Port parameter checking to c++

Author: nyalldawson

python/core/processing/qgsprocessingalgorithm.sip

@@ -139,6 +139,17 @@ class QgsProcessingAlgorithm
  :rtype: bool
 %End
 
+    virtual bool checkParameterValues( const QVariantMap &parameters,
+                                       QgsProcessingContext &context, QString *message /Out/ = 0 ) const;
+%Docstring
+ Checks the supplied ``parameter`` values to verify that they satisfy the requirements
+ of this algorithm in the supplied ``context``. The ``message`` parameter will be
+ filled with explanatory text if validation fails.
+ Overridden implementations should also check this base class implementation.
+ :return: true if parameters are acceptable for the algorithm.
+ :rtype: bool
+%End
+
     QgsProcessingProvider *provider() const;
 %Docstring
  Returns the provider to which this algorithm belongs.

python/core/processing/qgsprocessingparameters.sip

@@ -168,6 +168,13 @@ class QgsProcessingParameterDefinition
  @see flags()
 %End
 
+    virtual bool checkValueIsAcceptable( const QVariant &input ) const;
+%Docstring
+ Checks whether the specified ``input`` value is acceptable for the
+ parameter. Returns true if the value can be accepted.
+ :rtype: bool
+%End
+
   protected:
 
 
@@ -356,7 +363,6 @@ class QgsProcessingParameterBoolean : QgsProcessingParameterDefinition
 %End
 
     virtual QString type() const;
-
 };
 
 class QgsProcessingParameterCrs : QgsProcessingParameterDefinition
@@ -421,7 +427,6 @@ class QgsProcessingParameterExtent : QgsProcessingParameterDefinition
 
     virtual QString type() const;
 
-
 };
 
 
@@ -444,6 +449,8 @@ class QgsProcessingParameterPoint : QgsProcessingParameterDefinition
 %End
 
     virtual QString type() const;
+    virtual bool checkValueIsAcceptable( const QVariant &input ) const;
+
 
 };
 
@@ -472,6 +479,8 @@ class QgsProcessingParameterFile : QgsProcessingParameterDefinition
 %End
 
     virtual QString type() const;
+    virtual bool checkValueIsAcceptable( const QVariant &input ) const;
+
 
     Behavior behavior() const;
 %Docstring
@@ -522,6 +531,8 @@ class QgsProcessingParameterMatrix : QgsProcessingParameterDefinition
 %End
 
     virtual QString type() const;
+    virtual bool checkValueIsAcceptable( const QVariant &input ) const;
+
 
     QStringList headers() const;
 %Docstring
@@ -590,6 +601,8 @@ class QgsProcessingParameterMultipleLayers : QgsProcessingParameterDefinition
 %End
 
     virtual QString type() const;
+    virtual bool checkValueIsAcceptable( const QVariant &input ) const;
+
 
     QgsProcessingParameterDefinition::LayerType layerType() const;
 %Docstring
@@ -602,6 +615,21 @@ class QgsProcessingParameterMultipleLayers : QgsProcessingParameterDefinition
 %Docstring
  Sets the layer ``type`` for layers acceptable by the parameter.
 .. seealso:: layerType()
+%End
+
+    int minimumNumberInputs() const;
+%Docstring
+ Returns the minimum number of layers required for the parameter. If the return value is < 1
+ then the parameter accepts any number of layers.
+.. seealso:: setMinimumNumberInputs()
+ :rtype: int
+%End
+
+    void setMinimumNumberInputs( int minimum );
+%Docstring
+ Sets the ``minimum`` number of layers required for the parameter. The minimum must be >= 1
+ if the parameter is not optional.
+.. seealso:: minimumNumberInputs()
 %End
 
 };
@@ -636,6 +664,8 @@ class QgsProcessingParameterNumber : QgsProcessingParameterDefinition
 %End
 
     virtual QString type() const;
+    virtual bool checkValueIsAcceptable( const QVariant &input ) const;
+
 
     double minimum() const;
 %Docstring
@@ -699,6 +729,8 @@ class QgsProcessingParameterRange : QgsProcessingParameterDefinition
 %End
 
     virtual QString type() const;
+    virtual bool checkValueIsAcceptable( const QVariant &input ) const;
+
 
