blob: 5290f821aa3ab3c43a055cd028eb64b4f08fbba5 [file] [log] [blame]
#!/usr/bin/env python
#
# Copyright 2007 Google Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
"""Contains routines for printing protocol messages in text format."""
import cStringIO
import re
from google.net.proto2.python.internal import type_checkers
from google.net.proto2.python.public import descriptor
from google.net.proto2.python.public import text_encoding
__all__ = ['MessageToString', 'PrintMessage', 'PrintField',
'PrintFieldValue', 'Merge']
_INTEGER_CHECKERS = (type_checkers.Uint32ValueChecker(),
type_checkers.Int32ValueChecker(),
type_checkers.Uint64ValueChecker(),
type_checkers.Int64ValueChecker())
_FLOAT_INFINITY = re.compile('-?inf(?:inity)?f?', re.IGNORECASE)
_FLOAT_NAN = re.compile('nanf?', re.IGNORECASE)
_FLOAT_TYPES = frozenset([descriptor.FieldDescriptor.CPPTYPE_FLOAT,
descriptor.FieldDescriptor.CPPTYPE_DOUBLE])
class Error(Exception):
"""Top-level module error for text_format."""
class ParseError(Error):
"""Thrown in case of ASCII parsing error."""
def MessageToString(message, as_utf8=False, as_one_line=False,
pointy_brackets=False, use_index_order=False,
float_format=None):
"""Convert protobuf message to text format.
Floating point values can be formatted compactly with 15 digits of
precision (which is the most that IEEE 754 "double" can guarantee)
using float_format='.15g'.
Args:
message: The protocol buffers message.
as_utf8: Produce text output in UTF8 format.
as_one_line: Don't introduce newlines between fields.
pointy_brackets: If True, use angle brackets instead of curly braces for
nesting.
use_index_order: If True, print fields of a proto message using the order
defined in source code instead of the field number. By default, use the
field number order.
float_format: If set, use this to specify floating point number formatting
(per the "Format Specification Mini-Language"); otherwise, str() is used.
Returns:
A string of the text formatted protocol buffer message.
"""
out = cStringIO.StringIO()
PrintMessage(message, out, as_utf8=as_utf8, as_one_line=as_one_line,
pointy_brackets=pointy_brackets,
use_index_order=use_index_order,
float_format=float_format)
result = out.getvalue()
out.close()
if as_one_line:
return result.rstrip()
return result
def PrintMessage(message, out, indent=0, as_utf8=False, as_one_line=False,
pointy_brackets=False, use_index_order=False,
float_format=None):
fields = message.ListFields()
if use_index_order:
fields.sort(key=lambda x: x[0].index)
for field, value in fields:
if field.label == descriptor.FieldDescriptor.LABEL_REPEATED:
for element in value:
PrintField(field, element, out, indent, as_utf8, as_one_line,
pointy_brackets=pointy_brackets,
use_index_order=use_index_order,
float_format=float_format)
else:
PrintField(field, value, out, indent, as_utf8, as_one_line,
pointy_brackets=pointy_brackets,
use_index_order=use_index_order,
float_format=float_format)
def PrintField(field, value, out, indent=0, as_utf8=False, as_one_line=False,
pointy_brackets=False, use_index_order=False, float_format=None):
"""Print a single field name/value pair. For repeated fields, the value
should be a single element."""
out.write(' ' * indent)
if field.is_extension:
out.write('[')
if (field.containing_type.GetOptions().message_set_wire_format and
field.type == descriptor.FieldDescriptor.TYPE_MESSAGE and
field.message_type == field.extension_scope and
field.label == descriptor.FieldDescriptor.LABEL_OPTIONAL):
out.write(field.message_type.full_name)
else:
out.write(field.full_name)
out.write(']')
elif field.type == descriptor.FieldDescriptor.TYPE_GROUP:
out.write(field.message_type.name)
else:
out.write(field.name)
if field.cpp_type != descriptor.FieldDescriptor.CPPTYPE_MESSAGE:
out.write(': ')
PrintFieldValue(field, value, out, indent, as_utf8, as_one_line,
pointy_brackets=pointy_brackets,
use_index_order=use_index_order,
float_format=float_format)
if as_one_line:
out.write(' ')
else:
out.write('\n')
def PrintFieldValue(field, value, out, indent=0, as_utf8=False,
as_one_line=False, pointy_brackets=False,
use_index_order=False,
float_format=None):
"""Print a single field value (not including name). For repeated fields,
the value should be a single element."""
