Exemple #1
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    def write(self, previous=None):
        """
        Write (encoder) header to byte string.

        @param previous: previous header (used to compress header)
        @type previous: L{RTMPHeader}
        @return: encoded header
        @rtype: C{str}
        """
        if previous is None:
            diff = 3
        else:
            diff = self.diff(previous)

        first = self.object_id & 0x3f | ((diff ^ 3) << 6)

        if diff == 0:
            return chr(first)

        buf = BufferedByteStream()
        buf.write_uchar(first)

        buf.write_24bit_uint(self.timestamp)

        if diff > 1:
            buf.write_24bit_uint(self.length)
            buf.write_uchar(self.type)

            if diff > 2:
                buf.write_ulong(self.stream_id)

        buf.seek(0, 0)
        return buf.read()
Exemple #2
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    def write(self, previous=None):
        """
        Write (encoder) header to byte string.

        @param previous: previous header (used to compress header)
        @type previous: L{RTMPHeader}
        @return: encoded header
        @rtype: C{str}
        """
        if previous is None:
            diff = 3
        else:
            diff = self.diff(previous)

        first = self.object_id & 0x3F | ((diff ^ 3) << 6)

        if diff == 0:
            return chr(first)

        buf = BufferedByteStream()
        buf.write_uchar(first)

        buf.write_24bit_uint(self.timestamp)

        if diff > 1:
            buf.write_24bit_uint(self.length)
            buf.write_uchar(self.type)

            if diff > 2:
                buf.write_ulong(self.stream_id)

        buf.seek(0, 0)
        return buf.read()
Exemple #3
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    def write(self):
        """
        Encode packet into bytes.

        @return: representation of packet
        @rtype: C{str}
        """
        buf = BufferedByteStream()
        buf.write_ulong(self.bytes)
        self.header.length = len(buf)
        buf.seek(0, 0)
        return buf.read()
Exemple #4
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    def write(self):
        """
        Encode packet into bytes.

        @return: representation of packet
        @rtype: C{str}
        """
        buf = BufferedByteStream()
        buf.write_ulong(self.bytes)
        self.header.length = len(buf)
        buf.seek(0, 0)
        return buf.read()
Exemple #5
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class ProducingChannel(BaseChannel):
    """
    Writes RTMP frames.

    @ivar buffer: Any data waiting to be written to the underlying stream.
    @type buffer: L{BufferedByteStream}
    @ivar acquired: Whether this channel is acquired. See L{ChannelMuxer.
        acquireChannel}
    """


    def __init__(self, channelId, stream, frameSize):
        BaseChannel.__init__(self, channelId, stream, frameSize)

        self.buffer = BufferedByteStream()
        self.acquired = False
        self.callback = None


    def setCallback(self, cb):
        """
        Sets the callback that will be fired once this channel has been completely
        encoded.
        """
        self.callback = cb


    def reset(self):
        """
        Called when the channel has completed writing the buffer.
        """
        BaseChannel.reset(self)

        self.buffer.seek(0)
        self.buffer.truncate()
        self.header = None


    def append(self, data):
        """
        Appends data to the buffer in preparation of encoding in RTMP.
        """
        self.buffer.append(data)


    def marshallFrame(self, size):
        """
        Writes a section of the buffer as part of the RTMP frame.
        """
        self.stream.write(self.buffer.read(size))
Exemple #6
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class ProducingChannel(BaseChannel):
    """
    Writes RTMP frames.

    @ivar buffer: Any data waiting to be written to the underlying stream.
    @type buffer: L{BufferedByteStream}
    @ivar acquired: Whether this channel is acquired. See L{ChannelMuxer.
        acquireChannel}
    """


    def __init__(self, channelId, stream, frameSize):
        BaseChannel.__init__(self, channelId, stream, frameSize)

        self.buffer = BufferedByteStream()
        self.acquired = False
        self.callback = None


    def setCallback(self, cb):
        """
        Sets the callback that will be fired once this channel has been completely
        encoded.
        """
        self.callback = cb


    def reset(self):
        """
        Called when the channel has completed writing the buffer.
        """
        BaseChannel.reset(self)

        self.buffer.seek(0)
        self.buffer.truncate()
        self.header = None


    def append(self, data):
        """
        Appends data to the buffer in preparation of encoding in RTMP.
        """
        self.buffer.append(data)


    def marshallFrame(self, size):
        """
        Writes a section of the buffer as part of the RTMP frame.
        """
        self.stream.write(self.buffer.read(size))
Exemple #7
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class BaseNegotiator(object):
    """
    Base functionality for negotiating an RTMP handshake.

