ProtocolBuffer.py

import base64
import binascii


class ProtocolBuffer:
    def __init__(self):
        self.buffer = []

    def __encode_int(self, number):
        while number:
            mod = number % 128
            number >>= 7
            if number:
                mod += 128

            self.buffer.append(mod)

    def reset(self):
        self.buffer = []

    def update(self, data, raw=False):

        if raw is True:
            self.buffer.append(data)

        else:
            data_type = type(data).__name__

            if data_type == "bool":
                self.buffer.append(1 if data is True else 0)

            elif data_type == "int":
                self.__encode_int(data)

            elif data_type == "str":
                self.__encode_int(len(data))
                for c in data:
                    self.buffer.append(ord(c))

            else:
                raise Exception("Unhandled data type : " + data_type)

        return self.buffer

    def finalize(self, b64=True):
        if not b64:
            stream = ""
            for data in self.buffer:
                stream += chr(data)
            return stream
        else:
            stream_hex = ""
            for data in self.buffer:
                stream_hex += ('%02x' % data)
            return base64.b64encode(binascii.a2b_hex(stream_hex))