IOError: [Errno 22] invalid mode ('w') or filename

Question

I am getting this error thrown when trying to make a file. It is being designed to take a created .csv file and put it into a plain text file.

I would like it to create a new file after it has been run with the date and time stamp but I seem to get the Errno 22 when trying to generate the file.

Any ideas?

import csv
import time

f = open(raw_input('Enter file name: '),"r")

saveFile = open ('Bursarcodes_'+time.strftime("%x")+ '_'+time.strftime("%X")+
                 '.txt', 'w+')

csv_f = csv.reader(f)

for row in csv_f:
    saveFile.write( 'insert into bursarcode_lookup(bursarcode, note_id)' +
                    ' values (\'' + row[0] + '\', ' + row[1] + ')\n')

f.close()

saveFile.close()

Answer 1

You cannot have slashes (/) and colons (:, but allowed in Unix) in your file name, but they are exactly what strftime generates in its output.

Python tries to help you, it says:

No such file or directory: 'Bursarcodes_01/09/15_19:59:24.txt'

Replace time.strftime("%x") with this:

time.strftime("%x").replace('/', '.')

...and time.strftime("%X") with this:

time.strftime("%X").replace(':', '_')

Answer 2

A cleaned-up and extended version:

import csv
import sys
import time

def make_output_fname():
    # Thanks to @Andrew:
    return time.strftime("Bursarcodes_%x_%X.txt").replace("/", "-").replace(":", "-")

def main(csv_fname=None, outfname=None, *args):
    if not csv_fname:
        # first arg not given - prompt for filename
        csv_fname = raw_input("Enter .csv file name: ")

    if not outfname:
        # second arg not given - use serialized filename
        outfname = make_output_fname()

    with open(csv_fname) as inf, open(outfname, "w") as outf:
        incsv = csv.reader(inf)
        for row in incsv:
            outf.write(
                "insert into bursarcode_lookup(bursarcode, note_id) values ('{0}', '{1}')\n"
                .format(*row)
            )

if __name__=="__main__":
    # pass any command-line arguments to main()
    main(*sys.argv[1:])

You can now run it from the command-line as well.

Note that if any data items in your csv file contain unescaped single-quotes (') you will get invalid sql.