    Call L{start} to begin negotiations.

    @ivar observer: An observer for handshake negotiations.
    @type observer: L{IHandshakeObserver}
    @ivar started: Whether negotiations have begun.
    @type started: C{bool}
    @ivar _buffer: Any data that has been received but not yet been consumed.
    @type _buffer: L{BufferedByteStream}
    """


    started = False

    nearRequest = None
    nearResponse = None

    farRequest = None
    farResponse = None

    protocolVersion = 3
    farProtocolVersion = None


    def __init__(self, observer, output):
        self.observer = observer
        self.output = output


    def start(self, uptime=0, version=0):
        """
        Called to start the handshaking negotiations.
        """
        if self.started:
            raise AlreadyStarted('Handshake negotiator cannot be restarted')

        self.started = True

        self.uptime = uptime
        self.version = version

        self._buffer = BufferedByteStream()


    def readPacket(self):
        if self._buffer.remaining() < HANDSHAKE_LENGTH:
            # we're expecting more data
            return

        packet = self._buffer.read(HANDSHAKE_LENGTH)
        self._buffer.consume()

        return packet


    def dataReceived(self, data):
        """
        Called when handshake data has been received.
        """
        if not self.started:
            raise HandshakeError('Data received, but negotiator not started')

        self._buffer.append(data)

        if self.farProtocolVersion is None:
            self.farProtocolVersion = self._buffer.read_uchar()

        packet = self.readPacket()

        if not packet:
            return

        if not self.farRequest:
            self.farRequest = self.buildFarRequest()

            self.farRequest.decode(packet)

            self.farRequestReceived(self.farRequest)

            packet = self.readPacket()

            if not packet:
                return

        if not self.farResponse:
            self.farResponse = self.buildFarResponse()

            self.farResponse.decode(packet)

            self.farResponseReceived(self.farResponse)


    def buildFarRequest(self):
        """
        """
        return RequestPacket()


    def buildFarResponse(self):
        """
        """
        return ResponsePacket()


    def buildNearRequest(self):
        """
        """
        p = RequestPacket()

        p.uptime = self.uptime
        p.version = self.version

        return p


    def buildNearResponse(self):
        """
        """
        return ResponsePacket()


    def farRequestReceived(self, request):
        """
        Called when request packet has been received from the peer.
        """
        raise NotImplementedError


    def farResponseReceived(self, response):
        """
        Called when response packet has been received from the peer.
        """
        raise NotImplementedError
Exemple #8
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class Packet(object):
    """
    """


    format = None
    challengeKey = None


    def __init__(self):
        self.buffer = BufferedByteStream()


    def computeOffset(self, start, modulus, increment):
        """
        An offset is 4 consecutive bytes encoded at C{start}.

        s = sum of bytes

        offset = (s % modulus) + increment
        """
        self.buffer.seek(start)

        offset = (
            self.buffer.read_uchar() +
            self.buffer.read_uchar() +
            self.buffer.read_uchar() +
            self.buffer.read_uchar())

        offset %= modulus
        offset += increment

        return offset


    def getDigestAndPayload(self, offset, length):
        """
        Returns the C{digest} and C{payload} components.
        """
        self.buffer.seek(0)

        payload = self.buffer.read(offset)
        digest = self.buffer.read(length)
        payload += self.buffer.read()

