Python argparse: Difference between revisions
From wikinotes
No edit summary |
|||
Line 1: | Line 1: | ||
Argparse is a builting python library for building commandline interfaces. | Argparse is a builting python library for building commandline interfaces. | ||
<syntaxhighlight lang="python"> | <syntaxhighlight lang="python"> | ||
import argparse | import argparse | ||
parser = argparse.ArgumentParser(description='Does thing real well') | parser = argparse.ArgumentParser(description='Does thing real well') | ||
parser.add_argument('-v', '--verbose', | parser.add_argument('-v', '--verbose', | ||
action='store_true', help='enable verbose logging') | action='store_true', help='enable verbose logging') | ||
args = parser.parse_args() | args = parser.parse_args() | ||
print(args.verbose) # True | print(args.verbose) # True | ||
</syntaxhighlight> | </syntaxhighlight> | ||
= | = Arguments = | ||
<blockquote> | |||
== Argument Types == | |||
<blockquote> | <blockquote> | ||
<syntaxhighlight lang="python"> | <syntaxhighlight lang="python"> | ||
# number of args | # number of args | ||
Line 33: | Line 29: | ||
</syntaxhighlight> | </syntaxhighlight> | ||
Samples: | |||
<syntaxhighlight lang="python"> | <syntaxhighlight lang="python"> | ||
# | # foo my/output/file | ||
parser.add_argument('output-file', | parser.add_argument('output-file', | ||
help='filepath to save spreadsheet to') | help='filepath to save spreadsheet to') | ||
# | # foo -s today | ||
parser.add_argument('-s', '--start-date', | parser.add_argument('-s', '--start-date', | ||
nargs=1, help='date to start from') | nargs=1, help='date to start from') | ||
# | # foo -v | ||
parser.add_argument('-v', '--verbose', | parser.add_argument('-v', '--verbose', | ||
action='store_true', help='verbose logging') | action='store_true', help='verbose logging') | ||
</syntaxhighlight> | </syntaxhighlight> | ||
</blockquote><!-- | </blockquote><!-- Argument Types --> | ||
</blockquote><!-- Arguments --> | |||
= | = Parsers = | ||
<blockquote> | <blockquote> | ||
== SubParsers == | |||
= | |||
<blockquote> | <blockquote> | ||
Subparsers let you bind a different parser to sub-commands.<br> | |||
(ex. <code>git checkout ${params}</code> vs <code>git fetch ${params}</code>) | |||
< | |||
</ | |||
< | |||
<syntaxhighlight lang="bash"> | |||
# create parser | |||
git_parser = argparse.ArgumentParser() | |||
# create subparsers | |||
subparsers = git_parser.add_subparsers(dest="git_subparser") | |||
git_checkout_parser = subparsers.add_parser("checkout") | |||
git_fetch_parser = subparser.add_parser("fetch") | |||
git_fetch_parser = subparser.add_parser("show") | |||
# | # add arguments to subparsers | ||
git_checkout_parser.add_argument("file_or_commit", help="file/commit to checkout") | |||
# identifying subparser, and parsing args | |||
args = git_parser.parse_args() | |||
if args.git_subparser == "checkout": | |||
# ... | |||
elif args.git_subparser == "fetch": | |||
# ... | |||
elif args.git_subparser == "show": | |||
# ... | |||
</syntaxhighlight> | </syntaxhighlight> | ||
</blockquote><!-- SubParsers --> | </blockquote><!-- SubParsers --> | ||
</blockquote><!-- Parsers --> |
Revision as of 15:47, 9 April 2022
Argparse is a builting python library for building commandline interfaces.
import argparse
parser = argparse.ArgumentParser(description='Does thing real well')
parser.add_argument('-v', '--verbose',
action='store_true', help='enable verbose logging')
args = parser.parse_args()
print(args.verbose) # True
Arguments
Argument Types
# number of args (nothing) # positional nargs=1 # flag with N args nargs='+' # flag with one or more args (args.arg = []) nargs='?' # flag with one or no args (args.arg = None, 'var') #(set const=val to know when flag issued with no arguments) nargs='*' # flag with multiple or no args (args.arg = None, [], ['a','b',...]) # boolean args action='store_true' action='store_false'Samples:
# foo my/output/file parser.add_argument('output-file', help='filepath to save spreadsheet to') # foo -s today parser.add_argument('-s', '--start-date', nargs=1, help='date to start from') # foo -v parser.add_argument('-v', '--verbose', action='store_true', help='verbose logging')
Parsers
SubParsers
Subparsers let you bind a different parser to sub-commands.
(ex.git checkout ${params}
vsgit fetch ${params}
)# create parser git_parser = argparse.ArgumentParser() # create subparsers subparsers = git_parser.add_subparsers(dest="git_subparser") git_checkout_parser = subparsers.add_parser("checkout") git_fetch_parser = subparser.add_parser("fetch") git_fetch_parser = subparser.add_parser("show") # add arguments to subparsers git_checkout_parser.add_argument("file_or_commit", help="file/commit to checkout") # identifying subparser, and parsing args args = git_parser.parse_args() if args.git_subparser == "checkout": # ... elif args.git_subparser == "fetch": # ... elif args.git_subparser == "show": # ...