我正在用python为redis集群编写cron脚本,并使用redis-py-cluster只从prod服务器读取数据。一个单独的java应用程序正在使用snappy压缩和java字符串编解码器utf-8编写redis集群。
我能读数据,但不能解码。
from rediscluster import RedisCluster
import snappy
host, port ="127.0.0.1", "30001"
startup_nodes = [{"host": host, "port": port}]
print("Trying connecting to redis cluster host=" + host + ", port=" + str(port))
rc = RedisCluster(startup_nodes=startup_nodes, max_connections=32, decode_responses=True)
print("Connected", rc)
print("Reading all keys, value ...\n\n")
for key in rc.scan_iter("uidx:*"):
value = rc.get(key)
#uncompress = snappy.uncompress(value, decoding="utf-8")
print(key, value)
print('\n')
print("Done. exit()")
exit()
``` `decode_responses=False` 对这个评论没问题。然而,变化 `decode_responses=True` 正在抛出错误。我的猜测是它不能得到正确的解码器。
Traceback (most recent call last):
File "splooks_cron.py", line 22, in
print(key, rc.get(key))
File "/Library/Python/2.7/site-packages/redis/client.py", line 1207, in get
return self.execute_command('GET', name)
File "/Library/Python/2.7/site-packages/rediscluster/utils.py", line 101, in inner
return func(*args,**kwargs)
File "/Library/Python/2.7/site-packages/rediscluster/client.py", line 410, in execute_command
return self.parse_response(r, command,**kwargs)
File "/Library/Python/2.7/site-packages/redis/client.py", line 768, in parse_response
response = connection.read_response()
File "/Library/Python/2.7/site-packages/redis/connection.py", line 636, in read_response
raise e
: 'utf8' codec can't decode byte 0x82 in position 0: invalid start byte
ps:取消对此行的注解 `uncompress = snappy.uncompress(value, decoding="utf-8")` 因为错误而中断
Traceback (most recent call last):
File "splooks_cron.py", line 27, in
uncompress = snappy.uncompress(value, decoding="utf-8")
File "/Library/Python/2.7/site-packages/snappy/snappy.py", line 91, in uncompress
return _uncompress(data).decode(decoding)
snappy.UncompressError: Error while decompressing: invalid input
1条答案
按热度按时间cig3rfwq1#
经过几个小时的调试,我终于解决了这个问题。
我在编写redis集群的java代码中使用了xerial/snappyjava压缩器。有趣的是在压缩过程中
SnappyOutputStream
在压缩数据的开头添加一些偏移量。在我的情况下,这个看起来像这样由于这个原因,减压器无法计算。我修改了如下代码,并从值中删除了偏移量。现在很好用。