if pointy_brackets:
openb = '<'
closeb = '>'
else:
openb = '{'
closeb = '}'
if field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_MESSAGE:
if as_one_line:
out.write(' %s ' % openb)
PrintMessage(value, out, indent, as_utf8, as_one_line,
pointy_brackets=pointy_brackets,
use_index_order=use_index_order,
float_format=float_format)
out.write(closeb)
else:
out.write(' %s\n' % openb)
PrintMessage(value, out, indent + 2, as_utf8, as_one_line,
pointy_brackets=pointy_brackets,
use_index_order=use_index_order,
float_format=float_format)
out.write(' ' * indent + closeb)
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:
out.write(enum_value.name)
else:
out.write(str(value))
elif field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_STRING:
out.write('\"')
if isinstance(value, unicode):
out_value = value.encode('utf-8')
else:
out_value = value
if field.type == descriptor.FieldDescriptor.TYPE_BYTES:
out_as_utf8 = False
else:
out_as_utf8 = as_utf8
out.write(text_encoding.CEscape(out_value, out_as_utf8))
out.write('\"')
elif field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_BOOL:
if value:
out.write('true')
else:
out.write('false')
elif field.cpp_type in _FLOAT_TYPES and float_format is not None:
out.write('{1:{0}}'.format(float_format, value))
else:
out.write(str(value))
def _ParseOrMerge(lines, message, allow_multiple_scalars):
"""Converts an ASCII representation of a protocol message into a message.
Args:
lines: Lines of a message's ASCII representation.
message: A protocol buffer message to merge into.
allow_multiple_scalars: Determines if repeated values for a non-repeated
field are permitted, e.g., the string "foo: 1 foo: 2" for a
required/optional field named "foo".
Raises:
ParseError: On ASCII parsing problems.
"""
tokenizer = _Tokenizer(lines)
while not tokenizer.AtEnd():
_MergeField(tokenizer, message, allow_multiple_scalars)
def Parse(text, message):
"""Parses an ASCII representation of a protocol message into a message.
Args:
text: Message ASCII representation.
message: A protocol buffer message to merge into.
Returns:
The same message passed as argument.
Raises:
ParseError: On ASCII parsing problems.
"""
if not isinstance(text, str): text = text.decode('utf-8')
return ParseLines(text.split('\n'), message)
def Merge(text, message):
"""Parses an ASCII representation of a protocol message into a message.
Like Parse(), but allows repeated values for a non-repeated field, and uses
the last one.
Args:
text: Message ASCII representation.
message: A protocol buffer message to merge into.
Returns:
The same message passed as argument.
Raises:
ParseError: On ASCII parsing problems.
"""
return MergeLines(text.split('\n'), message)
def ParseLines(lines, message):
"""Parses an ASCII representation of a protocol message into a message.
Args:
lines: An iterable of lines of a message's ASCII representation.
message: A protocol buffer message to merge into.
Returns:
The same message passed as argument.
Raises:
ParseError: On ASCII parsing problems.
"""
_ParseOrMerge(lines, message, False)
return message
def MergeLines(lines, message):
"""Parses an ASCII representation of a protocol message into a message.
Args:
lines: An iterable of lines of a message's ASCII representation.
message: A protocol buffer message to merge into.
Returns:
The same message passed as argument.
Raises:
ParseError: On ASCII parsing problems.
"""
_ParseOrMerge(lines, message, True)
return message
def _MergeField(tokenizer, message, allow_multiple_scalars):
"""Merges a single protocol message field into a message.
Args:
tokenizer: A tokenizer to parse the field name and values.
message: A protocol message to record the data.
allow_multiple_scalars: Determines if repeated values for a non-repeated
field are permitted, e.g., the string "foo: 1 foo: 2" for a
required/optional field named "foo".
Raises:
ParseError: In case of ASCII parsing problems.
