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Using Argparse and Json Together

I am starting with Python.

I wanted to know if Argparse and JSON can be used together. Say I have variablesp,q,r

I could add them to argparse as -

parser.add_argument('-p','--param1',help='x variable', required=True)
parser.add_argument('-q','--param2',help='y variable', required=True)
parser.add_argument('-r','--param3',help='z variable', required=True)

Now suppose I wanted to read the same variables from a JSON file, can this be done? Therefore, I could enter values ​​either from the command line or from a JSON file.

JSON input file -

{
    "testOwner": "my name",
    "tests": [
        "test1",
        "test2",
        "test3"
    ],

    "testParameters": {
        "test1": {
            "param1": "0",
            "param2": "20",
            "param3" : "True"
        },

        "test2": {
            "param1": "cc"
        }
    }   
}
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2 answers

The namespace argsfrom parse_argscan be converted to a dictionary with:

argparse_dict = vars(args)

JSON values ​​are also in the dictionary, for example json_dict. You can copy selected values ​​from one dictionary to another or perform an update of the whole scale:

argparse_dict.update(json_dict)

, json_dict argparse.

, (), , . , nargs argparse.

parser :

In [292]: args=parser.parse_args('-p one -q two -r three'.split())
In [293]: args
Out[293]: Namespace(param1='one', param2='two', param3='three')
In [295]: args_dict = vars(args)    
In [296]: args_dict
Out[296]: {'param1': 'one', 'param2': 'two', 'param3': 'three'}

JSON (json.loads?) :

In [317]: json_dict
Out[317]: 
{'testOwner': 'my name',
 'testParameters': {'test1': {'param1': '0', 'param2': '20', 'param3': 'True'},
  'test2': {'param1': 'cc'}},
 'tests': ['test1', 'test2', 'test3']}

, Ipython, , JSON

argparse :

In [318]: json_dict['testParameters']['test3']=args_dict
In [319]: json_dict
Out[319]: 
{'testOwner': 'my name',
 'testParameters': {'test1': {'param1': '0', 'param2': '20', 'param3': 'True'},
  'test2': {'param1': 'cc'},
  'test3': {'param1': 'one', 'param2': 'two', 'param3': 'three'}},
 'tests': ['test1', 'test2', 'test3']}

3- test , ( conincidence) tests. json_dict['testParameters']['test2']=args_dict test2.

args undefined 'test2':

In [320]: args_dict1=args_dict.copy()    
In [322]: args_dict1.update(json_dict['testParameters']['test2'])
In [324]: json_dict['testParameters']['test2']=args_dict1
In [325]: json_dict
Out[325]: 
{'testOwner': 'my name',
 'testParameters': {'test1': {'param1': '0', 'param2': '20', 'param3': 'True'},
  'test2': {'param1': 'cc', 'param2': 'two', 'param3': 'three'},
  'test3': {'param1': 'one', 'param2': 'two', 'param3': 'three'}},
 'tests': ['test1', 'test2', 'test3']}

update, "cc" JSON.

+4

, JSON :

d = {"name": ["-x", "--xvar"], "help": "Help message", "required": True}

"" dict :

parser = argparse.ArgumentParser()
parser.add_argument(*(d.pop("name")), **d) 
# Put the 'name' as name/flag and then unpack the rest of
# the dict as the rest of the arguments
parser.parse_args("--xvar 12".split())
>>> Namespace(xvar='12')

dict add_arguments. / , , action, type, choices.

dict, , . / dict , dict:

d = {("-x", "--xvar"): {"help": "Help message for x", "required": True}, 
     ("-y", "--yvar"): {"help": "Help message for y", "required": True}}
for names, args in d.iteritems():
    parser.add_argument(*names, **args) # Use a similar unpacking 'magic' as the first example
parser.parse_args("-x 12 --yvar 42".split())
>>> Namespace(xvar='12', yvar='42')

OP, , , JSON.

d = {"-x": "12", "-y": "42"}
args = []
for item in d.items():
    args.extend(item)
parser.parse_args(args)
>>> Namespace(xvar='12', yvar='42')

2

argparse , , .

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