220    fields = message.ListFields()
221
222    try:
223      for field, value in fields:
224        if self.preserving_proto_field_name:
225          name = field.name
226        else:
227          name = field.json_name
228        if _IsMapEntry(field):
229          # Convert a map field.
230          v_field = field.message_type.fields_by_name['value']
231          js_map = {}
232          for key in value:
233            if isinstance(key, bool):
234              if key:
235                recorded_key = 'true'
236              else:
237                recorded_key = 'false'
238            else:
239              recorded_key = key
240            js_map[recorded_key] = self._FieldToJsonObject(
241                v_field, value[key])
242          js[name] = js_map
243        elif field.label == descriptor.FieldDescriptor.LABEL_REPEATED:
244          # Convert a repeated field.
245          js[name] = [self._FieldToJsonObject(field, k)
246                      for k in value]
247        elif field.is_extension:
248          name = '[%s]' % field.full_name
249          js[name] = self._FieldToJsonObject(field, value)
250        else:
251          js[name] = self._FieldToJsonObject(field, value)
252
253      # Serialize default value if including_default_value_fields is True.
254      if self.including_default_value_fields:
255        message_descriptor = message.DESCRIPTOR
256        for field in message_descriptor.fields:
257          # Singular message fields and oneof fields will not be affected.
258          if ((field.label != descriptor.FieldDescriptor.LABEL_REPEATED and
259               field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_MESSAGE) or
260              field.containing_oneof):
261            continue
262          if self.preserving_proto_field_name:
263            name = field.name
264          else:
265            name = field.json_name
266          if name in js:
267            # Skip the field which has been serialized already.
268            continue
269          if _IsMapEntry(field):
270            js[name] = {}
271          elif field.label == descriptor.FieldDescriptor.LABEL_REPEATED:
272            js[name] = []
273          else:
274            js[name] = self._FieldToJsonObject(field, field.default_value)
275
276    except ValueError as e:
277      raise SerializeToJsonError(
278          'Failed to serialize {0} field: {1}.'.format(field.name, e))
279
280    return js
281
282  def _FieldToJsonObject(self, field, value):
283    """Converts field value according to Proto3 JSON Specification."""
284    if field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_MESSAGE:
285      return self._MessageToJsonObject(value)
286    elif field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_ENUM:
287      if self.use_integers_for_enums:
288        return value
289      enum_value = field.enum_type.values_by_number.get(value, None)
290      if enum_value is not None:
291        return enum_value.name
292      else:
293        if field.file.syntax == 'proto3':
294          return value
295        raise SerializeToJsonError('Enum field contains an integer value '
296                                   'which can not mapped to an enum value.')
297    elif field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_STRING:
298      if field.type == descriptor.FieldDescriptor.TYPE_BYTES:
299        # Use base64 Data encoding for bytes
300        return base64.b64encode(value).decode('utf-8')
301      else:
302        return value
303    elif field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_BOOL:
304      return bool(value)
305    elif field.cpp_type in _INT64_TYPES:
306      return str(value)
307    elif field.cpp_type in _FLOAT_TYPES:
308      if math.isinf(value):
309        if value < 0.0:
310          return _NEG_INFINITY
311        else:
312          return _INFINITY
313      if math.isnan(value):
314        return _NAN
315      if field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_FLOAT:
316        if self.float_format:
317          return float(format(value, self.float_format))
318        else:
319          return type_checkers.ToShortestFloat(value)
320
321    return value
322
323  def _AnyMessageToJsonObject(self, message):
324    """Converts Any message according to Proto3 JSON Specification."""
