Add a processing parameter registry

to manage parameter metadata in a single place.
qgis · Mar 1, 2018 · eba96fb · eba96fb
1 parent 8b78440
commit eba96fb
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Showing 4 changed files with 174 additions and 104 deletions.
diff --git a/python/plugins/processing/core/Processing.py b/python/plugins/processing/core/Processing.py
@@ -45,6 +45,8 @@
                        QgsProcessingOutputMapLayer,
                        QgsProcessingOutputMultipleLayers)
 
+from .parameters import initializeParameters
+
 import processing
 from processing.core.ProcessingConfig import ProcessingConfig
 from processing.gui.MessageBarProgress import MessageBarProgress
@@ -67,6 +69,7 @@
 
 class Processing(object):
     BASIC_PROVIDERS = []
+    REGISTERED_PARAMETERS = dict()
 
     @staticmethod
     def activateProvider(providerOrName, activate=True):
@@ -97,6 +100,7 @@ def initialize():
             if QgsApplication.processingRegistry().addProvider(p):
                 Processing.BASIC_PROVIDERS.append(p)
         # And initialize
+        initializeParameters()
         ProcessingConfig.initialize()
         ProcessingConfig.readSettings()
         RenderingStyles.loadStyles()
@@ -107,6 +111,33 @@ def deinitialize():
             QgsApplication.processingRegistry().removeProvider(p)
 
         Processing.BASIC_PROVIDERS = []
+        Processing.REGISTERED_PARAMETERS = dict()
+
+    @staticmethod
+    def registerParameter(id, name, parameter, metadata=dict(), description=None):
+        """Register a new parameter.
+        The ``name`` is a human readable translated string, the ``parameter`` is a class type with the base class ``qgis.core.QgsProcessingParameterDefinition``,
+        the ``metadata`` is a dictionary with additional metadata, mainly used for widget wrappers.
+        """
+        Processing.REGISTERED_PARAMETERS[id] = {
+            'name': name,
+            'parameter': parameter,
+            'metadata': metadata,
+            'description': description
+        }
+
+    @staticmethod
+    def unregisterParameter(name):
+        """Unregister a registered parameter with the given name.
+        """
+        del Processing.REGISTERED_PARAMETERS[name]
+
+    @staticmethod
+    def registeredParameters():
+        """Returns a set of registered parameters.
+        Each entry is a tuple consisting of a human readable name and the class.
+        """
+        return Processing.REGISTERED_PARAMETERS
 
     @staticmethod
     def runAlgorithm(algOrName, parameters, onFinish=None, feedback=None, context=None):

diff --git a/python/plugins/processing/core/parameters.py b/python/plugins/processing/core/parameters.py
@@ -41,12 +41,14 @@
                        QgsProcessingParameterDefinition,
                        QgsProcessingParameterRasterLayer,
                        QgsProcessingParameterVectorLayer,
+                       QgsProcessingParameterBand,
                        QgsProcessingParameterBoolean,
                        QgsProcessingParameterCrs,
                        QgsProcessingParameterRange,
                        QgsProcessingParameterPoint,
                        QgsProcessingParameterEnum,
                        QgsProcessingParameterExtent,
+                       QgsProcessingParameterExpression,
                        QgsProcessingParameterMatrix,
                        QgsProcessingParameterFile,
                        QgsProcessingParameterField,
@@ -55,10 +57,36 @@
                        QgsProcessingParameterFolderDestination,
                        QgsProcessingParameterRasterDestination,
                        QgsProcessingParameterString,
+                       QgsProcessingParameterMapLayer,
                        QgsProcessingParameterMultipleLayers,
                        QgsProcessingParameterFeatureSource,
                        QgsProcessingParameterNumber)
 
+from PyQt5.QtCore import QCoreApplication
+
+PARAMETER_NUMBER = 'Number'
+PARAMETER_RASTER = 'Raster Layer'
+PARAMETER_TABLE = 'Vector Layer'
+PARAMETER_VECTOR = 'Vector Features'
+PARAMETER_STRING = 'String'
+PARAMETER_EXPRESSION = 'Expression'
+PARAMETER_BOOLEAN = 'Boolean'
+PARAMETER_TABLE_FIELD = 'Vector Field'
+PARAMETER_EXTENT = 'Extent'
+PARAMETER_FILE = 'File'
+PARAMETER_POINT = 'Point'
+PARAMETER_CRS = 'CRS'
+PARAMETER_MULTIPLE = 'Multiple Input'
+PARAMETER_BAND = 'Raster Band'
+PARAMETER_MAP_LAYER = 'Map Layer'
+PARAMETER_RANGE = 'Range'
+PARAMETER_ENUM = 'Enum'
+PARAMETER_MATRIX = 'Matrix'
+PARAMETER_VECTOR_DESTINATION = 'Vector Destination'
+PARAMETER_FILE_DESTINATION = 'File Destination'
+PARAMETER_FOLDER_DESTINATION = 'Folder Destination'
+PARAMETER_RASTER_DESTINATION = 'Raster Destination'
+
 