     QgsProcessingParameterNumber::Type dataType() const;
 %Docstring
@@ -758,6 +790,8 @@ class QgsProcessingParameterEnum : QgsProcessingParameterDefinition
 %End
 
     virtual QString type() const;
+    virtual bool checkValueIsAcceptable( const QVariant &input ) const;
+
 
     QStringList options() const;
 %Docstring
@@ -911,6 +945,8 @@ class QgsProcessingParameterTableField : QgsProcessingParameterDefinition
 %End
 
     virtual QString type() const;
+    virtual bool checkValueIsAcceptable( const QVariant &input ) const;
+
 
     QString parentLayerParameter() const;
 %Docstring

python/plugins/processing/algs/gdal/GdalAlgorithmDialog.py

@@ -115,6 +115,6 @@ def parametersHaveChanged(self):
             commands = [c for c in commands if c not in ['cmd.exe', '/C ']]
             self.text.setPlainText(" ".join(commands))
         except AlgorithmDialogBase.InvalidParameterValue as e:
-            self.text.setPlainText(self.tr("Invalid value for parameter '{0}'").format(e.parameter.description))
+            self.text.setPlainText(self.tr("Invalid value for parameter '{0}'").format(e.parameter.description()))
         except:
             self.text.setPlainText("")

python/plugins/processing/algs/grass7/Grass7Algorithm.py

@@ -36,7 +36,8 @@
 from qgis.core import (QgsRasterLayer,
                        QgsApplication,
                        QgsProcessingUtils,
-                       QgsMessageLog)
+                       QgsMessageLog,
+                       QgsProcessingAlgorithm)
 from qgis.utils import iface
 
 from processing.core.GeoAlgorithm import GeoAlgorithm
@@ -578,9 +579,9 @@ def canExecute(self):
         message = Grass7Utils.checkGrass7IsInstalled()
         return not message, message
 
-    def checkParameterValuesBeforeExecuting(self):
+    def checkParameterValues(self, parameters, context):
         if self.module:
             if hasattr(self.module, 'checkParameterValuesBeforeExecuting'):
                 func = getattr(self.module, 'checkParameterValuesBeforeExecuting')
-                return func(self)
-        return
+                return func(self), None
+        return super(Grass7Algorithm, self).checkParameterValues(parameters, context)

python/plugins/processing/algs/qgis/FieldPyculator.py

@@ -184,6 +184,6 @@ def processAlgorithm(self, parameters, context, feedback):
 
         del writer
 
-    def checkParameterValuesBeforeExecuting(self):
+    def checkParameterValues(self, parameters, context):
         # TODO check that formula is correct and fields exist
-        pass
+        return super(FieldsPyculator, self).checkParameterValues(parameters, context)

python/plugins/processing/algs/qgis/FieldsCalculator.py

@@ -164,11 +164,12 @@ def processAlgorithm(self, parameters, context, feedback):
                 self.tr('An error occurred while evaluating the calculation '
                         'string:\n{0}').format(error))
 
-    def checkParameterValuesBeforeExecuting(self):
+    def checkParameterValues(self, parameters, context):
         newField = self.getParameterValue(self.NEW_FIELD)
         fieldName = self.getParameterValue(self.FIELD_NAME).strip()
         if newField and len(fieldName) == 0:
             return self.tr('Field name is not set. Please enter a field name')
+        return super(FieldsCalculator, self).checkParameterValues(parameters, context)
 
     def createCustomParametersWidget(self, parent):
         return FieldsCalculatorDialog(self)

python/plugins/processing/algs/qgis/ui/FieldsCalculatorDialog.py

@@ -209,8 +209,10 @@ def getParamValues(self):
         parameters['FORMULA'] = self.builder.expressionText()
         parameters['OUTPUT_LAYER'] = self.leOutputFile.text().strip() or None
 