        return digest, payload


    def setFormat(self, format):
        self.format = format


    def setChallengeKey(self, key):
        self.challengeKey = key


    def setChallengeDigest(self, digest):
        self.challengeDigest = digest


    def decode(self, data):
        """
        Decodes the data bytes into this packet.
        """
        raise NotImplementedError
Exemple #9
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    def test_assemble_chunks(self):
        chunkSizes = (32, 64, 128, 256)
        header = RTMPHeader(object_id=2, timestamp=9504486, length=10, type=0x04, stream_id=0)

        for chunkSize in chunkSizes:
            for l in xrange(1, 258):
                data = ''.join([chr(random.randint(0, 255)) for x in xrange(l)])

                buf = BufferedByteStream()
                a = RTMPAssembler(chunkSize, buf)
                a.push_packet(DataPacket(header=header, data=data))

                buf.seek(0, 0)
                self.failUnlessEqual(''.join(self.gen_packet("\x02\x91\x06\xe6\x00\x00\x01\x04\x00\x00\x00\x00", ["\xc2"], data, l, chunkSize)), buf.read())
Exemple #10
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    def test_assemble(self):
        for fixture in self.data:
            buf = BufferedByteStream()
            a = RTMPAssembler(128, buf)

            for packet in fixture['packets']:
                a.push_packet(packet)

            buf.seek(0, 0)

            self.failUnlessEqual(struct.pack("B" * len(fixture['data']), *fixture['data']), buf.read())
Exemple #11
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class RTMPBaseProtocol(protocol.Protocol):
    """
    Basis RTMP protocol implementation.

    @ivar state: internal state of protocol
    @ivar input: input packet disassebmbler 
    @type input: L{RTMPDisassembler}
    @ivar output: output packet assembler
    @type output: L{RTMPAssembler}
    @ivar handshakeBuf: buffer, holding input data during handshake
    @type handshakeBuf: C{BufferedByteStream}
    """
    class State:
        CONNECTING = 'connecting'
        """
        Connection in progress
        """
        HANDSHAKE_SEND = 'handshake-send'
        """
        Handshake, 1st phase.
        """
        HANDSHAKE_VERIFY = 'handshake-verify'
        """
        Handshake, 2nd phase.
        """
        RUNNING = 'running'
        """
        Usual state of protocol: receiving-sending RTMP packets.
        """

    def __init__(self):
        """
        Constructor.
        """
        self.state = self.State.CONNECTING
        self.handshakeTimeout = None

    def connectionMade(self):
        """
        Successfully connected to peer.
        """
        self.input = RTMPDisassembler(constants.DEFAULT_CHUNK_SIZE)
        self.output = RTMPAssembler(constants.DEFAULT_CHUNK_SIZE,
                                    self.transport)

        self.state = self.State.HANDSHAKE_SEND
        self.handshakeTimeout = reactor.callLater(
            config.getint('RTMP', 'handshakeTimeout'), self._handshakeTimedout)
        self.handshakeBuf = BufferedByteStream()
        self._beginHandshake()

    def _beginHandshake(self):
        """
        Begin handshake procedures.

        Implemented in descendants.
        """
        raise NotImplementedError

    def _handshakeSendReceived(self):
        """
        Data received in HANDSHAKE_SEND state.

        Implemented in descendants.
        """
        raise NotImplementedError

    def _handshakeVerifyReceived(self):
        """
        Data received in HANDSHAKE_VERIFY state.

        Implemented in descendants.
        """
        raise NotImplementedError

    def _handshakeComplete(self):
        """
        Handshake complete, clear timeouts.
        """
        if self.handshakeTimeout is not None:
            self.handshakeTimeout.cancel()
            self.handshakeTimeout = None
        self.state = self.State.RUNNING
        self._regularInput(self.handshakeBuf.read())
        del self.handshakeBuf

    def _handshakeTimedout(self):
        """
        Handshake not completed in timeout.
        """
        self.handshakeTimeout = None
        self.transport.loseConnection()

    def connectionLost(self, reason):
        """
        Connection with peer was lost for some reason.
        """
        if self.handshakeTimeout is not None:
            self.handshakeTimeout.cancel()
            self.handshakeTimeout = None

    def _regularInput(self, data):
        """
        Regular RTMP dataflow: stream of RTMP packets.

        Some bytes (L{data}) was received.

