zip downloaded csv file - python

I'm trying to download a csv file and zip it before saving it.
The code I'm using is:
req = urllib2.Request(url)
fh = urllib2.urlopen(req)
with contextlib.closing(ZipFile("test.csv.zip", "w", zipfile.ZIP_STORED)) as f:
f.write(fh.read())
f.close()
What this does is to print the contents of the csv file to stdout and create an empty zipfile.
Any ideas of what could be wrong?
Thanks,
Isaac

Take a look at the documentation for ZipFile.write(). Here is the function signature:
ZipFile.write(filename[, arcname[, compress_type]])
The first argument should be the file name of the file that you are adding to the zip archive, not the contents of the file. Instead you are passing the entire contents of the downloaded resource as the file name and, because that will likely be illegal (too long), you see the file contents dumped as part of the error message of the raised exception.
To fix this you need to use is ZipFile.writestr():
req = urllib2.Request(url)
fh = urllib2.urlopen(req)
with ZipFile("test.csv.zip", "w", zipfile.ZIP_STORED) as f:
f.writestr('test.csv', fh.read())
If it is your intention to compress only a single file, you probably don't need to use a zip archive, and you might be better off using gzip or bzip2.

Related

Python write file content from requests response to corresponding file

I have an API service which responds with the file content in byte string and extension of the file. I need to write this response to the corresponding file based on the extension. The problem is I have to work with a lot of file types including pdf, pkl, sav, csv etc. I can't find a generic solution to tackle this problem
for csv files I am doing:
data = response.content.decode('utf-8').splitlines()
print(data)
import csv,re
with open("tet.csv", "w") as csv_file:
writer = csv.writer(csv_file, delimiter = '\t')
for line in data:
writer.writerow(re.split('\s+',line))
for pdf files:
with open('hh.pdf','wb') as fd:
fd.write(oR.content)
cant seem to get a generic solution to tackle this problem.
Any help is appeciated. Thanks in advance
The incoming response.content from api is of binary format, so irrespective of file type it just needs to be written in the binary format
with open(f'file.{extension}', 'w+b') as f:
f.write(res.content)

How to read contents of zip file in memory on a file upload in python?

I have a zip file that I receive when the user uploads a file. The zip essentially contains a json file which I want to read and process without having to create the zip file first, then unzipping it and then reading the content of the inner file.
Currently I only the longer process which is something like below
import json
import zipfile
#csrf_exempt
def get_zip(request):
try:
if request.method == "POST":
try:
client_file = request.FILES['file']
file_path = "/some/path/"
# first dump the zip file to a directory
with open(file_path + '%s' % client_file.name, 'wb+') as dest:
for chunk in client_file.chunks():
dest.write(chunk)
# unzip the zip file to the same directory
with zipfile.ZipFile(file_path + client_file.name, 'r') as zip_ref:
zip_ref.extractall(file_path)
# at this point we get a json file from the zip say `test.json`
# read the json file content
with open(file_path + "test.json", "r") as fo:
json_content = json.load(fo)
doSomething(json_content)
return HttpResponse(0)
except Exception as e:
return HttpResponse(1)
As you can see, this involves 3 steps to finally get the content from the zip file into memory. What I want is get the content of the zip file and load directly into memory.
I did find some similar questions in stack overflow like this one https://stackoverflow.com/a/2463819 . But I am not sure at what point do I invoke this operation mentioned in the post
How can I achieve this?
Note: I am using django in backend.
There will always be one json file in the zip.
From what I understand, what #jason is trying to say here is to first open a zipFile just like you have done here with zipfile.ZipFile(file_path + client_file.name, 'r') as zip_ref:.
class zipfile.ZipFile(file[, mode[, compression[, allowZip64]]])
Open a ZIP file, where file can be either a path to a file (a string) or a file-like object.
And then use BytesIO read in the bytes of a file-like object. But from above you are reading in r mode and not rb mode. So change it as follows.
with open(filename, 'rb') as file_data:
bytes_content = file_data.read()
file_like_object = io.BytesIO(bytes_content)
zipfile_ob = zipfile.ZipFile(file_like_object)
Now zipfile_ob can be accessed from memory.
The first argument to zipfile.ZipFile() can be a file object rather than a pathname. I think the Django UploadedFile object supports this use, so you can read directly from that rather than having to copy into a file.
You can also open the file directly from the zip archive rather than extracting that into a file.
import json
import zipfile
#csrf_exempt
def get_zip(request):
try:
if request.method == "POST":
try:
client_file = request.FILES['file']
# unzip the zip file to the same directory
with zipfile.ZipFile(client_file, 'r') as zip_ref:
first = zip_ref.infolist()[0]
with zip_ref.open(first, "r") as fo:
json_content = json.load(fo)
doSomething(json_content)
return HttpResponse(0)
except Exception as e:
return HttpResponse(1)