 def getParameterFromString(s):
     # Try the parameter definitions used in description files
@@ -209,3 +237,53 @@ def getParameterFromString(s):
         param = QgsProcessingParameters.parameterFromScriptCode(s)
         if param:
             return param
+
+
+def initializeParameters():
+    from processing.core.Processing import Processing
+
+    """
+    ModelerParameterDefinitionDialog.PARAMETER_TABLE: QCoreApplication.translate('Processing',
+                                                                                 'A vector layer parameter, e.g. for algorithms which change layer styles, edit layers in place, or other operations which affect an entire layer.'),
+    """
+
+    Processing.registerParameter(PARAMETER_MAP_LAYER, QCoreApplication.translate('Processing', 'Map Layer'),
+                                 QgsProcessingParameterMapLayer,
+                                 description=QCoreApplication.translate('Processing', 'A generic map layer parameter, which accepts either vector or raster layers.'))
+    Processing.registerParameter(PARAMETER_BAND, QCoreApplication.translate('Processing', 'Raster Band'),
+                                 QgsProcessingParameterBand,
+                                 description=QCoreApplication.translate('Processing', 'A raster band parameter, for selecting an existing band from a raster source.'))
+    Processing.registerParameter(PARAMETER_EXPRESSION, QCoreApplication.translate('Processing', 'Expression'),
+                                 QgsProcessingParameterExpression,
+                                 description=QCoreApplication.translate('Processing', 'A QGIS expression parameter, which presents an expression builder widget to users.'))
+    Processing.registerParameter(PARAMETER_RASTER, QCoreApplication.translate('Processing', 'Raster Layer'), QgsProcessingParameterRasterLayer,
+                                 description=QCoreApplication.translate('Processing', 'A raster layer parameter.'))
+    Processing.registerParameter(PARAMETER_TABLE, QCoreApplication.translate('Processing', 'Vector Layer'), QgsProcessingParameterVectorLayer,
+                                 description=QCoreApplication.translate('Processing', 'A vector feature parameter, e.g. for algorithms which operate on the features within a layer.'))
+    Processing.registerParameter(PARAMETER_BOOLEAN, QCoreApplication.translate('Processing', 'Boolean'), QgsProcessingParameterBoolean,
+                                 description=QCoreApplication.translate('Processing', 'A boolean parameter, for true/false values.'))
+    Processing.registerParameter(PARAMETER_CRS, QCoreApplication.translate('Processing', 'CRS'), QgsProcessingParameterCrs,
+                                 description=QCoreApplication.translate('Processing', 'A coordinate reference system (CRS) input parameter.'))
+    Processing.registerParameter(PARAMETER_RANGE, QCoreApplication.translate('Processing', 'Range'), QgsProcessingParameterRange)
+    Processing.registerParameter(PARAMETER_POINT, QCoreApplication.translate('Processing', 'Point'), QgsProcessingParameterPoint,
+                                 description=QCoreApplication.translate('Processing', 'A geographic point parameter.'))
+    Processing.registerParameter(PARAMETER_ENUM, QCoreApplication.translate('Processing', 'Enum'), QgsProcessingParameterEnum)
+    Processing.registerParameter(PARAMETER_EXTENT, QCoreApplication.translate('Processing', 'Extent'), QgsProcessingParameterExtent,
+                                 description=QCoreApplication.translate('Processing', 'A map extent parameter.'))
+    Processing.registerParameter(PARAMETER_MATRIX, QCoreApplication.translate('Processing', 'Matrix'), QgsProcessingParameterMatrix)
+    Processing.registerParameter(PARAMETER_FILE, QCoreApplication.translate('Processing', 'File'), QgsProcessingParameterFile,
+                                 description=QCoreApplication.translate('Processing', 'A file parameter, for use with non-map layer file sources.'))
+    Processing.registerParameter(PARAMETER_TABLE_FIELD, QCoreApplication.translate('Processing', 'Field'), QgsProcessingParameterField,
+                                 description=QCoreApplication.translate('Processing', 'A vector field parameter, for selecting an existing field from a vector source.'))
+    Processing.registerParameter(PARAMETER_VECTOR_DESTINATION, QCoreApplication.translate('Processing', 'Vector Destination'), QgsProcessingParameterVectorDestination)
+    Processing.registerParameter(PARAMETER_FILE_DESTINATION, QCoreApplication.translate('Processing', 'File Destination'), QgsProcessingParameterFileDestination)
+    Processing.registerParameter(PARAMETER_FOLDER_DESTINATION, QCoreApplication.translate('Processing', 'Folder Destination'), QgsProcessingParameterFolderDestination)
+    Processing.registerParameter(PARAMETER_RASTER_DESTINATION, QCoreApplication.translate('Processing', 'Raster Destination'), QgsProcessingParameterRasterDestination)
+    Processing.registerParameter(PARAMETER_STRING, QCoreApplication.translate('Processing', 'String'), QgsProcessingParameterString,
+                                 description=QCoreApplication.translate('Processing', 'A freeform string parameter.'))
+    Processing.registerParameter(PARAMETER_MULTIPLE, QCoreApplication.translate('Processing', 'Multiple Layers'), QgsProcessingParameterMultipleLayers,
+                                 description=QCoreApplication.translate('Processing', 'An input allowing selection of multiple sources, including multiple map layers or file sources.'))
+    Processing.registerParameter(PARAMETER_VECTOR, QCoreApplication.translate('Processing', 'Feature Source'), QgsProcessingParameterFeatureSource)
+    Processing.registerParameter(PARAMETER_NUMBER, QCoreApplication.translate('Processing', 'Number'), QgsProcessingParameterNumber,
+                                 description=QCoreApplication.translate('Processing', 'A numeric parameter, including float or integer values.'))
+    Processing.registeredParameters()
diff --git a/python/plugins/processing/modeler/ModelerDialog.py b/python/plugins/processing/modeler/ModelerDialog.py
@@ -154,12 +154,14 @@ def _dragEnterEvent(event):
                 event.ignore()
 