"""
message_descriptor = message.DESCRIPTOR
if tokenizer.TryConsume('['):
name = [tokenizer.ConsumeIdentifier()]
while tokenizer.TryConsume('.'):
name.append(tokenizer.ConsumeIdentifier())
name = '.'.join(name)
if not message_descriptor.is_extendable:
raise tokenizer.ParseErrorPreviousToken(
'Message type "%s" does not have extensions.' %
message_descriptor.full_name)
field = message.Extensions._FindExtensionByName(name)
if not field:
raise tokenizer.ParseErrorPreviousToken(
'Extension "%s" not registered.' % name)
elif message_descriptor != field.containing_type:
raise tokenizer.ParseErrorPreviousToken(
'Extension "%s" does not extend message type "%s".' % (
name, message_descriptor.full_name))
tokenizer.Consume(']')
else:
name = tokenizer.ConsumeIdentifier()
field = message_descriptor.fields_by_name.get(name, None)
if not field:
field = message_descriptor.fields_by_name.get(name.lower(), None)
if field and field.type != descriptor.FieldDescriptor.TYPE_GROUP:
field = None
if (field and field.type == descriptor.FieldDescriptor.TYPE_GROUP and
field.message_type.name != name):
field = None
if not field:
raise tokenizer.ParseErrorPreviousToken(
'Message type "%s" has no field named "%s".' % (
message_descriptor.full_name, name))
if field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_MESSAGE:
tokenizer.TryConsume(':')
if tokenizer.TryConsume('<'):
end_token = '>'
else:
tokenizer.Consume('{')
end_token = '}'
if field.label == descriptor.FieldDescriptor.LABEL_REPEATED:
if field.is_extension:
sub_message = message.Extensions[field].add()
else:
sub_message = getattr(message, field.name).add()
else:
if field.is_extension:
sub_message = message.Extensions[field]
else:
sub_message = getattr(message, field.name)
sub_message.SetInParent()
while not tokenizer.TryConsume(end_token):
if tokenizer.AtEnd():
raise tokenizer.ParseErrorPreviousToken('Expected "%s".' % (end_token))
_MergeField(tokenizer, sub_message, allow_multiple_scalars)
else:
_MergeScalarField(tokenizer, message, field, allow_multiple_scalars)
if not tokenizer.TryConsume(','):
tokenizer.TryConsume(';')
def _MergeScalarField(tokenizer, message, field, allow_multiple_scalars):
"""Merges a single protocol message scalar field into a message.
Args:
tokenizer: A tokenizer to parse the field value.
message: A protocol message to record the data.
field: The descriptor of the field to be merged.
allow_multiple_scalars: Determines if repeated values for a non-repeated
field are permitted, e.g., the string "foo: 1 foo: 2" for a
required/optional field named "foo".
Raises:
ParseError: In case of ASCII parsing problems.
RuntimeError: On runtime errors.
"""
tokenizer.Consume(':')
value = None
if field.type in (descriptor.FieldDescriptor.TYPE_INT32,
descriptor.FieldDescriptor.TYPE_SINT32,
descriptor.FieldDescriptor.TYPE_SFIXED32):
value = tokenizer.ConsumeInt32()
elif field.type in (descriptor.FieldDescriptor.TYPE_INT64,
descriptor.FieldDescriptor.TYPE_SINT64,
descriptor.FieldDescriptor.TYPE_SFIXED64):
value = tokenizer.ConsumeInt64()
elif field.type in (descriptor.FieldDescriptor.TYPE_UINT32,
descriptor.FieldDescriptor.TYPE_FIXED32):
value = tokenizer.ConsumeUint32()
elif field.type in (descriptor.FieldDescriptor.TYPE_UINT64,
descriptor.FieldDescriptor.TYPE_FIXED64):
value = tokenizer.ConsumeUint64()
elif field.type in (descriptor.FieldDescriptor.TYPE_FLOAT,
descriptor.FieldDescriptor.TYPE_DOUBLE):
value = tokenizer.ConsumeFloat()
elif field.type == descriptor.FieldDescriptor.TYPE_BOOL:
value = tokenizer.ConsumeBool()
elif field.type == descriptor.FieldDescriptor.TYPE_STRING:
value = tokenizer.ConsumeString()
elif field.type == descriptor.FieldDescriptor.TYPE_BYTES:
value = tokenizer.ConsumeByteString()
elif field.type == descriptor.FieldDescriptor.TYPE_ENUM:
value = tokenizer.ConsumeEnum(field)
else:
raise RuntimeError('Unknown field type %d' % field.type)
if field.label == descriptor.FieldDescriptor.LABEL_REPEATED:
if field.is_extension:
message.Extensions[field].append(value)
else:
getattr(message, field.name).append(value)
else:
if field.is_extension:
if not allow_multiple_scalars and message.HasExtension(field):
raise tokenizer.ParseErrorPreviousToken(
'Message type "%s" should not have multiple "%s" extensions.' %
(message.DESCRIPTOR.full_name, field.full_name))
else:
message.Extensions[field] = value
else:
if not allow_multiple_scalars and message.HasField(field.name):
raise tokenizer.ParseErrorPreviousToken(
'Message type "%s" should not have multiple "%s" fields.' %
(message.DESCRIPTOR.full_name, field.name))
else:
setattr(message, field.name, value)
class _Tokenizer(object):
"""Protocol buffer ASCII representation tokenizer.