        @param data: bytes received
        @type data: C{str}
        """
        self.input.push_data(data)

        while True:
            packet = self.input.disassemble()
            if packet is None:
                return

            self._handlePacket(packet)

    def dataReceived(self, data):
        """
        Some data was received from peer.

        @param data: bytes received
        @type data: C{str}
        """
        if self.state == self.State.RUNNING:
            self._regularInput(data)
        else:  # handshake
            self.handshakeBuf.seek(0, 2)
            self.handshakeBuf.write(data)
            if self.state == self.State.HANDSHAKE_SEND:
                self._handshakeSendReceived()
            elif self.state == self.State.HANDSHAKE_VERIFY:
                self._handshakeVerifyReceived()

    def _handlePacket(self, packet):
        """
        Dispatch received packet to some handler.

        @param packet: packet
        @type packet: L{Packet}
        """
        log.msg("<- %r" % packet)
        handler = 'handle' + packet.__class__.__name__
        try:
            getattr(self, handler)(packet)
        except AttributeError:
            log.msg("Unhandled packet: %r" % packet)

    def pushPacket(self, packet):
        """
        Push outgoing RTMP packet.

        @param packet: outgoing packet
        @type packet: L{Packet}.
        """
        log.msg("-> %r" % packet)
        self.output.push_packet(packet)
Exemple #12
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class RTMPBaseProtocol(protocol.Protocol):
    """
    Basis RTMP protocol implementation.

    @ivar state: internal state of protocol
    @ivar input: input packet disassebmbler 
    @type input: L{RTMPDisassembler}
    @ivar output: output packet assembler
    @type output: L{RTMPAssembler}
    @ivar handshakeBuf: buffer, holding input data during handshake
    @type handshakeBuf: C{BufferedByteStream}
    """

    class State:
        CONNECTING = 'connecting'
        """
        Connection in progress
        """
        HANDSHAKE_SEND = 'handshake-send'
        """
        Handshake, 1st phase.
        """
        HANDSHAKE_VERIFY = 'handshake-verify'
        """
        Handshake, 2nd phase.
        """
        RUNNING = 'running'
        """
        Usual state of protocol: receiving-sending RTMP packets.
        """

    def __init__(self):
        """
        Constructor.
        """
        self.state = self.State.CONNECTING
        self.handshakeTimeout = None

    def connectionMade(self):
        """
        Successfully connected to peer.
        """
        self.input = RTMPDisassembler(constants.DEFAULT_CHUNK_SIZE)
        self.output = RTMPAssembler(constants.DEFAULT_CHUNK_SIZE, self.transport)

        self.state = self.State.HANDSHAKE_SEND
        self.handshakeTimeout = reactor.callLater(config.getint('RTMP', 'handshakeTimeout'), self._handshakeTimedout)
        self.handshakeBuf = BufferedByteStream()
        self._beginHandshake()

    def _beginHandshake(self):
        """
        Begin handshake procedures.

        Implemented in descendants.
        """
        raise NotImplementedError

    def _handshakeSendReceived(self):
        """
        Data received in HANDSHAKE_SEND state.

        Implemented in descendants.
        """
        raise NotImplementedError

    def _handshakeVerifyReceived(self):
        """
        Data received in HANDSHAKE_VERIFY state.

        Implemented in descendants.
        """
        raise NotImplementedError

    def _handshakeComplete(self):
        """
        Handshake complete, clear timeouts.
        """
        if self.handshakeTimeout is not None:
            self.handshakeTimeout.cancel()
            self.handshakeTimeout = None
        self.state = self.State.RUNNING
        self._regularInput(self.handshakeBuf.read())
        del self.handshakeBuf

    def _handshakeTimedout(self):
        """
        Handshake not completed in timeout.
        """
        self.handshakeTimeout = None
        self.transport.loseConnection()

    def connectionLost(self, reason):
        """
        Connection with peer was lost for some reason.
        """
        if self.handshakeTimeout is not None:
            self.handshakeTimeout.cancel()
            self.handshakeTimeout = None

    def _regularInput(self, data):
        """
        Regular RTMP dataflow: stream of RTMP packets.

