Files
deb-python-kafka/kafka/util.py
Mahendra M 2c257eeb1f PEP8-ify most of the files
consumer.py and conn.py will be done later after pending merges
2013-05-29 16:38:39 -04:00

100 lines
2.2 KiB
Python

from collections import defaultdict
from itertools import groupby
import struct
from threading import Timer
def write_int_string(s):
if s is None:
return struct.pack('>i', -1)
else:
return struct.pack('>i%ds' % len(s), len(s), s)
def write_short_string(s):
if s is None:
return struct.pack('>h', -1)
else:
return struct.pack('>h%ds' % len(s), len(s), s)
def read_short_string(data, cur):
if len(data) < cur + 2:
raise BufferUnderflowError("Not enough data left")
(strLen,) = struct.unpack('>h', data[cur:cur + 2])
if strLen == -1:
return (None, cur + 2)
cur += 2
if len(data) < cur + strLen:
raise BufferUnderflowError("Not enough data left")
out = data[cur:cur + strLen]
return (out, cur + strLen)
def read_int_string(data, cur):
if len(data) < cur + 4:
raise BufferUnderflowError("Not enough data left")
(strLen,) = struct.unpack('>i', data[cur:cur + 4])
if strLen == -1:
return (None, cur + 4)
cur += 4
if len(data) < cur + strLen:
raise BufferUnderflowError("Not enough data left")
out = data[cur:cur + strLen]
return (out, cur + strLen)
def relative_unpack(fmt, data, cur):
size = struct.calcsize(fmt)
if len(data) < cur + size:
raise BufferUnderflowError("Not enough data left")
out = struct.unpack(fmt, data[cur:cur + size])
return (out, cur + size)
def group_by_topic_and_partition(tuples):
out = defaultdict(dict)
for t in tuples:
out[t.topic][t.partition] = t
return out
class BufferUnderflowError(Exception):
pass
class ChecksumError(Exception):
pass
class ReentrantTimer(object):
"""
A timer that can be restarted, unlike threading.Timer
(although this uses threading.Timer)
t: timer interval in milliseconds
fn: a callable to invoke
"""
def __init__(self, t, fn):
self.timer = None
self.t = t
self.fn = fn
def start(self):
if self.timer is not None:
self.timer.cancel()
self.timer = Timer(self.t / 1000., self.fn)
self.timer.start()
def stop(self):
self.timer.cancel()
self.timer = None