[Qgis-developer] [QGIS-Processing] Define optional parameters in Script

[Victor Olaya]

I replied in the PR in gitHub ;-)

2015-10-23 18:17 GMT+02:00 René-Luc Dhont <rldhont at gmail.com>:
> Hi victor,
>
> Because codes are sometimes better than text, I made a pull-request to
> propose optional parameters in script and model.
> https://github.com/qgis/QGIS/pull/2396
>
> In my code, all parameters can be optional or not required and didn't modify
> the parameters value setter.
>
> I don't know if optional number, string or extent has to be None or default
> value if it is not set by the user.
>
> Reviews are welcome
>
> Regards,
> René-Luc
>
>
> Le 11/09/2015 13:44, Victor Olaya a écrit :
>>
>> Aside from the syntax...I am not sure it is a good idea...
>>
>> I mean, it is a good idea to allow optional parameters...but that is a
>> big change in the current semantics of Processing algorithms. Some
>> params can be optional (layers, tables), and have a setting for that.
>> When they are not used, their value is None, but the value has to be
>> passed (so an optional layer param is a layer param that can be None).
>> Allowing optional parameters would require some importante changes in
>> many places in Processing, specially in the modeler, so i would
>> suggest some more discussion about this.
>>
>> Not sure if that can maybe be added to the WPS plugin part, so nothing
>> changes in Processing, but the WPS service exposes the parameters as
>> optional and then fills the values with a default one before actually
>> callin gprocessing.
>>
>> Hope this helps
>>
>> 2015-09-11 11:28 GMT+02:00 kimaidou <kimaidou at gmail.com>:
>>>
>>> Hi
>>>
>>> I would personaly use the second : add a new property for each input. If
>>> not
>>> given, this means the input is mandatory, if "opt" is present, make it
>>> optionnal.
>>>
>>> Cheers,
>>> Michael
>>>
>>> 2015-08-28 14:53 GMT+02:00 René-Luc Dhont <rldhont at gmail.com>:
>>>>
>>>> Hi Victor,
>>>>
>>>> I'm working on porting QGIS Processing to Web Processing Service, and I
>>>> have found that all parameters in a QGIS Processing script are
>>>> mandatory.
>>>> It would be useful to power define some parameters as optional.
>>>>
>>>> I think that I can propose some code but I'd like to know what is your
>>>> preferred way of defining optional parameters :
>>>> * an header line started by 'optional' with a list of parameter name
>>>> separated by comma
>>>> ##optional=SEGMENTS,DISTANCE
>>>> * an extra value at the end of the header line
>>>> ##SEGMENTS=number 5 opt
>>>>
>>>> Thanks
>>>> _______________________________________________
>>>> Qgis-developer mailing list
>>>> Qgis-developer at lists.osgeo.org
>>>> http://lists.osgeo.org/mailman/listinfo/qgis-developer
>>>
>>>
>>>
>>> _______________________________________________
>>> Qgis-developer mailing list
>>> Qgis-developer at lists.osgeo.org
>>> http://lists.osgeo.org/mailman/listinfo/qgis-developer
>
>