使用"tarfile"提取存档时出错

Question

我在尝试使用tarfile库提取.tar.gz存档时遇到错误。

以下是相关的代码片段：

# `gzip_archive_bytes_content` is the content of the gzip archive, in "bytes" format
repo_sources_file_object = io.BytesIO(gzip_archive_bytes_content)
repo_sources_tar_object = tarfile.TarFile(fileobj=repo_sources_file_object)
repo_sources_tar_object.extractall(path="/tmp/")

这是我得到的错误：

Traceback (most recent call last):
File "/usr/local/lib/python3.7/tarfile.py", line 186, in nti
s = nts(s, "ascii", "strict")
File "/usr/local/lib/python3.7/tarfile.py", line 170, in nts
return s.decode(encoding, errors)
UnicodeDecodeError: 'ascii' codec can't decode byte 0x9a in position 1: ordinal not in range(128)
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "/usr/local/lib/python3.7/tarfile.py", line 2289, in next
tarinfo = self.tarinfo.fromtarfile(self)
File "/usr/local/lib/python3.7/tarfile.py", line 1095, in fromtarfile
obj = cls.frombuf(buf, tarfile.encoding, tarfile.errors)
File "/usr/local/lib/python3.7/tarfile.py", line 1037, in frombuf
chksum = nti(buf[148:156])
File "/usr/local/lib/python3.7/tarfile.py", line 189, in nti
raise InvalidHeaderError("invalid header")
tarfile.InvalidHeaderError: invalid header
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "/usr/local/lib/python3.7/runpy.py", line 193, in _run_module_as_main
"__main__", mod_spec)
File "/usr/local/lib/python3.7/runpy.py", line 85, in _run_code
exec(code, run_globals)
File "/usr/local/lib/python3.7/site-packages/my-package/__main__.py", line 87, in <module>
function(**function_args)
File "/usr/local/lib/python3.7/site-packages/my-package/chart.py", line 107, in reinstall
install()
File "/usr/local/lib/python3.7/site-packages/my-package/chart.py", line 89, in install
repo_sources_tar_object = tarfile.TarFile(fileobj=repo_sources_file_object)
File "/usr/local/lib/python3.7/tarfile.py", line 1484, in __init__
self.firstmember = self.next()
File "/usr/local/lib/python3.7/tarfile.py", line 2301, in next
raise ReadError(str(e))
tarfile.ReadError: invalid header

蟒蛇版本：3.7

Answer 1

我从直接实例化tarfile.TarFile对象切换到使用tarfile.open()构造函数，它修复了它：

repo_sources_tar_object = tarfile.open(fileobj=repo_sources_file_object)

文档中实际上有一个警告，在这里：

不要直接使用这个类：改用tarfile.open((。

Answer 2

最佳做法是使用上下文管理器，以便在作业完成后自动关闭文件。

可以这样写：

import contextlib
import io
import tarfile
gzip_archive_bytes_content = b"..."
repo_sources_file_object = io.BytesIO(gzip_archive_bytes_content)
with contextlib.closing(tarfile.open(fileobj=repo_sources_file_object)) as arch:
arch.extractall(path="/tmp/")

这在tarfile.TarFile可用，但不适用于tarfile.open()。 所以你可以写：

with tarfile.TarFile(...) as arch:
...