class Channel(object):
COMPRESSION_THRESHOLD = 3000
COMPRESSION_LEVEL = 1
FRAME_HEADER = Struct("!LB")
FLUSHER = "\n" # cause any line-buffered layers below us to flush
__slots__ = ["stream", "compress"]
def __init__(self, stream, compress=True):
self.stream = stream
if not zlib:
compress = False
self.compress = compress
def close(self):
self.stream.close()
@property
def closed(self):
return self.stream.closed
def fileno(self):
return self.stream.fileno()
def poll(self, timeout):
return self.stream.poll(timeout)
def recv(self):
header = self.stream.read(self.FRAME_HEADER.size)
length, compressed = self.FRAME_HEADER.unpack(header)
data = self.stream.read(length +
len(self.FLUSHER))[:-len(self.FLUSHER)]
if compressed:
data = zlib.decompress(data)
return data
def send(self, data):
if self.compress and len(data) > self.COMPRESSION_THRESHOLD:
compressed = 1
data = zlib.compress(data, self.COMPRESSION_LEVEL)
else:
compressed = 0
header = self.FRAME_HEADER.pack(len(data), compressed)
buf = header + data + self.FLUSHER
self.stream.write(buf)
class Channel(object):
"""Channel implementation.
Note: In order to avoid problems with all sorts of line-buffered transports,
we deliberately add ``\\n`` at the end of each frame.
"""
COMPRESSION_THRESHOLD = 3000
COMPRESSION_LEVEL = 1
FRAME_HEADER = Struct("!LB")
FLUSHER = BYTES_LITERAL(
"\n") # cause any line-buffered layers below us to flush
__slots__ = ["stream", "compress"]
def __init__(self, stream, compress=True):
self.stream = stream
if not zlib:
compress = False
self.compress = compress
def close(self):
"""closes the channel and underlying stream"""
self.stream.close()
@property
def closed(self):
"""indicates whether the underlying stream has been closed"""
return self.stream.closed
def fileno(self):
"""returns the file descriptor of the underlying stream"""
return self.stream.fileno()
def poll(self, timeout):
"""polls the underlying steam for data, waiting up to *timeout* seconds"""
return self.stream.poll(timeout)
def recv(self):
"""Receives the next packet (or *frame*) from the underlying stream.
This method will block until the packet has been read completely
:returns: string of data
"""
header = self.stream.read(self.FRAME_HEADER.size)
length, compressed = self.FRAME_HEADER.unpack(header)
data = self.stream.read(length +
len(self.FLUSHER))[:-len(self.FLUSHER)]
if compressed:
data = zlib.decompress(data)
return data
def send(self, data):
"""Sends the given string of data as a packet over the underlying
stream. Blocks until the packet has been sent.
:param data: the byte string to send as a packet
"""
if self.compress and len(data) > self.COMPRESSION_THRESHOLD:
compressed = 1
data = zlib.compress(data, self.COMPRESSION_LEVEL)
else:
compressed = 0
header = self.FRAME_HEADER.pack(len(data), compressed)
buf = header + data + self.FLUSHER
self.stream.write(buf)
TAG_STR_L4 = b"\x0f"
TAG_TUP1 = b"\x10"
TAG_TUP2 = b"\x11"
TAG_TUP3 = b"\x12"
TAG_TUP4 = b"\x13"
TAG_TUP_L1 = b"\x14"
TAG_TUP_L4 = b"\x15"
TAG_INT_L1 = b"\x16"
TAG_INT_L4 = b"\x17"
TAG_FLOAT = b"\x18"
TAG_SLICE = b"\x19"
TAG_FSET = b"\x1a"
TAG_COMPLEX = b"\x1b"
IMM_INTS = dict((i, bytes([i + 0x50])) for i in range(-0x30, 0xa0))
I1 = Struct("!B")
I4 = Struct("!L")
F8 = Struct("!d")
C16 = Struct("!dd")
_dump_registry = {}
_load_registry = {}
IMM_INTS_LOADER = dict((v, k) for k, v in IMM_INTS.items())
def register(coll, key):
def deco(func):
coll[key] = func
return func
return deco