Python gzip CRC检查失败
我有一个包含大量文本文件的文件夹。每一个都是gzip,重数千兆字节。 我编写了一段代码来分割每个gzip文件的内容:每个gzip文件都是用Python gzip CRC检查失败,python,gzip,python-multiprocessing,crc,Python,Gzip,Python Multiprocessing,Crc,我有一个包含大量文本文件的文件夹。每一个都是gzip,重数千兆字节。 我编写了一段代码来分割每个gzip文件的内容:每个gzip文件都是用gzip打开的,然后每个指定的行块都被读写到一个新的gzip文件中 以下是文件file_compression.py中的代码: import sys, os, file_manipulation as fm import gzip def splitGzipFile(fileName, dest=None, chunkPerSplit=100, lineP
gzip
打开的,然后每个指定的行块都被读写到一个新的gzip文件中
以下是文件file_compression.py
中的代码:
import sys, os, file_manipulation as fm
import gzip
def splitGzipFile(fileName, dest=None, chunkPerSplit=100, linePerChunk=4, file_field_separator="_", zfill=3
, verbose=False, file_permission=None, execute=True):
"""
Splits a gz file into chunk files.
:param fileName:
:param chunkPerSplit:
:param linePerChunk:
:return:
"""
absPath = os.path.abspath(fileName)
baseName = os.path.basename(absPath)
dirName = os.path.dirname(absPath)
destFolder = dirName if dest is None else dest
## Compute file fields
rawBaseName, extensions = baseName.split(os.extsep, 1)
if not str(extensions).startswith("."):
extensions = "." + extensions
file_fields = str(rawBaseName).split(file_field_separator)
first_fields = file_fields[:-1] if file_fields.__len__() > 1 else file_fields
first_file_part = file_field_separator.join(first_fields)
last_file_field = file_fields[-1] if file_fields.__len__() > 1 else ""
current_chunk = getCurrentChunkNumber(last_file_field)
if current_chunk is None or current_chunk < 0:
first_file_part = rawBaseName
## Initialize chunk variables
linePerSplit = chunkPerSplit * linePerChunk
# chunkCounter = 0
chunkCounter = 0 if current_chunk is None else current_chunk-1
for chunk in getFileChunks(fileName, linePerSplit):
print "writing " + str(str(chunk).__len__()) + " ..."
chunkCounter += 1
oFile = fm.buildPath(destFolder) + first_file_part + file_field_separator + str(chunkCounter).zfill(zfill) + extensions
if execute:
writeGzipFile(oFile, chunk, file_permission)
if verbose:
print "Splitting: created file ", oFile
def getCurrentChunkNumber(chunk_field):
"""
Tries to guess an integer from a string.
:param chunk_field:
:return: an integer, None if failure.
"""
try:
return int(chunk_field)
except ValueError:
return None
def getFileChunks(fileName, linePerSplit):
with gzip.open(fileName, 'rb') as f:
print "gzip open"
lineCounter = 0
currentChunk = ""
for line in f:
currentChunk += line
lineCounter += 1
if lineCounter >= linePerSplit:
yield currentChunk
currentChunk = ""
lineCounter = 0
if not currentChunk == '':
yield currentChunk
def writeGzipFile(file_name, content, file_permission=None):
import gzip
with gzip.open(file_name, 'wb') as f:
if not content == '':
f.write(content)
if file_permission is not None and type(file_permission) == int:
os.chmod(file_name, file_permission)
到目前为止,代码一直运行良好。但今天我遇到了gzip文件CRC损坏的问题:
Process Process-3:72:
Traceback (most recent call last):
...
File "/.../tools/file_utils/file_compression.py", line 43, in splitGzipFile
for chunk in getFileChunks(fileName, linePerSplit):
File "/.../tools/file_utils/file_compression.py", line 70, in getFileChunks
for line in f:
File "/.../python2.7/lib/python2.7/gzip.py", line 450, in readline
c = self.read(readsize)
File "/.../python2.7/lib/python2.7/gzip.py", line 256, in read
self._read(readsize)
File "/.../python2.7/lib/python2.7/gzip.py", line 320, in _read
self._read_eof()
File "/.../python2.7/lib/python2.7/gzip.py", line 342, in _read_eof
hex(self.crc)))
IOError: CRC check failed 0xddbb6045 != 0x34fd5580L
这个问题的根源可能是什么?我必须再次声明,到目前为止,它已经做到了
始终工作,文件夹和文件始终具有相同的结构。这个例子中的区别可能是我的脚本处理的gzip文件比平时多,可能是平时的两倍
这可能是同一时间访问相同文件的问题吗?但是,我非常怀疑,我通过在我的split_Seed列表中注册访问的每个文件来确保情况并非如此
我愿意接受任何暗示,因为我没有更多的线索去哪里寻找
编辑1
可能是其他人或其他程序访问了某些打开的文件?我不能要求和依赖证明。因此,首先,如果我放置一个
多进程.Lock
,它会阻止任何其他线程、进程、程序、用户等修改该文件吗?还是只限于Python?我在上面找不到任何文档。我在运行了几个月的代码上遇到了完全相同的错误。结果表明,该特定文件的文件源已损坏。我回到一个旧文件,它工作正常,我使用了一个新文件,它也工作正常。我也有同样的问题。我刚刚删除了旧文件,重新运行了代码
rm-rf/tmp/imagenet/
您是否检查了文件名为fileName
的文件是否因使用gunzip
而损坏?
Process Process-3:72:
Traceback (most recent call last):
...
File "/.../tools/file_utils/file_compression.py", line 43, in splitGzipFile
for chunk in getFileChunks(fileName, linePerSplit):
File "/.../tools/file_utils/file_compression.py", line 70, in getFileChunks
for line in f:
File "/.../python2.7/lib/python2.7/gzip.py", line 450, in readline
c = self.read(readsize)
File "/.../python2.7/lib/python2.7/gzip.py", line 256, in read
self._read(readsize)
File "/.../python2.7/lib/python2.7/gzip.py", line 320, in _read
self._read_eof()
File "/.../python2.7/lib/python2.7/gzip.py", line 342, in _read_eof
hex(self.crc)))
IOError: CRC check failed 0xddbb6045 != 0x34fd5580L