python tempfile | NamedTemporaryFile can't use generated tempfile
Question:
I would like to load the temp file to make changes or just be able to upload it somewhere,
When I try to do so – It throws an error as shown below
I have set the permission to w+ – which should ideally allow me to read and write, Not sure what am I missing here – Any help would be appreciated – thanks
>>> from openpyxl import load_workbook
>>> from tempfile import NamedTemporaryFile
>>> import os
>>> with NamedTemporaryFile(suffix=".xlsx", mode='w+', delete=True) as tmp:
... temp_path = tmp.name
... os.path.exists(temp_path)
... wb = load_workbook(temp_path)
...
True
Traceback (most recent call last):
File "<stdin>", line 4, in <module>
File "C:Usersmy_nameVS_PROJECTS.venvlibsite-packagesopenpyxlreaderexcel.py", line 315, in load_workbook
reader = ExcelReader(filename, read_only, keep_vba,
File "C:Usersmy_nameVS_PROJECTS.venvlibsite-packagesopenpyxlreaderexcel.py", line 124, in __init__
self.archive = _validate_archive(fn)
File "C:Usersmy_nameVS_PROJECTS.venvlibsite-packagesopenpyxlreaderexcel.py", line 96, in _validate_archive
archive = ZipFile(filename, 'r')
File "C:Program FilesWindowsAppsPythonSoftwareFoundation.Python.3.8_3.8.2288.0_x64__qbz5n2kfra8p0libzipfile.py", line 1251, in __init__
self.fp = io.open(file, filemode)
PermissionError: [Errno 13] Permission denied: 'C:\Users\my_name\AppData\Local\Temp\tmp5dsrqegj.xlsx'
Answers:
You’re on Windows, evidently.
On Windows, you can’t open another handle to a O_TEMPORARY file while it’s still open (see e.g. https://github.com/bravoserver/bravo/issues/111, https://docs.python.org/3/library/tempfile.html#tempfile.NamedTemporaryFile, https://bugs.python.org/issue14243).
You’ll need to use delete=False
and clean up manually, e.g.
try:
tmp = NamedTemporaryFile(suffix=".xlsx", mode='w+', delete=False)
tmp.close()
temp_name = tmp.name
os.path.exists(temp_path)
wb = load_workbook(temp_path)
finally:
try:
os.unlink(temp_name)
except Exception:
pass
I am using this helper to wrap AKX’s solution:
class WritableTempFile:
"""
Avoid "Permission denied error" on Windows:
with tempfile.NamedTemporaryFile("w", suffix=".gv") as temp_file:
# Not writable on Windows:
# https://docs.python.org/3/library/tempfile.html#tempfile.NamedTemporaryFile
Example:
with WritableTempFile("w", suffix=".gv") as temp_file:
tree.to_dotfile(temp_file.name)
"""
def __init__(self, mode="w", *, encoding=None, suffix=None):
self.mode = mode
self.encoding = encoding
self.suffix = suffix
def __enter__(self):
self.temp_file = tempfile.NamedTemporaryFile(
self.mode, encoding=self.encoding, suffix=self.suffix, delete=False
)
return self.temp_file
def __exit__(self, exc_type, exc_val, exc_tb):
self.temp_file.close()
os.unlink(self.temp_file.name)
I would like to load the temp file to make changes or just be able to upload it somewhere,
When I try to do so – It throws an error as shown below
I have set the permission to w+ – which should ideally allow me to read and write, Not sure what am I missing here – Any help would be appreciated – thanks
>>> from openpyxl import load_workbook
>>> from tempfile import NamedTemporaryFile
>>> import os
>>> with NamedTemporaryFile(suffix=".xlsx", mode='w+', delete=True) as tmp:
... temp_path = tmp.name
... os.path.exists(temp_path)
... wb = load_workbook(temp_path)
...
True
Traceback (most recent call last):
File "<stdin>", line 4, in <module>
File "C:Usersmy_nameVS_PROJECTS.venvlibsite-packagesopenpyxlreaderexcel.py", line 315, in load_workbook
reader = ExcelReader(filename, read_only, keep_vba,
File "C:Usersmy_nameVS_PROJECTS.venvlibsite-packagesopenpyxlreaderexcel.py", line 124, in __init__
self.archive = _validate_archive(fn)
File "C:Usersmy_nameVS_PROJECTS.venvlibsite-packagesopenpyxlreaderexcel.py", line 96, in _validate_archive
archive = ZipFile(filename, 'r')
File "C:Program FilesWindowsAppsPythonSoftwareFoundation.Python.3.8_3.8.2288.0_x64__qbz5n2kfra8p0libzipfile.py", line 1251, in __init__
self.fp = io.open(file, filemode)
PermissionError: [Errno 13] Permission denied: 'C:\Users\my_name\AppData\Local\Temp\tmp5dsrqegj.xlsx'
You’re on Windows, evidently.
On Windows, you can’t open another handle to a O_TEMPORARY file while it’s still open (see e.g. https://github.com/bravoserver/bravo/issues/111, https://docs.python.org/3/library/tempfile.html#tempfile.NamedTemporaryFile, https://bugs.python.org/issue14243).
You’ll need to use delete=False
and clean up manually, e.g.
try:
tmp = NamedTemporaryFile(suffix=".xlsx", mode='w+', delete=False)
tmp.close()
temp_name = tmp.name
os.path.exists(temp_path)
wb = load_workbook(temp_path)
finally:
try:
os.unlink(temp_name)
except Exception:
pass
I am using this helper to wrap AKX’s solution:
class WritableTempFile:
"""
Avoid "Permission denied error" on Windows:
with tempfile.NamedTemporaryFile("w", suffix=".gv") as temp_file:
# Not writable on Windows:
# https://docs.python.org/3/library/tempfile.html#tempfile.NamedTemporaryFile
Example:
with WritableTempFile("w", suffix=".gv") as temp_file:
tree.to_dotfile(temp_file.name)
"""
def __init__(self, mode="w", *, encoding=None, suffix=None):
self.mode = mode
self.encoding = encoding
self.suffix = suffix
def __enter__(self):
self.temp_file = tempfile.NamedTemporaryFile(
self.mode, encoding=self.encoding, suffix=self.suffix, delete=False
)
return self.temp_file
def __exit__(self, exc_type, exc_val, exc_tb):
self.temp_file.close()
os.unlink(self.temp_file.name)