        Some bytes (L{data}) was received.

        @param data: bytes received
        @type data: C{str}
        """
        self.input.push_data(data)

        while True:
            packet = self.input.disassemble()
            if packet is None:
                return

            self._handlePacket(packet)

    def dataReceived(self, data):
        """
        Some data was received from peer.

        @param data: bytes received
        @type data: C{str}
        """
        if self.state == self.State.RUNNING:
            self._regularInput(data)
        else: # handshake
            self.handshakeBuf.seek(0, 2)
            self.handshakeBuf.write(data)
            if self.state == self.State.HANDSHAKE_SEND:
                self._handshakeSendReceived()
            elif self.state == self.State.HANDSHAKE_VERIFY:
                self._handshakeVerifyReceived()

    def _handlePacket(self, packet):
        """
        Dispatch received packet to some handler.

        @param packet: packet
        @type packet: L{Packet}
        """
        log.msg("<- %r" % packet)
        handler = 'handle' + packet.__class__.__name__
        try:
            getattr(self, handler)(packet)
        except AttributeError:
            log.msg("Unhandled packet: %r" % packet)

    def pushPacket(self, packet):
        """
        Push outgoing RTMP packet.

        @param packet: outgoing packet
        @type packet: L{Packet}.
        """
        log.msg("-> %r" % packet)
        self.output.push_packet(packet)
Exemple #13
0
class StateEngine(BaseStreamer):
    """
    There are three stages to the protocol negotiations before RTMP message
    streaming can begin.

    Stage 1 - Version negotiation::

    The first byte in any RTMP connection is the I{protocol version} byte. This
    allows endpoints to negotiate which version of the protocol to proceed with.

    Valid values appear to be::

    - C{0x03}: plain old RTMP this is the baseline protocol that all
        implementations should default to.
    - C{0x06}: Used to signify an RTMPE connection.

    There is another (C{0x08}) but not documented at this time because how/why
    it is used is unclear.

    L{versionSuccess} must be called to move on to stage 2.

    Stage 2 - Handshake negotiations::

    The next 1536 * 2 bytes is handshaking data. This part is delegated to a
    handshake negotiator, which is based on the protocol version.

    L{handshakeSuccess} must be called to move on to stage 3.

    Stage 3 - RTMP Message streaming::


    Some docstring here.

    @ivar state: The state of the protocol.
    """

    STATE_VERSION = 'version'
    STATE_HANDSHAKE = 'handshake'
    STATE_STREAM = 'stream'

    state = None
    protocolVersion = 3


    def connectionMade(self):
        """
        Called when this a connection has been made.
        """
        self.state = self.STATE_VERSION

        self.startVersioning()


    def connectionLost(self, reason):
        """
        Called when the connection has been lost.

        @param reason: The reason for the disconnection
        """
        if self.state == self.STATE_VERSION:
            self.stopVersioning(reason)
        elif self.state == self.STATE_HANDSHAKE:
            self.stopHandshaking(reason)
        elif self.state == self.STATE_STREAM:
            self.stopStreaming(reason)


    def dataReceived(self, data):
        """
        """
        if self.state == self.STATE_VERSION:
            self.version_dataReceived(data)
        elif self.state == self.STATE_HANDSHAKE:
            self.handshake_dataReceived(data)
        elif self.state == self.STATE_STREAM:
            BaseStreamer.dataReceived(self, data)
        else:
            raise RuntimeError('Invalid state!')


    def startVersioning(self):
        """
        Start protocol version negotiations.
        """
        self.buffer = BufferedByteStream()


    def stopVersioning(self, reason=None):
        """
        Stop protocol version negotiations.

        @param reason: A L{failure.Failure} object if protocol version
            negotiations failed. C{None} means success.
        """
        del self.buffer


    def version_dataReceived(self, data):
        """
        """
        if not data:
            return

        self.buffer.append(data)

        self.peerProtocolVersion = self.buffer.read_uchar()

        self.versionReceived(self.peerProtocolVersion)


    def versionReceived(self, version):
        """
        Called when the peers' protocol version has been received.

