How to parse multiple nested sub-commands using python argparse?

Question

I am implementing a command line program which has interface like this:

cmd [GLOBAL_OPTIONS] {command [COMMAND_OPTS]} [{command [COMMAND_OPTS]} ...]
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Answer 1

You can always split up the command-line yourself (split sys.argv on your command names), and then only pass the portion corresponding to the particular command to parse_args -- You can even use the same Namespace using the namespace keyword if you want.

Grouping the commandline is easy with itertools.groupby:

import sys
import itertools
import argparse    

mycommands=['cmd1','cmd2','cmd3']

def groupargs(arg,currentarg=[None]):
    if(arg in mycommands):currentarg[0]=arg
    return currentarg[0]

commandlines=[list(args) for cmd,args in intertools.groupby(sys.argv,groupargs)]

#setup parser here...
parser=argparse.ArgumentParser()
#...

namespace=argparse.Namespace()
for cmdline in commandlines:
    parser.parse_args(cmdline,namespace=namespace)

#Now do something with namespace...

untested