I want to create a script like this
./myscript.py -g parser -a parserapp
and whenever the script is missing one option such as ./myscript.py -g parser, it will print out usage and exit the script
The script should be: ./myscript.py -g parser -a parserapp
So, my question is how can I check if option -a or-g is missing; so, it can print out the usage for the script and exit.
Thank you for your help
Use argparse
import argparse
parser = argparse.ArgumentParser()
parser.add_argument("-g", "--gggg", help="g parameter",required=True)
parser.add_argument("-a", "--aaaa", help="a parameter",required=True)
args = parser.parse_args()
print args.g, args.a
When you run it with -h it will show help:
~#:python myscript.py -h
usage: myscript.py [-h] -g GGGG -a AAAA
optional arguments:
-h, --help show this help message and exit
-g GGGG, --gggg GGGG g parameter
-a AAAA, --aaaa AAAA a parameter
If you miss a parameter it will print error:
myscript.py: error: argument -g/--gggg is required
Parsing of parameters can be done with optparse or argparse. You can make nifty help options and so on. It's also easy to make different kinds of parameters to be accepted.
Use argparse: https://docs.python.org/2/howto/argparse.html
For your need argparse can check wether an argument is missing or not like this :
import argparse
parser = argparse.ArgumentParser(description='My Super Script')
parser.add_argument(
'--parser', '-p',
required=True,
help='Parser Type'
)
parser.add_argument(
'--application', '-a',
required=True,
help='Application Name'
)
args = parser.parse_args()
By default argparse will consider a named argument optional unless you specify required=True
If the two args are not provided this will print a default help.
ref
You can use argparse module.
For Python3.x, you can look here.
For Python2.x, you can look here.
Apart from argparse, you can also use getopt module.
Use getopt:
https://docs.python.org/3.1/library/getopt.html(Python3.x)
https://docs.python.org/2/library/getopt.html(Python2.x)
argparse