325    if not message.ListFields():
326      return {}
327    # Must print @type first, use OrderedDict instead of {}
328    js = OrderedDict()
329    type_url = message.type_url
330    js['@type'] = type_url
331    sub_message = _CreateMessageFromTypeUrl(type_url, self.descriptor_pool)
332    sub_message.ParseFromString(message.value)
333    message_descriptor = sub_message.DESCRIPTOR
334    full_name = message_descriptor.full_name
335    if _IsWrapperMessage(message_descriptor):
336      js['value'] = self._WrapperMessageToJsonObject(sub_message)
337      return js
338    if full_name in _WKTJSONMETHODS:
339      js['value'] = methodcaller(_WKTJSONMETHODS[full_name][0],
340                                 sub_message)(self)
341      return js
342    return self._RegularMessageToJsonObject(sub_message, js)
343
344  def _GenericMessageToJsonObject(self, message):
345    """Converts message according to Proto3 JSON Specification."""
346    # Duration, Timestamp and FieldMask have ToJsonString method to do the
347    # convert. Users can also call the method directly.
348    return message.ToJsonString()
349
350  def _ValueMessageToJsonObject(self, message):
351    """Converts Value message according to Proto3 JSON Specification."""
352    which = message.WhichOneof('kind')
353    # If the Value message is not set treat as null_value when serialize
354    # to JSON. The parse back result will be different from original message.
355    if which is None or which == 'null_value':
356      return None
357    if which == 'list_value':
358      return self._ListValueMessageToJsonObject(message.list_value)
359    if which == 'struct_value':
360      value = message.struct_value
361    else:
362      value = getattr(message, which)
363    oneof_descriptor = message.DESCRIPTOR.fields_by_name[which]
364    return self._FieldToJsonObject(oneof_descriptor, value)
365
366  def _ListValueMessageToJsonObject(self, message):
367    """Converts ListValue message according to Proto3 JSON Specification."""
368    return [self._ValueMessageToJsonObject(value)
369            for value in message.values]
370
371  def _StructMessageToJsonObject(self, message):
372    """Converts Struct message according to Proto3 JSON Specification."""
373    fields = message.fields
374    ret = {}
375    for key in fields:
376      ret[key] = self._ValueMessageToJsonObject(fields[key])
377    return ret
378
379  def _WrapperMessageToJsonObject(self, message):
380    return self._FieldToJsonObject(
381        message.DESCRIPTOR.fields_by_name['value'], message.value)
382
383
384def _IsWrapperMessage(message_descriptor):
385  return message_descriptor.file.name == 'google/protobuf/wrappers.proto'
386
387
388def _DuplicateChecker(js):
389  result = {}
390  for name, value in js:
391    if name in result:
392      raise ParseError('Failed to load JSON: duplicate key {0}.'.format(name))
393    result[name] = value
394  return result
395
396
397def _CreateMessageFromTypeUrl(type_url, descriptor_pool):
398  """Creates a message from a type URL."""
399  db = symbol_database.Default()
400  pool = db.pool if descriptor_pool is None else descriptor_pool
401  type_name = type_url.split('/')[-1]
402  try:
403    message_descriptor = pool.FindMessageTypeByName(type_name)
404  except KeyError:
405    raise TypeError(
406        'Can not find message descriptor by type_url: {0}.'.format(type_url))
407  message_class = db.GetPrototype(message_descriptor)
408  return message_class()
409
410
411def Parse(text, message, ignore_unknown_fields=False, descriptor_pool=None):
412  """Parses a JSON representation of a protocol message into a message.
413
414  Args:
415    text: Message JSON representation.
416    message: A protocol buffer message to merge into.
417    ignore_unknown_fields: If True, do not raise errors for unknown fields.
418    descriptor_pool: A Descriptor Pool for resolving types. If None use the
419        default.
420
421  Returns:
422    The same message passed as argument.
423
424  Raises::
425    ParseError: On JSON parsing problems.
426  """
427  if not isinstance(text, six.text_type): text = text.decode('utf-8')
428  try:
429    js = json.loads(text, object_pairs_hook=_DuplicateChecker)
430  except ValueError as e:
431    raise ParseError('Failed to load JSON: {0}.'.format(str(e)))
432  return ParseDict(js, message, ignore_unknown_fields, descriptor_pool)
433
434
435def ParseDict(js_dict,
436              message,
437              ignore_unknown_fields=False,
438              descriptor_pool=None):
439  """Parses a JSON dictionary representation into a message.