-        msg = self.alg.checkParameterValuesBeforeExecuting()
-        if msg:
+        context = dataobjects.createContext()
+
+        ok, msg = self.alg.checkParameterValues(parameters, context)
+        if not ok:
             QMessageBox.warning(
                 self, self.tr('Unable to execute algorithm'), msg)
             return {}

python/plugins/processing/algs/saga/SagaAlgorithm.py

@@ -342,17 +342,16 @@ def exportRasterLayer(self, source):
         sessionExportedLayers[source] = destFilename
         return 'io_gdal 0 -TRANSFORM 1 -RESAMPLING 0 -GRIDS "' + destFilename + '" -FILES "' + source + '"'
 
-    def checkParameterValuesBeforeExecuting(self):
+    def checkParameterValues(self, parameters, context):
         """
         We check that there are no multiband layers, which are not
         supported by SAGA, and that raster layers have the same grid extent
         """
         extent = None
-        context = dataobjects.createContext()
-        for param in self.parameters:
+        for param in self.parameterDefinitions():
             files = []
             if isinstance(param, ParameterRaster):
-                files = [param.value]
+                files = [parameters[param.name()]]
             elif (isinstance(param, ParameterMultipleInput) and
                     param.datatype == dataobjects.TYPE_RASTER):
                 if param.value is not None:
@@ -362,12 +361,13 @@ def checkParameterValuesBeforeExecuting(self):
                 if layer is None:
                     continue
                 if layer.bandCount() > 1:
-                    return self.tr('Input layer {0} has more than one band.\n'
-                                   'Multiband layers are not supported by SAGA').format(layer.name())
+                    return False, self.tr('Input layer {0} has more than one band.\n'
+                                          'Multiband layers are not supported by SAGA').format(layer.name())
                 if not self.allowUnmatchingGridExtents:
                     if extent is None:
                         extent = (layer.extent(), layer.height(), layer.width())
                     else:
                         extent2 = (layer.extent(), layer.height(), layer.width())
                         if extent != extent2:
-                            return self.tr("Input layers do not have the same grid extent.")
+                            return False, self.tr("Input layers do not have the same grid extent.")
+        return super(SagaAlgorithm, self).checkParameterValues(parameters, context)

python/plugins/processing/core/GeoAlgorithm.py

@@ -90,18 +90,6 @@ def getCustomModelerParametersDialog(self, modelAlg, algName=None):
         """
         return None
 
-    def checkParameterValuesBeforeExecuting(self):
-        """If there is any check to do before launching the execution
-        of the algorithm, it should be done here.
-
-        If values are not correct, a message should be returned
-        explaining the problem.
-
-        This check is called from the parameters dialog, and also when
-        calling from the console.
-        """
-        return None
-
     def processBeforeAddingToModeler(self, alg, model):
         """Add here any task that has to be performed before adding an algorithm
         to a model, such as changing the value of a parameter depending on value
@@ -150,23 +138,6 @@ def execute(self, parameters, context=None, feedback=None, model=None):
             QgsMessageLog.logMessage('\n'.join(lines), self.tr('Processing'), QgsMessageLog.CRITICAL)
             raise GeoAlgorithmExecutionException(str(e) + self.tr('\nSee log for more details'), lines, e)
 
-    def _checkParameterValuesBeforeExecuting(self, context=None):
-        if context is None:
-            context = dataobjects.createContext()
-        for param in self.parameters:
-            if isinstance(param, (ParameterRaster, ParameterVector,
-                                  ParameterMultipleInput)):
-                if param.value:
-                    if isinstance(param, ParameterMultipleInput):
-                        inputlayers = param.value.split(';')
-                    else:
-                        inputlayers = [param.value]
-                    for inputlayer in inputlayers:
-                        obj = QgsProcessingUtils.mapLayerFromString(inputlayer, context)
-                        if obj is None:
-                            return "Wrong parameter value: " + param.value
-        return self.checkParameterValuesBeforeExecuting()
-
     def runPostExecutionScript(self, feedback):
         scriptFile = ProcessingConfig.getSetting(
             ProcessingConfig.POST_EXECUTION_SCRIPT)

python/plugins/processing/core/Processing.py

@@ -204,8 +204,8 @@ def runAlgorithm(algOrName, onFinish, *args, **kwargs):
         else:
             context = dataobjects.createContext()
 