This class handles the lower level string parsing by splitting it into
meaningful tokens.
It was directly ported from the Java protocol buffer API.
"""
_WHITESPACE = re.compile('(\\s|(#.*$))+', re.MULTILINE)
_TOKEN = re.compile(
'[a-zA-Z_][0-9a-zA-Z_+-]*|'
'[0-9+-][0-9a-zA-Z_.+-]*|'
'\"([^\"\n\\\\]|\\\\.)*(\"|\\\\?$)|'
'\'([^\'\n\\\\]|\\\\.)*(\'|\\\\?$)')
_IDENTIFIER = re.compile(r'\w+')
def __init__(self, lines):
self._position = 0
self._line = -1
self._column = 0
self._token_start = None
self.token = ''
self._lines = iter(lines)
self._current_line = ''
self._previous_line = 0
self._previous_column = 0
self._more_lines = True
self._SkipWhitespace()
self.NextToken()
def AtEnd(self):
"""Checks the end of the text was reached.
Returns:
True iff the end was reached.
"""
return not self.token
def _PopLine(self):
while len(self._current_line) <= self._column:
try:
self._current_line = self._lines.next()
except StopIteration:
self._current_line = ''
self._more_lines = False
return
else:
self._line += 1
self._column = 0
def _SkipWhitespace(self):
while True:
self._PopLine()
match = self._WHITESPACE.match(self._current_line, self._column)
if not match:
break
length = len(match.group(0))
self._column += length
def TryConsume(self, token):
"""Tries to consume a given piece of text.
Args:
token: Text to consume.
Returns:
True iff the text was consumed.
"""
if self.token == token:
self.NextToken()
return True
return False
def Consume(self, token):
"""Consumes a piece of text.
Args:
token: Text to consume.
Raises:
ParseError: If the text couldn't be consumed.
"""
if not self.TryConsume(token):
raise self._ParseError('Expected "%s".' % token)
def ConsumeIdentifier(self):
"""Consumes protocol message field identifier.
Returns:
Identifier string.
Raises:
ParseError: If an identifier couldn't be consumed.
"""
result = self.token
if not self._IDENTIFIER.match(result):
raise self._ParseError('Expected identifier.')
self.NextToken()
return result
def ConsumeInt32(self):
"""Consumes a signed 32bit integer number.
Returns:
The integer parsed.
Raises:
ParseError: If a signed 32bit integer couldn't be consumed.
"""
try:
result = ParseInteger(self.token, is_signed=True, is_long=False)
except ValueError, e:
raise self._ParseError(str(e))
self.NextToken()
return result
def ConsumeUint32(self):
"""Consumes an unsigned 32bit integer number.
Returns:
The integer parsed.
Raises:
ParseError: If an unsigned 32bit integer couldn't be consumed.
"""
try:
result = ParseInteger(self.token, is_signed=False, is_long=False)
except ValueError, e:
raise self._ParseError(str(e))
self.NextToken()
return result
def ConsumeInt64(self):
"""Consumes a signed 64bit integer number.
Returns:
The integer parsed.
Raises:
ParseError: If a signed 64bit integer couldn't be consumed.
"""
try:
result = ParseInteger(self.token, is_signed=True, is_long=True)
except ValueError, e:
raise self._ParseError(str(e))
self.NextToken()
return result
def ConsumeUint64(self):
"""Consumes an unsigned 64bit integer number.
Returns:
The integer parsed.
Raises:
ParseError: If an unsigned 64bit integer couldn't be consumed.
"""
try:
result = ParseInteger(self.token, is_signed=False, is_long=True)
except ValueError, e:
raise self._ParseError(str(e))
self.NextToken()
return result
def ConsumeFloat(self):
"""Consumes an floating point number.
Returns:
The number parsed.
Raises:
ParseError: If a floating point number couldn't be consumed.
"""
try:
result = ParseFloat(self.token)
except ValueError, e:
raise self._ParseError(str(e))
self.NextToken()
return result
def ConsumeBool(self):
"""Consumes a boolean value.
Returns:
The bool parsed.
Raises:
ParseError: If a boolean value couldn't be consumed.
"""
try:
result = ParseBool(self.token)
except ValueError, e:
raise self._ParseError(str(e))
self.NextToken()
return result
def ConsumeString(self):
"""Consumes a string value.
Returns:
The string parsed.
Raises:
ParseError: If a string value couldn't be consumed.