440
441  Args:
442    js_dict: Dict representation of a JSON message.
443    message: A protocol buffer message to merge into.
444    ignore_unknown_fields: If True, do not raise errors for unknown fields.
445    descriptor_pool: A Descriptor Pool for resolving types. If None use the
446      default.
447
448  Returns:
449    The same message passed as argument.
450  """
451  parser = _Parser(ignore_unknown_fields, descriptor_pool)
452  parser.ConvertMessage(js_dict, message)
453  return message
454
455
456_INT_OR_FLOAT = six.integer_types + (float,)
457
458
459class _Parser(object):
460  """JSON format parser for protocol message."""
461
462  def __init__(self, ignore_unknown_fields, descriptor_pool):
463    self.ignore_unknown_fields = ignore_unknown_fields
464    self.descriptor_pool = descriptor_pool
465
466  def ConvertMessage(self, value, message):
467    """Convert a JSON object into a message.
468
469    Args:
470      value: A JSON object.
471      message: A WKT or regular protocol message to record the data.
472
473    Raises:
474      ParseError: In case of convert problems.
475    """
476    message_descriptor = message.DESCRIPTOR
477    full_name = message_descriptor.full_name
478    if _IsWrapperMessage(message_descriptor):
479      self._ConvertWrapperMessage(value, message)
480    elif full_name in _WKTJSONMETHODS:
481      methodcaller(_WKTJSONMETHODS[full_name][1], value, message)(self)
482    else:
483      self._ConvertFieldValuePair(value, message)
484
485  def _ConvertFieldValuePair(self, js, message):
486    """Convert field value pairs into regular message.
487
488    Args:
489      js: A JSON object to convert the field value pairs.
490      message: A regular protocol message to record the data.
491
492    Raises:
493      ParseError: In case of problems converting.
494    """
495    names = []
496    message_descriptor = message.DESCRIPTOR
497    fields_by_json_name = dict((f.json_name, f)
498                               for f in message_descriptor.fields)
499    for name in js:
500      try:
501        field = fields_by_json_name.get(name, None)
502        if not field:
503          field = message_descriptor.fields_by_name.get(name, None)
504        if not field and _VALID_EXTENSION_NAME.match(name):
505          if not message_descriptor.is_extendable:
506            raise ParseError('Message type {0} does not have extensions'.format(
507                message_descriptor.full_name))
508          identifier = name[1:-1]  # strip [] brackets
509          # pylint: disable=protected-access
510          field = message.Extensions._FindExtensionByName(identifier)
511          # pylint: enable=protected-access
512          if not field:
513            # Try looking for extension by the message type name, dropping the
514            # field name following the final . separator in full_name.
515            identifier = '.'.join(identifier.split('.')[:-1])
516            # pylint: disable=protected-access
517            field = message.Extensions._FindExtensionByName(identifier)
518            # pylint: enable=protected-access
519        if not field:
520          if self.ignore_unknown_fields:
521            continue
522          raise ParseError(
523              ('Message type "{0}" has no field named "{1}".\n'
524               ' Available Fields(except extensions): {2}').format(
525                   message_descriptor.full_name, name,
526                   [f.json_name for f in message_descriptor.fields]))
527        if name in names:
528          raise ParseError('Message type "{0}" should not have multiple '
529                           '"{1}" fields.'.format(
530                               message.DESCRIPTOR.full_name, name))
531        names.append(name)
532        # Check no other oneof field is parsed.
533        if field.containing_oneof is not None:
534          oneof_name = field.containing_oneof.name
535          if oneof_name in names:
536            raise ParseError('Message type "{0}" should not have multiple '
537                             '"{1}" oneof fields.'.format(
538                                 message.DESCRIPTOR.full_name, oneof_name))
539          names.append(oneof_name)
540
541        value = js[name]
542        if value is None:
543          if (field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_MESSAGE
544              and field.message_type.full_name == 'google.protobuf.Value'):
545            sub_message = getattr(message, field.name)
546            sub_message.null_value = 0
547          else:
548            message.ClearField(field.name)
549          continue
550
551        # Parse field value.
