Re: [PATCH v10 08/10] qcow2.py: Introduce '-j' key to dump in JSON format

[Andrey Shinkevich <andrey.shinkevich@virtuozzo.com>]

On 16.07.2020 17:38, Vladimir Sementsov-Ogievskiy wrote:
> 16.07.2020 17:36, Andrey Shinkevich wrote:
>> On 16.07.2020 13:20, Vladimir Sementsov-Ogievskiy wrote:
>>> 14.07.2020 00:36, Andrey Shinkevich wrote:
>>>> Add the command key to the qcow2.py arguments list to dump QCOW2
>>>> metadata in JSON format. Here is the suggested way to do that. The
>>>> implementation of the dump in JSON format is in the patch that 
>>>> follows.
>>>>
>>>> Signed-off-by: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com>
>>>> ---
>>>>   tests/qemu-iotests/qcow2.py        | 19 +++++++++++++++----
>>>>   tests/qemu-iotests/qcow2_format.py | 16 ++++++++--------
>>>>   2 files changed, 23 insertions(+), 12 deletions(-)
>>>>
>>>> diff --git a/tests/qemu-iotests/qcow2.py b/tests/qemu-iotests/qcow2.py
>>>> index 0910e6a..7402279 100755
>> ...
>>>> @@ -134,6 +137,11 @@ cmds = [
>>>>       def main(filename, cmd, args):
>>>> +    global dump_json
>>>> +    dump_json = '-j' in sys.argv
>>>> +    if dump_json:
>>>> +        sys.argv.remove('-j')
>>>> +        args.remove('-j')
>>>
>>> I'd prefer to access sys.argv in one place (in "if __name__ ...").
>>>
>>
>> In case we move the block
>>
>>      global dump_json
>>      dump_json = '-j' in sys.argv
>>
>>          if dump_json:
>>              sys.argv.remove('-j')
>>
>> from main() to the body of "if __name__ == '__main__'"
>>
>> we get the following error -
>>
>> "SyntaxError: name 'dump_json' is assigned to before global declaration"
>
> you don't need "global" declaration outside of a function
>
>

OK, thanks. However, if we want to parse more keys in future, will we do 
all that parsing in the body of "if __name__ == '__main__'"?


Andrey