"""
the_bytes = self.ConsumeByteString()
try:
return unicode(the_bytes, 'utf-8')
except UnicodeDecodeError, e:
raise self._StringParseError(e)
def ConsumeByteString(self):
"""Consumes a byte array value.
Returns:
The array parsed (as a string).
Raises:
ParseError: If a byte array value couldn't be consumed.
"""
the_list = [self._ConsumeSingleByteString()]
while self.token and self.token[0] in ('\'', '"'):
the_list.append(self._ConsumeSingleByteString())
return ''.encode('latin1').join(the_list)
def _ConsumeSingleByteString(self):
"""Consume one token of a string literal.
String literals (whether bytes or text) can come in multiple adjacent
tokens which are automatically concatenated, like in C or Python. This
method only consumes one token.
"""
text = self.token
if len(text) < 1 or text[0] not in ('\'', '"'):
raise self._ParseError('Expected string.')
if len(text) < 2 or text[-1] != text[0]:
raise self._ParseError('String missing ending quote.')
try:
result = text_encoding.CUnescape(text[1:-1])
except ValueError, e:
raise self._ParseError(str(e))
self.NextToken()
return result
def ConsumeEnum(self, field):
try:
result = ParseEnum(field, self.token)
except ValueError, e:
raise self._ParseError(str(e))
self.NextToken()
return result
def ParseErrorPreviousToken(self, message):
"""Creates and *returns* a ParseError for the previously read token.
Args:
message: A message to set for the exception.
Returns:
A ParseError instance.
"""
return ParseError('%d:%d : %s' % (
self._previous_line + 1, self._previous_column + 1, message))
def _ParseError(self, message):
"""Creates and *returns* a ParseError for the current token."""
return ParseError('%d:%d : %s' % (
self._line + 1, self._column + 1, message))
def _StringParseError(self, e):
return self._ParseError('Couldn\'t parse string: ' + str(e))
def NextToken(self):
"""Reads the next meaningful token."""
self._previous_line = self._line
self._previous_column = self._column
self._column += len(self.token)
self._SkipWhitespace()
if not self._more_lines:
self.token = ''
return
match = self._TOKEN.match(self._current_line, self._column)
if match:
token = match.group(0)
self.token = token
else:
self.token = self._current_line[self._column]
def ParseInteger(text, is_signed=False, is_long=False):
"""Parses an integer.
Args:
text: The text to parse.
is_signed: True if a signed integer must be parsed.
is_long: True if a long integer must be parsed.
Returns:
The integer value.
Raises:
ValueError: Thrown Iff the text is not a valid integer.
"""
try:
if is_long:
result = long(text, 0)
else:
result = int(text, 0)
except ValueError:
raise ValueError('Couldn\'t parse integer: %s' % text)
checker = _INTEGER_CHECKERS[2 * int(is_long) + int(is_signed)]
checker.CheckValue(result)
return result
def ParseFloat(text):
"""Parse a floating point number.
Args:
text: Text to parse.
Returns:
The number parsed.
Raises:
ValueError: If a floating point number couldn't be parsed.
"""
try:
return float(text)
except ValueError:
if _FLOAT_INFINITY.match(text):
if text[0] == '-':
return float('-inf')
else:
return float('inf')
elif _FLOAT_NAN.match(text):
return float('nan')
else:
try:
return float(text.rstrip('f'))
except ValueError:
raise ValueError('Couldn\'t parse float: %s' % text)
def ParseBool(text):
"""Parse a boolean value.
Args:
text: Text to parse.
Returns:
Boolean values parsed
Raises:
ValueError: If text is not a valid boolean.
"""
if text in ('true', 't', '1'):
return True
elif text in ('false', 'f', '0'):
return False
else:
raise ValueError('Expected "true" or "false".')
def ParseEnum(field, value):
"""Parse an enum value.
The value can be specified by a number (the enum value), or by
a string literal (the enum name).
Args:
field: Enum field descriptor.
value: String value.
Returns:
Enum value number.
Raises:
ValueError: If the enum value could not be parsed.
"""
enum_descriptor = field.enum_type
try:
number = int(value, 0)
except ValueError:
enum_value = enum_descriptor.values_by_name.get(value, None)
if enum_value is None:
raise ValueError(
'Enum type "%s" has no value named %s.' % (
enum_descriptor.full_name, value))
else:
enum_value = enum_descriptor.values_by_number.get(number, None)
if enum_value is None:
raise ValueError(
'Enum type "%s" has no value with number %d.' % (
enum_descriptor.full_name, number))
return enum_value.number