552        if _IsMapEntry(field):
553          message.ClearField(field.name)
554          self._ConvertMapFieldValue(value, message, field)
555        elif field.label == descriptor.FieldDescriptor.LABEL_REPEATED:
556          message.ClearField(field.name)
557          if not isinstance(value, list):
558            raise ParseError('repeated field {0} must be in [] which is '
559                             '{1}.'.format(name, value))
560          if field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_MESSAGE:
561            # Repeated message field.
562            for item in value:
563              sub_message = getattr(message, field.name).add()
564              # None is a null_value in Value.
565              if (item is None and
566                  sub_message.DESCRIPTOR.full_name != 'google.protobuf.Value'):
567                raise ParseError('null is not allowed to be used as an element'
568                                 ' in a repeated field.')
569              self.ConvertMessage(item, sub_message)
570          else:
571            # Repeated scalar field.
572            for item in value:
573              if item is None:
574                raise ParseError('null is not allowed to be used as an element'
575                                 ' in a repeated field.')
576              getattr(message, field.name).append(
577                  _ConvertScalarFieldValue(item, field))
578        elif field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_MESSAGE:
579          if field.is_extension:
580            sub_message = message.Extensions[field]
581          else:
582            sub_message = getattr(message, field.name)
583          sub_message.SetInParent()
584          self.ConvertMessage(value, sub_message)
585        else:
586          if field.is_extension:
587            message.Extensions[field] = _ConvertScalarFieldValue(value, field)
588          else:
589            setattr(message, field.name, _ConvertScalarFieldValue(value, field))
590      except ParseError as e:
591        if field and field.containing_oneof is None:
592          raise ParseError('Failed to parse {0} field: {1}.'.format(name, e))
593        else:
594          raise ParseError(str(e))
595      except ValueError as e:
596        raise ParseError('Failed to parse {0} field: {1}.'.format(name, e))
597      except TypeError as e:
598        raise ParseError('Failed to parse {0} field: {1}.'.format(name, e))
599
600  def _ConvertAnyMessage(self, value, message):
601    """Convert a JSON representation into Any message."""
602    if isinstance(value, dict) and not value:
603      return
604    try:
605      type_url = value['@type']
606    except KeyError:
607      raise ParseError('@type is missing when parsing any message.')
608
609    sub_message = _CreateMessageFromTypeUrl(type_url, self.descriptor_pool)
610    message_descriptor = sub_message.DESCRIPTOR
611    full_name = message_descriptor.full_name
612    if _IsWrapperMessage(message_descriptor):
613      self._ConvertWrapperMessage(value['value'], sub_message)
614    elif full_name in _WKTJSONMETHODS:
615      methodcaller(
616          _WKTJSONMETHODS[full_name][1], value['value'], sub_message)(self)
617    else:
618      del value['@type']
619      self._ConvertFieldValuePair(value, sub_message)
620      value['@type'] = type_url
621    # Sets Any message
622    message.value = sub_message.SerializeToString()
623    message.type_url = type_url
624
625  def _ConvertGenericMessage(self, value, message):
626    """Convert a JSON representation into message with FromJsonString."""
627    # Duration, Timestamp, FieldMask have a FromJsonString method to do the
628    # conversion. Users can also call the method directly.
629    try:
630      message.FromJsonString(value)
631    except ValueError as e:
632      raise ParseError(e)
633
634  def _ConvertValueMessage(self, value, message):
635    """Convert a JSON representation into Value message."""