Download a file in python with urllib2 instead of urllib

I'm trying to download a tarball file and save it locally with python. With urllib it's pretty simple:
import urllib
urllib2.urlopen(url, 'compressed_file.tar.gz')
tar = tarfile.open('compressed_file.tar.gz')
print tar.getmembers()
So my question is really simple: What's the way to achieve this using the urllib2 library?
Quoting docs:
urllib2.urlopen(url[, data[, timeout[, cafile[, capath[, cadefault[,
context]]]]])
Open the URL url, which can be either a string or a
Request object.
data may be a string specifying additional data to send to the server, or None if no such data is needed.
Nothing in urlopen interface documentation says, that second argument is a name of file where response should be written.
You need to explicitly write data read from response to file:
r = urllib2.urlopen(url)
CHUNK_SIZE = 1 << 20
with open('compressed_file.tar.gz', 'wb') as f:
# line belows downloads all file at once to memory, and dumps it to file afterwards
# f.write(r.read())
# below is preferable lazy solution - download and write data in chunks
while True:
chunk = r.read(CHUNK_SIZE)
if not chunk:
break
f.write(chunk)

How to read zip file content without unzipping (in compressed format) using Python

I have to publish a zip file to the server. This involves reading the file and uploading.
zfile=zipfile.ZipFile(x,"r")
data = zfile.read()
zfile.close()
This won't work as read() needs an additional argument-filename to uncompress.
You may ignore the fact the file is a ZIP file and open it as you would any file:
with open(x, "rb") as zfile:
data = zfile.read()

unzipping file results in "BadZipFile: File is not a zip file"

