Nyall,
could we have defineCharacteristicsFromFile method in
QgsProcessingAlgorithm ?.
the diff with canExecute is more of a working draft.
On Thu, Mar 15, 2018 at 03:27:50PM +0100, Rashad Kanavath wrote:
> Hello,
>
> On Wed, Mar 14, 2018 at 4:38 AM, Nyall Dawson <nyall.daw...@gmail.com>
> wrote:
>
> > On 13 March 2018 at 20:56, Rashad Kanavath <rashad.kanav...@c-s.fr> wrote:
> > > if a provier is enabled then qgis reads all algorithm's during
> > > startup. This involves reading descriptor files and doing all parsing
> > > required to make gui when user actually open algorithm (click on
> > > treeitem).
> > > So If I have like three provider enabled it takes more time to start
> > qgis than
> > > usual. Even though, I might open one or two later at some point.
> > >
> > > It is not necessary here to parse "all" data during startup. name and
> > > group name is only needed to fill provider-algorithm tree. This is
> > > true for any provider which uses descriptor files (OTB, GRASS, SAGA
> > etc..).
> >
> > Actually it's a bit trickier here -- models make things more complex
> > as they self-validate on creation, and need full knowledge of the
> > dependent algorithm's parameters and outputs.
> >
>
> Yes. there are different cases like modeler, standard, batch, scripts.
> I tried to utilize canExecute() in otb and seems to be working.
> You already have a very flexible, strong API in qgis processing such
> trickier feature like this one has become too easy!!.
>
> I had to call alg.canExecute() in two places and that's it.
> diff attached below. With this loading time will be hopefully improved for
> OTB, SAGA, GRASS GIS.
>
> index f5bdc40dc5..1cca57769a 100644
> --- a/python/plugins/processing/modeler/ModelerParametersDialog.py
> +++ b/python/plugins/processing/modeler/ModelerParametersDialog.py
> @@ -70,6 +70,7 @@ class ModelerParametersDialog(QDialog):
> QDialog.__init__(self)
> self.setModal(True)
> # The algorithm to define in this dialog. It is an instance of
> QgsProcessingModelAlgorithm
> + alg.canExecute()
> self._alg = alg
> # The model this algorithm is going to be added to
> self.model = model
> @@ -80,6 +81,9 @@ class ModelerParametersDialog(QDialog):
> settings = QgsSettings()
> self.restoreGeometry(settings.value("/Processing/
> modelParametersDialogGeometry", QByteArray()))
>
> + def algorithm(self):
> + return self._alg
> +
> def closeEvent(self, event):
> settings = QgsSettings()
> settings.setValue("/Processing/modelParametersDialogGeometry",
> self.saveGeometry())
> @@ -242,7 +246,6 @@ class ModelerParametersDialog(QDialog):
> outTypes = []
> elif not isinstance(outTypes, (tuple, list)):
> outTypes = [outTypes]
> -
> return self.model.availableSourcesForChild(self.childId,
> [p.typeName() for p in paramType if
>
> issubclass(p, QgsProcessingParameterDefinition)],
> [o.typeName() for o in
> outTypes if
> diff --git a/src/core/processing/models/qgsprocessingmodelchildalgorithm.cpp
> b/src/core/processing/models/qgsprocessingmodelchildalgorithm.cpp
> index f5f8074c88..01906a7f62 100644
> --- a/src/core/processing/models/qgsprocessingmodelchildalgorithm.cpp
> +++ b/src/core/processing/models/qgsprocessingmodelchildalgorithm.cpp
> @@ -58,7 +58,7 @@ QgsProcessingModelChildAlgorithm &
> QgsProcessingModelChildAlgorithm::operator=( c
>
> const QgsProcessingAlgorithm *QgsProcessingModelChildAlgorithm::algorithm()
> const
> {
> - return mAlgorithm.get();
> + return mAlgorithm && mAlgorithm->canExecute() ? mAlgorithm.get():
> nullptr;
> }
>
> void QgsProcessingModelChildAlgorithm::setModelOutputs( const
> QMap<QString, QgsProcessingModelOutput> &modelOutputs )
>
> test code for otb provider:
> https://gitlab.orfeo-toolbox.org/orfeotoolbox/qgis-otb-plugin
> I can add modification to SAGA and GRASS if you are okay to move this to PR.
>
>
> > > Issue is more about calling defineDescriptorFile() in Algorithm's
> > > __init__ method. And ofcourse, one cannot avoid init when adding
> > > algorithm and tree need to add an instance of algorithm. what can be
> > > done?
> >
> > What I've been thinking/planning is to take advantage of task manager
> > here. So basically:
> >
> > - on processing startup, there's no providers added
> > - when the qgis interface is fully loaded then we fire up a background
> > task which loads the providers, allowing them to fully build their
> > available algorithms and parameters without blocking the startup
> > - after the task completes, the tree is populated
> >
>
> this is still loading all algorithm with parsing but things will be in
> background to not block ui for users. correct?
> In that case, you could include above diff and then add loading in
> background task. IMHO that will be best.
>
>
> > I'd like to see more plugins take this approach, so that qgis can load
> > nice and quick and the slow stuff happens without annoying users...
> >
> > Nyall
> > _______________________________________________
> > QGIS-Developer mailing list
> > QGIS-Developer@lists.osgeo.org
> > List info: https://lists.osgeo.org/mailman/listinfo/qgis-developer
> > Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-developer
> >
>
>
>
> --
> Regards,
> Rashad
--
Take care,
Rashad
_______________________________________________
QGIS-Developer mailing list
QGIS-Developer@lists.osgeo.org
List info: https://lists.osgeo.org/mailman/listinfo/qgis-developer
Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-developer