636    if isinstance(value, dict):
637      self._ConvertStructMessage(value, message.struct_value)
638    elif isinstance(value, list):
639      self. _ConvertListValueMessage(value, message.list_value)
640    elif value is None:
641      message.null_value = 0
642    elif isinstance(value, bool):
643      message.bool_value = value
644    elif isinstance(value, six.string_types):
645      message.string_value = value
646    elif isinstance(value, _INT_OR_FLOAT):
647      message.number_value = value
648    else:
649      raise ParseError('Value {0} has unexpected type {1}.'.format(
650          value, type(value)))
651
652  def _ConvertListValueMessage(self, value, message):
653    """Convert a JSON representation into ListValue message."""
654    if not isinstance(value, list):
655      raise ParseError(
656          'ListValue must be in [] which is {0}.'.format(value))
657    message.ClearField('values')
658    for item in value:
659      self._ConvertValueMessage(item, message.values.add())
660
661  def _ConvertStructMessage(self, value, message):
662    """Convert a JSON representation into Struct message."""
663    if not isinstance(value, dict):
664      raise ParseError(
665          'Struct must be in a dict which is {0}.'.format(value))
666    # Clear will mark the struct as modified so it will be created even if
667    # there are no values.
668    message.Clear()
669    for key in value:
670      self._ConvertValueMessage(value[key], message.fields[key])
671    return
672
673  def _ConvertWrapperMessage(self, value, message):
674    """Convert a JSON representation into Wrapper message."""
675    field = message.DESCRIPTOR.fields_by_name['value']
676    setattr(message, 'value', _ConvertScalarFieldValue(value, field))
677
678  def _ConvertMapFieldValue(self, value, message, field):
679    """Convert map field value for a message map field.
680
681    Args:
682      value: A JSON object to convert the map field value.
683      message: A protocol message to record the converted data.
684      field: The descriptor of the map field to be converted.
685
686    Raises:
687      ParseError: In case of convert problems.
688    """
689    if not isinstance(value, dict):
690      raise ParseError(
691          'Map field {0} must be in a dict which is {1}.'.format(
692              field.name, value))
693    key_field = field.message_type.fields_by_name['key']
694    value_field = field.message_type.fields_by_name['value']
695    for key in value:
696      key_value = _ConvertScalarFieldValue(key, key_field, True)
697      if value_field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_MESSAGE:
698        self.ConvertMessage(value[key], getattr(
699            message, field.name)[key_value])
700      else:
701        getattr(message, field.name)[key_value] = _ConvertScalarFieldValue(
702            value[key], value_field)
703
704
705def _ConvertScalarFieldValue(value, field, require_str=False):
706  """Convert a single scalar field value.
707
708  Args:
709    value: A scalar value to convert the scalar field value.
710    field: The descriptor of the field to convert.
711    require_str: If True, the field value must be a str.
712
713  Returns:
714    The converted scalar field value
715
716  Raises:
717    ParseError: In case of convert problems.
718  """
719  if field.cpp_type in _INT_TYPES:
720    return _ConvertInteger(value)
721  elif field.cpp_type in _FLOAT_TYPES:
722    return _ConvertFloat(value, field)
723  elif field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_BOOL:
724    return _ConvertBool(value, require_str)
725  elif field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_STRING:
726    if field.type == descriptor.FieldDescriptor.TYPE_BYTES:
727      if isinstance(value, six.text_type):
728        encoded = value.encode('utf-8')
729      else:
730        encoded = value
731      # Add extra padding '='
732      padded_value = encoded + b'=' * (4 - len(encoded) % 4)
733      return base64.urlsafe_b64decode(padded_value)
734    else:
735      # Checking for unpaired surrogates appears to be unreliable,
736      # depending on the specific Python version, so we check manually.
737      if _UNPAIRED_SURROGATE_PATTERN.search(value):
738        raise ParseError('Unpaired surrogate')
739      return value
740  elif field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_ENUM:
741    # Convert an enum value.
742    enum_value = field.enum_type.values_by_name.get(value, None)
743    if enum_value is None:
744      try:
745        number = int(value)
746        enum_value = field.enum_type.values_by_number.get(number, None)
747      except ValueError:
748        raise ParseError('Invalid enum value {0} for enum type {1}.'.format(
749            value, field.enum_type.full_name))
750      if enum_value is None:
751        if field.file.syntax == 'proto3':
752          # Proto3 accepts unknown enums.