I have two zip files, both of them open well with Windows Explorer and 7-zip.
However when i open them with Python's zipfile module [ zipfile.ZipFile("filex.zip") ], one of them gets opened but the other one gives error "BadZipfile: File is not a zip file".
I've made sure that the latter one is a valid Zip File by opening it with 7-Zip and looking at its properties (says 7Zip.ZIP). When I open the file with a text editor, the first two characters are "PK", showing that it is indeed a zip file.
I'm using Python 2.5 and really don't have any clue how to go about for this. I've tried it both with Windows as well as Ubuntu and problem exists on both platforms.
Update: Traceback from Python 2.5.4 on Windows:
Traceback (most recent call last):
File "<module1>", line 5, in <module>
zipfile.ZipFile("c:/temp/test.zip")
File "C:\Python25\lib\zipfile.py", line 346, in init
self._GetContents()
File "C:\Python25\lib\zipfile.py", line 366, in _GetContents
self._RealGetContents()
File "C:\Python25\lib\zipfile.py", line 378, in _RealGetContents
raise BadZipfile, "File is not a zip file"
BadZipfile: File is not a zip file
Basically when the _EndRecData function is called for getting data from End of Central Directory" record, the comment length checkout fails [ endrec[7] == len(comment) ].
The values of locals in the _EndRecData function are as following:
END_BLOCK: 4096,
comment: '\x00',
data: '\xd6\xf6\x03\x00\x88,N8?<e\xf0q\xa8\x1cwK\x87\x0c(\x82a\xee\xc61N\'1qN\x0b\x16K-\x9d\xd57w\x0f\xa31n\xf3dN\x9e\xb1s\xffu\xd1\.....', (truncated)
endrec: ['PK\x05\x06', 0, 0, 4, 4, 268, 199515, 0],
filesize: 199806L,
fpin: <open file 'c:/temp/test.zip', mode 'rb' at 0x045D4F98>,
start: 4073
files named file can confuse python - try naming it something else. if it STILL wont work, try this code:
def fixBadZipfile(zipFile):
f = open(zipFile, 'r+b')
data = f.read()
pos = data.find('\x50\x4b\x05\x06') # End of central directory signature
if (pos > 0):
self._log("Trancating file at location " + str(pos + 22)+ ".")
f.seek(pos + 22) # size of 'ZIP end of central directory record'
f.truncate()
f.close()
else:
# raise error, file is truncated
I run into the same issue. My problem was that it was a gzip instead of a zip file. I switched to the class gzip.GzipFile and it worked like a charm.
astronautlevel's solution works for most cases, but the compressed data and CRCs in the Zip can also contain the same 4 bytes. You should do an rfind (not find), seek to pos+20 and then add write \x00\x00 to the end of the file (tell zip applications that the length of the 'comments' section is 0 bytes long).
# HACK: See http://bugs.python.org/issue10694
# The zip file generated is correct, but because of extra data after the 'central directory' section,
# Some version of python (and some zip applications) can't read the file. By removing the extra data,
# we ensure that all applications can read the zip without issue.
# The ZIP format: http://www.pkware.com/documents/APPNOTE/APPNOTE-6.3.0.TXT
# Finding the end of the central directory:
# http://stackoverflow.com/questions/8593904/how-to-find-the-position-of-central-directory-in-a-zip-file
# http://stackoverflow.com/questions/20276105/why-cant-python-execute-a-zip-archive-passed-via-stdin
# This second link is only losely related, but echos the first, "processing a ZIP archive often requires backwards seeking"
content = zipFileContainer.read()
pos = content.rfind('\x50\x4b\x05\x06') # reverse find: this string of bytes is the end of the zip's central directory.
if pos>0:
zipFileContainer.seek(pos+20) # +20: see secion V.I in 'ZIP format' link above.
zipFileContainer.truncate()
zipFileContainer.write('\x00\x00') # Zip file comment length: 0 byte length; tell zip applications to stop reading.
zipFileContainer.seek(0)
return zipFileContainer
I had the same problem and was able to solve this issue for my files, see my answer at
zipfile cant handle some type of zip data?
I'm very new at python and i was facing the exact same issue, none of the previous methods were working.
Trying to print the 'corrupted' file just before unzipping it returned an empty byte object.
Turned out, I was trying to unzip the file right after writing it to disk, without closing the file handler.
with open(path, 'wb') as outFile:
outFile.write(data)
outFile.close() # was missing this
with zipfile.ZipFile(path, 'r') as zip:
zip.extractall(destination)
Closing the file stream then unzipping the file resolved my issue.
Sometime there are zip file which contain corrupted files and upon unzipping the zip gives badzipfile error. but there are tools like 7zip winrar which ignores these errors and successfully unzip the zip file. you can create a sub process and use this code to unzip your zip file without getting BadZipFile Error.
import subprocess
ziploc = "C:/Program Files/7-Zip/7z.exe" #location where 7zip is installed
cmd = [ziploc, 'e',your_Zip_file.zip ,'-o'+ OutputDirectory ,'-r' ]
sp = subprocess.Popen(cmd, stderr=subprocess.STDOUT, stdout=subprocess.PIPE)
Show the full traceback that you got from Python -- this may give a hint as to what the specific problem is. Unanswered: What software produced the bad file, and on what platform?
Update: Traceback indicates having problem detecting the "End of Central Directory" record in the file -- see function _EndRecData starting at line 128 of C:\Python25\Lib\zipfile.py
Suggestions:
(1) Trace through the above function
(2) Try it on the latest Python
(3) Answer the question above.
(4) Read this and anything else found by google("BadZipfile: File is not a zip file") that appears to be relevant
I faced this problem and was looking for a good and clean solution; But there was no solution until I found this answer. I had the same problem that #marsl (among the answers) had. It was a gzipfile instead of a zipfile in my case.
I could unarchive and decompress my gzipfile with this approach:
with tarfile.open(archive_path, "r:gz") as gzip_file:
gzip_file.extractall()