        The default behaviour is to accept any known version. It is the
        responsibility for any overriding subclass to call L{versionSuccess} for
        negotiations to proceed.
        """
        if version == self.protocolVersion:
            self.versionSuccess()

            return

        raise UnknownProtocolVersion(
            'Unhandled protocol version %d' % (version,))


    def versionSuccess(self):
        """
        Protocol version negotiations have been successful, now on to
        handshaking.
        """
        try:
            data = self.buffer.read()
        except IOError:
            data = None

        self.stopVersioning()

        self.state = self.STATE_HANDSHAKE

        self.startHandshaking()

        if data:
            # any data that was left over from version negotiations is
            # artificially re-inserted back into the protocol because the
            # `state` has changed.
            self.dataReceived(data)


    def buildHandshakeNegotiator(self):
        """
        """
        raise NotImplementedError


    def startHandshaking(self):
        """
        """
        self.handshaker = self.buildHandshakeNegotiator()

        # TODO: apply uptime, version to the handshaker instead of 0, 0
        self.handshaker.start(0, 0)


    def stopHandshaking(self, reason=None):
        """
        """
        del self.handshaker


    def handshake_dataReceived(self, data):
        """
        """
        self.handshaker.dataReceived(data)


    def handshakeSuccess(self, data):
        """
        Handshaking was successful, streaming now commences.
        """
        #data = self.handshaker.getRemainingData()

        self.stopHandshaking()

        self.state = self.STATE_STREAM

        self.startStreaming()

        if data:
            self.dataReceived(data)


    def startStreaming(self):
        """
        Because Python is awesome we can short circuit checking state each time
        L{dataReceived} is called.
        """
        self.dataReceived = lambda x: BaseStreamer.dataReceived(self, x)

        return BaseStreamer.startStreaming(self)
Exemple #14
0
class RTMPDisassembler(object):
    """
    Disassembling bytestream into RTMP packets.

    RTMP stream slices packets into chunks of L{chunkSize}. This class
    processes incoming stream of RTMP protocol data (after initial handshake)
    and decodes RTMP packets.

    Communication goes independently for each object_id. Last received
    headers are stored for each object_id in L{lastHeaders}. L{pool} holds
    incomplete packet contents also for each object_id.

    @ivar lastHeaders: last received header for object_id
    @type lastHeaders: C{dict}, object_id -> L{RTMPHeader}
    @ivar pool: incomplete packet data for object_id
    @type pool: C{dict}, object_id -> L{BufferedByteStream}
    @ivar chunkSize: size of chunk for this stream
    @type chunkSize: C{int}
    @ivar buffer: incoming buffer with data received from protocol
    @type buffer: L{BufferedByteStream}
    """

    def __init__(self, chunkSize):
        """
        Constructor.

        @param chunkSize: initial size of chunk
        @type chunkSize: C{int}
        """
        self.lastHeaders = {}
        self.pool = {}
        self.chunkSize = chunkSize
        self.buffer = BufferedByteStream()

    def push_data(self, data):
        """
        Push more incoming data.

        @param data: data received
        @type data: C{str}
        """
        self.buffer.seek(0, 2)
        self.buffer.write(data)

        return self

    def disassemble(self):
        """
        Disassemble L{buffer} into packets.

        Returns first decoded packet or None, if no packet could
        be decoded at the moment.

        @return: decoded packet
        @rtype: L{Packet}
        """
        self.buffer.seek(0)

        while self.buffer.remaining() > 0:
            try:
                # try to parse header from stream
                header = RTMPHeader.read(self.buffer)
            except NeedBytes, (bytes,):
                # not enough bytes, return what we've already parsed
                return None

            # fill header with extra data from previous headers received
            # with same object_id
            header.fill(self.lastHeaders.get(header.object_id, RTMPHeader()))

            # get buffer for data of this packet
            buf = self.pool.get(header.object_id, BufferedByteStream())

            # this chunk size is minimum of regular chunk size in this
            # disassembler and what we have left here
            thisChunk = min(header.length - len(buf), self.chunkSize)
            if self.buffer.remaining() < thisChunk:
                # we have not enough bytes to read this chunk of data
                return None