753          return number
754        raise ParseError('Invalid enum value {0} for enum type {1}.'.format(
755            value, field.enum_type.full_name))
756    return enum_value.number
757
758
759def _ConvertInteger(value):
760  """Convert an integer.
761
762  Args:
763    value: A scalar value to convert.
764
765  Returns:
766    The integer value.
767
768  Raises:
769    ParseError: If an integer couldn't be consumed.
770  """
771  if isinstance(value, float) and not value.is_integer():
772    raise ParseError('Couldn\'t parse integer: {0}.'.format(value))
773
774  if isinstance(value, six.text_type) and value.find(' ') != -1:
775    raise ParseError('Couldn\'t parse integer: "{0}".'.format(value))
776
777  if isinstance(value, bool):
778    raise ParseError('Bool value {0} is not acceptable for '
779                     'integer field.'.format(value))
780
781  return int(value)
782
783
784def _ConvertFloat(value, field):
785  """Convert an floating point number."""
786  if isinstance(value, float):
787    if math.isnan(value):
788      raise ParseError('Couldn\'t parse NaN, use quoted "NaN" instead.')
789    if math.isinf(value):
790      if value > 0:
791        raise ParseError('Couldn\'t parse Infinity or value too large, '
792                         'use quoted "Infinity" instead.')
793      else:
794        raise ParseError('Couldn\'t parse -Infinity or value too small, '
795                         'use quoted "-Infinity" instead.')
796    if field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_FLOAT:
797      # pylint: disable=protected-access
798      if value > type_checkers._FLOAT_MAX:
799        raise ParseError('Float value too large')
800      # pylint: disable=protected-access
801      if value < type_checkers._FLOAT_MIN:
802        raise ParseError('Float value too small')
803  if value == 'nan':
804    raise ParseError('Couldn\'t parse float "nan", use "NaN" instead.')
805  try:
806    # Assume Python compatible syntax.
807    return float(value)
808  except ValueError:
809    # Check alternative spellings.
810    if value == _NEG_INFINITY:
811      return float('-inf')
812    elif value == _INFINITY:
813      return float('inf')
814    elif value == _NAN:
815      return float('nan')
816    else:
817      raise ParseError('Couldn\'t parse float: {0}.'.format(value))
818
819
820def _ConvertBool(value, require_str):
821  """Convert a boolean value.
822
823  Args:
824    value: A scalar value to convert.
825    require_str: If True, value must be a str.
826
827  Returns:
828    The bool parsed.
829
830  Raises:
831    ParseError: If a boolean value couldn't be consumed.
832  """
833  if require_str:
834    if value == 'true':
835      return True
836    elif value == 'false':
837      return False
838    else:
839      raise ParseError('Expected "true" or "false", not {0}.'.format(value))
840
841  if not isinstance(value, bool):
842    raise ParseError('Expected true or false without quotes.')
843  return value
844
845_WKTJSONMETHODS = {
846    'google.protobuf.Any': ['_AnyMessageToJsonObject',
847                            '_ConvertAnyMessage'],
848    'google.protobuf.Duration': ['_GenericMessageToJsonObject',
849                                 '_ConvertGenericMessage'],
850    'google.protobuf.FieldMask': ['_GenericMessageToJsonObject',
851                                  '_ConvertGenericMessage'],
852    'google.protobuf.ListValue': ['_ListValueMessageToJsonObject',
853                                  '_ConvertListValueMessage'],
854    'google.protobuf.Struct': ['_StructMessageToJsonObject',
855                               '_ConvertStructMessage'],
856    'google.protobuf.Timestamp': ['_GenericMessageToJsonObject',
857                                  '_ConvertGenericMessage'],
858    'google.protobuf.Value': ['_ValueMessageToJsonObject',
859                              '_ConvertValueMessage']
860}
861