Have you tried a newer python, or if that is too much trouble, simply a newer zipfile.py? I have successfully used a copy of zipfile.py from Python 2.6.2 (latest at the time) with Python 2.5 in order to open some zip files that weren't supported by Py2.5s zipfile module.
In some cases, you have to confirm if the zip file is actually in gzip format. this was the case for me and i solved it by :
import requests
import tarfile
url = ".tar.gz link"
response = requests.get(url, stream=True)
file = tarfile.open(fileobj=response.raw, mode="r|gz")
file.extractall(path=".")
for this this happened when the file wasn't downloaded fully I think. So I just delete it in my download code.
def download_and_extract(url: str,
path_used_for_zip: Path = Path('~/data/'),
path_used_for_dataset: Path = Path('~/data/tmp/'),
rm_zip_file_after_extraction: bool = True,
force_rewrite_data_from_url_to_file: bool = False,
clean_old_zip_file: bool = False,
gdrive_file_id: Optional[str] = None,
gdrive_filename: Optional[str] = None,
):
"""
Downloads data and tries to extract it according to different protocols/file types.
note:
- to force a download do:
force_rewrite_data_from_url_to_file = True
clean_old_zip_file = True
- to NOT remove file after extraction:
rm_zip_file_after_extraction = False
Tested with:
- zip files, yes!
Later:
- todo: tar, gz, gdrive
force_rewrite_data_from_url_to_file = remvoes the data from url (likely a zip file) and redownloads the zip file.
"""
path_used_for_zip: Path = expanduser(path_used_for_zip)
path_used_for_zip.mkdir(parents=True, exist_ok=True)
path_used_for_dataset: Path = expanduser(path_used_for_dataset)
path_used_for_dataset.mkdir(parents=True, exist_ok=True)
# - download data from url
if gdrive_filename is None: # get data from url, not using gdrive
import ssl
ctx = ssl.create_default_context()
ctx.check_hostname = False
ctx.verify_mode = ssl.CERT_NONE
print("downloading data from url: ", url)
import urllib
import http
response: http.client.HTTPResponse = urllib.request.urlopen(url, context=ctx)
print(f'{type(response)=}')
data = response
# save zipfile like data to path given
filename = url.rpartition('/')[2]
path2file: Path = path_used_for_zip / filename
else: # gdrive case
from torchvision.datasets.utils import download_file_from_google_drive
# if zip not there re-download it or force get the data
path2file: Path = path_used_for_zip / gdrive_filename
if not path2file.exists():
download_file_from_google_drive(gdrive_file_id, path_used_for_zip, gdrive_filename)
filename = gdrive_filename
# -- write downloaded data from the url to a file
print(f'{path2file=}')
print(f'{filename=}')
if clean_old_zip_file:
path2file.unlink(missing_ok=True)
if filename.endswith('.zip') or filename.endswith('.pkl'):
# if path to file does not exist or force to write down the data
if not path2file.exists() or force_rewrite_data_from_url_to_file:
# delete file if there is one if your going to force a rewrite
path2file.unlink(missing_ok=True) if force_rewrite_data_from_url_to_file else None
print(f'about to write downloaded data from url to: {path2file=}')
# wb+ is used sinze the zip file was in bytes, otherwise w+ is fine if the data is a string
with open(path2file, 'wb+') as f:
# with open(path2file, 'w+') as f:
print(f'{f=}')
print(f'{f.name=}')
f.write(data.read())
print(f'done writing downloaded from url to: {path2file=}')
elif filename.endswith('.gz'):
pass # the download of the data doesn't seem to be explicitly handled by me, that is done in the extract step by a magic function tarfile.open
# elif is_tar_file(filename):
# os.system(f'tar -xvzf {path_2_zip_with_filename} -C {path_2_dataset}/')
else:
raise ValueError(f'File type {filename=} not supported.')
# - unzip data written in the file
extract_to = path_used_for_dataset
print(f'about to extract: {path2file=}')
print(f'extract to target: {extract_to=}')
if filename.endswith('.zip'):
import zipfile # this one is for zip files, inspired from l2l
zip_ref = zipfile.ZipFile(path2file, 'r')
zip_ref.extractall(extract_to)
zip_ref.close()
if rm_zip_file_after_extraction:
path2file.unlink(missing_ok=True)
elif filename.endswith('.gz'):
import tarfile
file = tarfile.open(fileobj=response, mode="r|gz")
file.extractall(path=extract_to)
file.close()
elif filename.endswith('.pkl'):
# no need to extract it, but when you use the data make sure you torch.load it or pickle.load it.
print(f'about to test torch.load of: {path2file=}')
data = torch.load(path2file) # just to test
assert data is not None
print(f'{data=}')
pass
else:
raise ValueError(f'File type {filename=} not supported, edit code to support it.')
# path_2_zip_with_filename = path_2_ziplike / filename
# os.system(f'tar -xvzf {path_2_zip_with_filename} -C {path_2_dataset}/')
# if rm_zip_file:
# path_2_zip_with_filename.unlink(missing_ok=True)
# # raise ValueError(f'File type {filename=} not supported.')
print(f'done extracting: {path2file=}')
print(f'extracted at location: {path_used_for_dataset=}')
print(f'-->Succes downloading & extracting dataset at location: {path_used_for_dataset=}')
you can use my code with pip install ultimate-utils for the most up to date version.
In the other case, this warning showing up when the ml/dl model has different format.
For the example:
you want to open pickle, but the model format is .sav
Solution:
you need to change the format to original format
pickle --> .pkl
tensorflow --> .h5
etc.
In my case, the zip file itself was missing from that directory - thus when I tried to unzip it, I got the error "BadZipFile: File is not a zip file". It got resolved after I moved the .zip file to the directory. Please confirm that the file is indeed present in your directory before running the python script.
In my case, the zip file was corrupted. I was trying to download the zip file with urllib.request.urlretrieve but the file wouldn't completely download for some reason.
I connected to a VPN, the file downloaded just fine, and I was able to open the file.

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