def _deserializeMessageField(self, message, field, data):
"""
Mutates C{message} based on C{data} and C{field}.
C{message} is a L{google.protobuf.message.Message}.
C{field} is a L{google.protobuf.descriptor.FieldDescriptor}.
C{data} is a L{list}, L{int}, L{long}, L{float}, L{bool}, L{str},
L{unicode}, or L{NoneType}.
"""
isBool = (field.type == TYPE_BOOL)
isEnum = (field.type == TYPE_ENUM)
if field.label == LABEL_REPEATED:
messageField = getattr(message, field.name)
if field.type not in MESSAGE_OR_GROUP:
for value in _getIterator(data):
if isBool:
value = _convertToBool(value)
elif isEnum:
_ensureValidEnum(field, value)
try:
messageField.append(value)
except (TypeError, ValueError), e:
raise PbDecodeError(str(e))
else:
for subdata in _getIterator(data):
self._deserializeMessage(messageField.add(), subdata)
def _deserializeMessage(self, message, data):
"""
Mutates C{message} based on C{data}.
C{message} is a L{google.protobuf.message.Message}.
C{data} is a L{list}.
"""
for tag, field in message.DESCRIPTOR.fields_by_number.iteritems():
try:
subdata = data[tag]
except IndexError:
if tag > (len(data) -
1) and field.label == FieldDescriptor.LABEL_OPTIONAL:
# Deals with the fact that the js pblite serializer leaves off
# null optional fields at the end of a message. The len(data) must
# be adjusted because there's always a null value in the first position
# and because tags are 1-indexed by default.
#
# Since these fields are null, we don't bother deserializing them.
# Plus if we did, the value of subdata would be wrong.
continue
else:
raise PbDecodeError("For message %r expected index "
"%r but it was missing." %
(message, tag))
self._deserializeMessageField(message, field, subdata)
def _getIterator(obj):
"""
Returns C{obj.__iter__()} or raises a L{PbDecodeError}.
"""
try:
return obj.__iter__()
except (TypeError, AttributeError):
raise PbDecodeError("Expected an iterable object but "
"found a %r" % (type(obj), ))
def _ensureValidEnum(field, obj):
# Protocol Buffers' Python module (as of 2010-07-18) allows setting
# an enum field to an invalid value. This can lead to all sorts of
# terrible bugs. Here we dig into the field and check if the value is
# allowed. I filed a bug to get this fixed in protobuf:
# https://code.google.com/p/protobuf/issues/detail?id=206
if obj not in field.enum_type.values_by_number:
raise PbDecodeError("Expected a valid value for "
"%r, but didn't get one." % (field, ))
def _deserializeMessage(self, message, data):
"""
Mutates C{message} based on C{data}.
C{message} is a L{google.protobuf.message.Message}.
C{data} is a L{list}.
"""
for tag, field in message.DESCRIPTOR.fields_by_number.iteritems():
try:
subdata = data[tag]
except IndexError:
# Raise even if it was an optional field.
raise PbDecodeError("For message %r expected index "
"%r but it was missing." % (message, tag))
self._deserializeMessageField(message, field, subdata)
def _convertToBool(obj):
if obj not in (0, 1):
raise PbDecodeError("Expected a value == "
"to 0 or 1, but found a %r" % (type(obj), ))
return (obj == 1)
raise PbDecodeError(str(e))
else:
for subdata in _getIterator(data):
self._deserializeMessage(messageField.add(), subdata)
else:
if field.type not in MESSAGE_OR_GROUP:
if isBool:
data = _convertToBool(data)
elif isEnum:
_ensureValidEnum(field, data)
# Because setattr(..., ..., None) for optional fields is
# okay, we don't need our own branching here.
try:
setattr(message, field.name, data)
except (TypeError, ValueError), e:
raise PbDecodeError(str(e))
else:
# On "singular fields", we can just grab a child and set
# properties on it. Setting a field on the child will cause
# the child's field to exist in the parent. See:
# https://code.google.com/apis/protocolbuffers/docs/reference/python-generated.html#fields
messageField = getattr(message, field.name)
self._deserializeMessage(messageField, data)
def _deserializeMessage(self, message, data):
"""
Mutates C{message} based on C{data}.
C{message} is a L{google.protobuf.message.Message}.
C{data} is a L{list}.
"""