-        msg = alg._checkParameterValuesBeforeExecuting(context)
-        if msg:
+        ok, msg = alg.checkParameterValues(parameters, context)
+        if not ok:
             # fix_print_with_import
             print('Unable to execute algorithm\n' + str(msg))
             QgsMessageLog.logMessage(Processing.tr('Unable to execute algorithm\n{0}').format(msg),

python/plugins/processing/gui/AlgorithmDialog.py

@@ -101,18 +101,15 @@ def getParamValues(self):
                 continue
             if not param.isDestination():
                 wrapper = self.mainWidget.wrappers[param.name()]
+                value = None
                 if wrapper.widget:
                     value = wrapper.value()
                     parameters[param.name()] = value
 
-                    #TODO
-                    #if not self.setParamValue(param, wrapper):
-                    #    raise AlgorithmDialogBase.InvalidParameterValue(param, wrapper.widget)
+                    if not param.checkValueIsAcceptable(value):
+                        raise AlgorithmDialogBase.InvalidParameterValue(param, wrapper.widget)
             else:
                 parameters[param.name()] = self.mainWidget.outputWidgets[param.name()].getValue()
-                # TODO
-                #if isinstance(output, (OutputRaster, OutputVector, OutputTable)):
-                #    output.open = self.mainWidget.checkBoxes[param.name()].isChecked()
 
         return parameters
 
@@ -127,12 +124,6 @@ def getLayersToOpen(self):
 
         return layer_outputs
 
-    def setParamValue(self, param, wrapper):
-        if wrapper.widget:
-            return param.setValue(wrapper.value())
-        else:
-            return True
-
     def checkExtentCRS(self):
         unmatchingCRS = False
         hasExtent = False
@@ -199,9 +190,7 @@ def accept(self):
                                              QMessageBox.No)
                 if reply == QMessageBox.No:
                     return
-            # TODO
-            #msg = self.alg._checkParameterValuesBeforeExecuting(context)
-            msg = None
+            ok, msg = self.alg.checkParameterValues(parameters, context)
             if msg:
                 QMessageBox.warning(
                     self, self.tr('Unable to execute algorithm'), msg)
@@ -258,7 +247,7 @@ def accept(self):
             except:
                 pass
             self.bar.clearWidgets()
-            self.bar.pushMessage("", self.tr("Wrong or missing parameter value: {0}").format(e.parameter.description),
+            self.bar.pushMessage("", self.tr("Wrong or missing parameter value: {0}").format(e.parameter.description()),
                                  level=QgsMessageBar.WARNING, duration=5)
 
     def finish(self, result, context):

python/plugins/processing/gui/AlgorithmDialogBase.py

@@ -222,9 +222,6 @@ def setText(self, text):
     def getParamValues(self):
         return {}
 
-    def setParamValue(self, param, widget, alg=None):
-        pass
-
     def accept(self):
         pass
 

python/plugins/processing/gui/BatchAlgorithmDialog.py

@@ -73,6 +73,8 @@ def accept(self):
         self.load = []
         self.canceled = False
 
+        context = dataobjects.createContext()
+
         for row in range(self.mainWidget.tblParameters.rowCount()):
             col = 0
             parameters = {}
@@ -81,9 +83,9 @@ def accept(self):
                     continue
                 wrapper = self.mainWidget.wrappers[row][col]
                 parameters[param.name()] = wrapper.value()
-                if not self.mainWidget.setParamValue(param, wrapper, alg):
+                if not param.checkValueIsAcceptable(wrapper.value(), context):
                     self.bar.pushMessage("", self.tr('Wrong or missing parameter value: {0} (row {1})').format(
-                                         param.description, row + 1),
+                                         param.description(), row + 1),
                                          level=QgsMessageBar.WARNING, duration=5)
                     self.algs = None
                     return
@@ -122,8 +124,6 @@ def accept(self):
         except:
             pass
 
-        context = dataobjects.createContext()
-
         for count, parameters in enumerate(self.alg_parameters):
             self.setText(self.tr('\nProcessing algorithm {0}/{1}...').format(count + 1, len(self.alg_parameters)))
             self.setInfo(self.tr('<b>Algorithm {0} starting...</b>').format(self.alg.displayName()))