Initial Contribution
diff --git a/froofle/protobuf/message.py b/froofle/protobuf/message.py
new file mode 100644
index 0000000..ed71485
--- /dev/null
+++ b/froofle/protobuf/message.py
@@ -0,0 +1,246 @@
+# Protocol Buffers - Google's data interchange format
+# Copyright 2008 Google Inc. All rights reserved.
+# http://code.google.com/p/protobuf/
+#
+# 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.
+
+# TODO(robinson): We should just make these methods all "pure-virtual" and move
+# all implementation out, into reflection.py for now.
+
+
+"""Contains an abstract base class for protocol messages."""
+
+__author__ = 'robinson@google.com (Will Robinson)'
+
+from froofle.protobuf import text_format
+
+class Error(Exception): pass
+class DecodeError(Error): pass
+class EncodeError(Error): pass
+
+
+class Message(object):
+
+ """Abstract base class for protocol messages.
+
+ Protocol message classes are almost always generated by the protocol
+ compiler. These generated types subclass Message and implement the methods
+ shown below.
+
+ TODO(robinson): Link to an HTML document here.
+
+ TODO(robinson): Document that instances of this class will also
+ have an Extensions attribute with __getitem__ and __setitem__.
+ Again, not sure how to best convey this.
+
+ TODO(robinson): Document that the class must also have a static
+ RegisterExtension(extension_field) method.
+ Not sure how to best express at this point.
+ """
+
+ # TODO(robinson): Document these fields and methods.
+
+ __slots__ = []
+
+ DESCRIPTOR = None
+
+ def __eq__(self, other_msg):
+ raise NotImplementedError
+
+ def __ne__(self, other_msg):
+ # Can't just say self != other_msg, since that would infinitely recurse. :)
+ return not self == other_msg
+
+ def __str__(self):
+ return text_format.MessageToString(self)
+
+ def MergeFrom(self, other_msg):
+ """Merges the contents of the specified message into current message.
+
+ This method merges the contents of the specified message into the current
+ message. Singular fields that are set in the specified message overwrite
+ the corresponding fields in the current message. Repeated fields are
+ appended. Singular sub-messages and groups are recursively merged.
+
+ Args:
+ other_msg: Message to merge into the current message.
+ """
+ raise NotImplementedError
+
+ def CopyFrom(self, other_msg):
+ """Copies the content of the specified message into the current message.
+
+ The method clears the current message and then merges the specified
+ message using MergeFrom.
+
+ Args:
+ other_msg: Message to copy into the current one.
+ """
+ if self == other_msg:
+ return
+ self.Clear()
+ self.MergeFrom(other_msg)
+
+ def Clear(self):
+ """Clears all data that was set in the message."""
+ raise NotImplementedError
+
+ def IsInitialized(self):
+ """Checks if the message is initialized.
+
+ Returns:
+ The method returns True if the message is initialized (i.e. all of its
+ required fields are set).
+ """
+ raise NotImplementedError
+
+ # TODO(robinson): MergeFromString() should probably return None and be
+ # implemented in terms of a helper that returns the # of bytes read. Our
+ # deserialization routines would use the helper when recursively
+ # deserializing, but the end user would almost always just want the no-return
+ # MergeFromString().
+
+ def MergeFromString(self, serialized):
+ """Merges serialized protocol buffer data into this message.
+
+ When we find a field in |serialized| that is already present
+ in this message:
+ - If it's a "repeated" field, we append to the end of our list.
+ - Else, if it's a scalar, we overwrite our field.
+ - Else, (it's a nonrepeated composite), we recursively merge
+ into the existing composite.
+
+ TODO(robinson): Document handling of unknown fields.
+
+ Args:
+ serialized: Any object that allows us to call buffer(serialized)
+ to access a string of bytes using the buffer interface.
+
+ TODO(robinson): When we switch to a helper, this will return None.
+
+ Returns:
+ The number of bytes read from |serialized|.
+ For non-group messages, this will always be len(serialized),
+ but for messages which are actually groups, this will
+ generally be less than len(serialized), since we must
+ stop when we reach an END_GROUP tag. Note that if
+ we *do* stop because of an END_GROUP tag, the number
+ of bytes returned does not include the bytes
+ for the END_GROUP tag information.
+ """
+ raise NotImplementedError
+
+ def ParseFromString(self, serialized):
+ """Like MergeFromString(), except we clear the object first."""
+ self.Clear()
+ self.MergeFromString(serialized)
+
+ def SerializeToString(self):
+ """Serializes the protocol message to a binary string.
+
+ Returns:
+ A binary string representation of the message if all of the required
+ fields in the message are set (i.e. the message is initialized).
+
+ Raises:
+ message.EncodeError if the message isn't initialized.
+ """
+ raise NotImplementedError
+
+ def SerializePartialToString(self):
+ """Serializes the protocol message to a binary string.
+
+ This method is similar to SerializeToString but doesn't check if the
+ message is initialized.
+
+ Returns:
+ A string representation of the partial message.
+ """
+ raise NotImplementedError
+
+ # TODO(robinson): Decide whether we like these better
+ # than auto-generated has_foo() and clear_foo() methods
+ # on the instances themselves. This way is less consistent
+ # with C++, but it makes reflection-type access easier and
+ # reduces the number of magically autogenerated things.
+ #
+ # TODO(robinson): Be sure to document (and test) exactly
+ # which field names are accepted here. Are we case-sensitive?
+ # What do we do with fields that share names with Python keywords
+ # like 'lambda' and 'yield'?
+ #
+ # nnorwitz says:
+ # """
+ # Typically (in python), an underscore is appended to names that are
+ # keywords. So they would become lambda_ or yield_.
+ # """
+ def ListFields(self, field_name):
+ """Returns a list of (FieldDescriptor, value) tuples for all
+ fields in the message which are not empty. A singular field is non-empty
+ if HasField() would return true, and a repeated field is non-empty if
+ it contains at least one element. The fields are ordered by field
+ number"""
+ raise NotImplementedError
+
+ def HasField(self, field_name):
+ raise NotImplementedError
+
+ def ClearField(self, field_name):
+ raise NotImplementedError
+
+ def HasExtension(self, extension_handle):
+ raise NotImplementedError
+
+ def ClearExtension(self, extension_handle):
+ raise NotImplementedError
+
+ def ByteSize(self):
+ """Returns the serialized size of this message.
+ Recursively calls ByteSize() on all contained messages.
+ """
+ raise NotImplementedError
+
+ def _SetListener(self, message_listener):
+ """Internal method used by the protocol message implementation.
+ Clients should not call this directly.
+
+ Sets a listener that this message will call on certain state transitions.
+
+ The purpose of this method is to register back-edges from children to
+ parents at runtime, for the purpose of setting "has" bits and
+ byte-size-dirty bits in the parent and ancestor objects whenever a child or
+ descendant object is modified.
+
+ If the client wants to disconnect this Message from the object tree, she
+ explicitly sets callback to None.
+
+ If message_listener is None, unregisters any existing listener. Otherwise,
+ message_listener must implement the MessageListener interface in
+ internal/message_listener.py, and we discard any listener registered
+ via a previous _SetListener() call.
+ """
+ raise NotImplementedError