python script command line arguments from file

Question

test.txt

port = 1234

host = abc.com

test.py

port = sys.argv[1]

host = sys.argv[2]

I want to provide test.txt as input to python script:

python test.py test.txt

so that , port and host values in text file should pass as command line arguments to python script which are inturn passed to port and host in the script.

if i do :

python test.py 1234 abc.com

the arguments are passed to sys.argv[1] and sys.argv[2]

the same i want to achieve using reading from txt file.

Thanks.

Answer 1

Given a test.txt file with a section header:

[settings]
port = 1234
host = abc.com

You could use the ConfigParser library to get the host and port content:

import sys
import ConfigParser

if __name__ == '__main__':
    config = ConfigParser.ConfigParser()
    config.read(sys.argv[1])
    print config['settings']['host']
    print config['settings']['port']

In Python 3 it's called configparser (lowercase).

Answer 2

I would instead just write the text file as:

1234
abc.com

Then you can do this:

input_file = open(sys.argv[1])
port = int(input_file.readLine())
host = input_file.readLine()

Answer 3

A way to do so in Linux is to do:

 awk '{print $3}' test.txt | xargs python test.py

Your .txt file can be separated in 3 columns, of which the 3rd contains the values for port and host. awk '{print $3}' extracts those column and xargs feeds them as input parameters to your python script.

Of course, that is only if you don't want to modify your .py script to read the file and extract those input values.