         def _dropEvent(event):
+            from processing.core.Processing import Processing
+
             if event.mimeData().hasText():
-                text = event.mimeData().text()
-                if text in ModelerParameterDefinitionDialog.paramTypes:
-                    self.addInputOfType(text, event.pos())
+                itemId = event.mimeData().text()
+                if itemId in Processing.registeredParameters():
+                    self.addInputOfType(itemId, event.pos())
                 else:
-                    alg = QgsApplication.processingRegistry().createAlgorithmById(text)
+                    alg = QgsApplication.processingRegistry().createAlgorithmById(itemId)
                     if alg is not None:
                         self._addAlgorithm(alg, event.pos())
                 event.accept()
@@ -545,25 +547,24 @@ def repaintModel(self, controls=True):
 
     def addInput(self):
         item = self.inputsTree.currentItem()
-        paramType = str(item.text(0))
-        self.addInputOfType(paramType)
+        param = item.data(0, Qt.UserRole)
+        self.addInputOfType(param)
 
     def addInputOfType(self, paramType, pos=None):
-        if paramType in ModelerParameterDefinitionDialog.paramTypes:
-            dlg = ModelerParameterDefinitionDialog(self.model, paramType)
-            dlg.exec_()
-            if dlg.param is not None:
-                if pos is None:
-                    pos = self.getPositionForParameterItem()
-                if isinstance(pos, QPoint):
-                    pos = QPointF(pos)
-                component = QgsProcessingModelParameter(dlg.param.name())
-                component.setDescription(dlg.param.name())
-                component.setPosition(pos)
-                self.model.addModelParameter(dlg.param, component)
-                self.repaintModel()
-                # self.view.ensureVisible(self.scene.getLastParameterItem())
-                self.hasChanged = True
+        dlg = ModelerParameterDefinitionDialog(self.model, paramType)
+        dlg.exec_()
+        if dlg.param is not None:
+            if pos is None:
+                pos = self.getPositionForParameterItem()
+            if isinstance(pos, QPoint):
+                pos = QPointF(pos)
+            component = QgsProcessingModelParameter(dlg.param.name())
+            component.setDescription(dlg.param.name())
+            component.setPosition(pos)
+            self.model.addModelParameter(dlg.param, component)
+            self.repaintModel()
+            # self.view.ensureVisible(self.scene.getLastParameterItem())
+            self.hasChanged = True
 
     def getPositionForParameterItem(self):
         MARGIN = 20
@@ -620,15 +621,19 @@ def _filterItem(self, item, text):
             return False
 
     def fillInputsTree(self):
+        from processing.core.Processing import Processing
+
         icon = QIcon(os.path.join(pluginPath, 'images', 'input.svg'))
         parametersItem = QTreeWidgetItem()
         parametersItem.setText(0, self.tr('Parameters'))
-        for paramType in sorted(ModelerParameterDefinitionDialog.paramTypes):
+        sortedParams = sorted(Processing.registeredParameters().items())
+        for param in sortedParams:
             paramItem = QTreeWidgetItem()
-            paramItem.setText(0, paramType)
+            paramItem.setText(0, param[0])
+            paramItem.setData(0, Qt.UserRole, param[1]['parameter'])
             paramItem.setIcon(0, icon)
             paramItem.setFlags(Qt.ItemIsEnabled | Qt.ItemIsSelectable | Qt.ItemIsDragEnabled)
-            paramItem.setToolTip(0, ModelerParameterDefinitionDialog.inputTooltip(paramType))
+            paramItem.setToolTip(0, param[1]['description'])
             parametersItem.addChild(paramItem)
         self.inputsTree.addTopLevelItem(parametersItem)
         parametersItem.setExpanded(True)