Flask handle uploaded csv on the fly by csv module

Question

Simply, I need to work with files uploaded without saving it on server

working in cli script using open() every thing is fine,

using flask with file sent from data by ajax request neither open() function nor stream.read() method helped to work with the csv

open throws an exception itself

csv_f = open(request.files['csvfile'].stream, 'rb')

TypeError: expected str, bytes or os.PathLike object, not SpooledTemporaryFile

using .read() I can print it

csv_f = request.files['csvfile'].stream.read()
data = csv.reader(csv_f, delimiter = ',')

print(csv_f)

b'...'

but Iterating also throws exception

for row in data:

_csv.Error: iterator should return strings, not int (did you open the file in text mode?)

where do you fetch your file from (S3 bucket, hadoop, remote server...) ? — dallonsi, Mar 16 '21 at 13:34
Does this answer your question? [Python - writing and reading from a temporary file](https://stackoverflow.com/questions/39983886/python-writing-and-reading-from-a-temporary-file) — dallonsi, Mar 16 '21 at 13:40
`TypeError: expected str, bytes or os.PathLike object, not SpooledTemporaryFile` — Abd-Elaziz Sharaf, Mar 16 '21 at 13:53

Abd-Elaziz Sharaf · Accepted Answer · 2021-04-17T21:25:56.087

1

I found out the problem

the file is going throw request as a binary stream not a normal text

that's why it has a read method but unuseful when itrating

I had to use .decode() like this

request.files['csvfile'].stream.read().decode("utf-8")

instead of this request.files['csvfile'].stream.read()

edited Apr 17 '21 at 21:25

answered Mar 16 '21 at 15:54

Abd-Elaziz Sharaf

1 Answers1