            # we got complete chunk
            buf.write(self.buffer.read(thisChunk))

            # store packet header for this object_id
            self.lastHeaders[header.object_id] = header

            # skip data left in input buffer
            self.buffer.consume()

            # this chunk completes full packet?
            if len(buf) < header.length:
                # no, store buffer for further chunks
                self.pool[header.object_id] = buf
            else:
                # parse packet from header and data
                buf.seek(0, 0)

                # delete stored data for this packet
                if header.object_id in self.pool:
                    del self.pool[header.object_id]

                return self._decode_packet(header, buf)

        return None
Exemple #15
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class StateEngine(BaseStreamer):
    """
    There are three stages to the protocol negotiations before RTMP message
    streaming can begin.

    Stage 1 - Version negotiation::

    The first byte in any RTMP connection is the I{protocol version} byte. This
    allows endpoints to negotiate which version of the protocol to proceed with.

    Valid values appear to be::

    - C{0x03}: plain old RTMP this is the baseline protocol that all
        implementations should default to.
    - C{0x06}: Used to signify an RTMPE connection.

    There is another (C{0x08}) but not documented at this time because how/why
    it is used is unclear.

    L{versionSuccess} must be called to move on to stage 2.

    Stage 2 - Handshake negotiations::

    The next 1536 * 2 bytes is handshaking data. This part is delegated to a
    handshake negotiator, which is based on the protocol version.

    L{handshakeSuccess} must be called to move on to stage 3.

    Stage 3 - RTMP Message streaming::


    Some docstring here.

    @ivar state: The state of the protocol.
    """

    STATE_VERSION = 'version'
    STATE_HANDSHAKE = 'handshake'
    STATE_STREAM = 'stream'

    state = None
    protocolVersion = 3

    def connectionMade(self):
        """
        Called when this a connection has been made.
        """
        self.state = self.STATE_VERSION

        self.startVersioning()

    def connectionLost(self, reason):
        """
        Called when the connection has been lost.

        @param reason: The reason for the disconnection
        """
        if self.state == self.STATE_VERSION:
            self.stopVersioning(reason)
        elif self.state == self.STATE_HANDSHAKE:
            self.stopHandshaking(reason)
        elif self.state == self.STATE_STREAM:
            self.stopStreaming(reason)

    def dataReceived(self, data):
        """
        """
        if self.state == self.STATE_VERSION:
            self.version_dataReceived(data)
        elif self.state == self.STATE_HANDSHAKE:
            self.handshake_dataReceived(data)
        elif self.state == self.STATE_STREAM:
            BaseStreamer.dataReceived(self, data)
        else:
            raise RuntimeError('Invalid state!')

    def startVersioning(self):
        """
        Start protocol version negotiations.
        """
        self.buffer = BufferedByteStream()

    def stopVersioning(self, reason=None):
        """
        Stop protocol version negotiations.

        @param reason: A L{failure.Failure} object if protocol version
            negotiations failed. C{None} means success.
        """
        del self.buffer

    def version_dataReceived(self, data):
        """
        """
        if not data:
            return

        self.buffer.append(data)

        self.peerProtocolVersion = self.buffer.read_uchar()

        self.versionReceived(self.peerProtocolVersion)

    def versionReceived(self, version):
        """
        Called when the peers' protocol version has been received.

        The default behaviour is to accept any known version. It is the
        responsibility for any overriding subclass to call L{versionSuccess} for
        negotiations to proceed.
        """
        if version == self.protocolVersion:
            self.versionSuccess()

            return

        raise UnknownProtocolVersion('Unhandled protocol version %d' %
                                     (version, ))

    def versionSuccess(self):
        """
        Protocol version negotiations have been successful, now on to
        handshaking.
        """
        try:
            data = self.buffer.read()
        except IOError:
            data = None

        self.stopVersioning()

        self.state = self.STATE_HANDSHAKE

        self.startHandshaking()

        if data:
            # any data that was left over from version negotiations is
            # artificially re-inserted back into the protocol because the
            # `state` has changed.
            self.dataReceived(data)

    def buildHandshakeNegotiator(self):
        """
        """
        raise NotImplementedError

    def startHandshaking(self):
        """
        """
        self.handshaker = self.buildHandshakeNegotiator()

        # TODO: apply uptime, version to the handshaker instead of 0, 0
        self.handshaker.start(0, 0)

    def stopHandshaking(self, reason=None):
        """
        """
        del self.handshaker

    def handshake_dataReceived(self, data):
        """
        """
        self.handshaker.dataReceived(data)

    def handshakeSuccess(self, data):
        """
        Handshaking was successful, streaming now commences.
        """
        #data = self.handshaker.getRemainingData()

        self.stopHandshaking()

        self.state = self.STATE_STREAM

        self.startStreaming()

        if data:
            self.dataReceived(data)

    def startStreaming(self):
        """
        Because Python is awesome we can short circuit checking state each time
        L{dataReceived} is called.
        """
        self.dataReceived = lambda x: BaseStreamer.dataReceived(self, x)

        return BaseStreamer.startStreaming(self)
Exemple #16
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class RTMPDisassembler(object):
    """
    Disassembling bytestream into RTMP packets.

    RTMP stream slices packets into chunks of L{chunkSize}. This class
    processes incoming stream of RTMP protocol data (after initial handshake)
    and decodes RTMP packets.

    Communication goes independently for each object_id. Last received
    headers are stored for each object_id in L{lastHeaders}. L{pool} holds
    incomplete packet contents also for each object_id.

    @ivar lastHeaders: last received header for object_id
    @type lastHeaders: C{dict}, object_id -> L{RTMPHeader}
    @ivar pool: incomplete packet data for object_id
    @type pool: C{dict}, object_id -> L{BufferedByteStream}
    @ivar chunkSize: size of chunk for this stream
    @type chunkSize: C{int}
    @ivar buffer: incoming buffer with data received from protocol
    @type buffer: L{BufferedByteStream}
    """
    def __init__(self, chunkSize):
        """
        Constructor.

        @param chunkSize: initial size of chunk
        @type chunkSize: C{int}
        """
        self.lastHeaders = {}
        self.pool = {}
        self.chunkSize = chunkSize
        self.buffer = BufferedByteStream()

    def push_data(self, data):
        """
        Push more incoming data.

        @param data: data received
        @type data: C{str}
        """
        self.buffer.seek(0, 2)
        self.buffer.write(data)

        return self

    def disassemble(self):
        """
        Disassemble L{buffer} into packets.

        Returns first decoded packet or None, if no packet could
        be decoded at the moment.

        @return: decoded packet
        @rtype: L{Packet}
        """
        self.buffer.seek(0)

        while self.buffer.remaining() > 0:
            try:
                # try to parse header from stream
                header = RTMPHeader.read(self.buffer)
            except NeedBytes, (bytes, ):
                # not enough bytes, return what we've already parsed
                return None

            # fill header with extra data from previous headers received
            # with same object_id
            header.fill(self.lastHeaders.get(header.object_id, RTMPHeader()))

            # get buffer for data of this packet
            buf = self.pool.get(header.object_id, BufferedByteStream())

            # this chunk size is minimum of regular chunk size in this
            # disassembler and what we have left here
            thisChunk = min(header.length - len(buf), self.chunkSize)
            if self.buffer.remaining() < thisChunk:
                # we have not enough bytes to read this chunk of data
                return None

            # we got complete chunk
            buf.write(self.buffer.read(thisChunk))

            # store packet header for this object_id
            self.lastHeaders[header.object_id] = header

            # skip data left in input buffer
            self.buffer.consume()

            # this chunk completes full packet?
            if len(buf) < header.length:
                # no, store buffer for further chunks
                self.pool[header.object_id] = buf
            else:
                # parse packet from header and data
                buf.seek(0, 0)

                # delete stored data for this packet
                if header.object_id in self.pool:
                    del self.pool[header.object_id]

                return self._decode_packet(header, buf)

        return None