[processing][gdal] Better error messages when invalid parameters are passed

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

@@ -29,7 +29,8 @@ import os
 
 from qgis.PyQt.QtGui import QIcon
 
-from qgis.core import (QgsProcessingParameterRasterLayer,
+from qgis.core import (QgsProcessingException,
+                       QgsProcessingParameterRasterLayer,
                        QgsProcessingParameterCrs,
                        QgsProcessingOutputRasterLayer)
 from processing.algs.gdal.GdalAlgorithm import GdalAlgorithm
@@ -78,6 +79,9 @@ class AssignProjection(GdalAlgorithm):
 
     def getConsoleCommands(self, parameters, context, feedback, executing=True):
         inLayer = self.parameterAsRasterLayer(parameters, self.INPUT, context)
+        if inLayer is None:
+            raise QgsProcessingException(self.invalidRasterError(parameters, self.INPUT))
+
         fileName = inLayer.source()
 
         crs = self.parameterAsCrs(parameters, self.CRS, context).authid()

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

@@ -30,6 +30,7 @@ import os
 from qgis.PyQt.QtGui import QIcon
 
 from qgis.core import (QgsRasterFileWriter,
+                       QgsProcessingException,
                        QgsProcessingParameterDefinition,
                        QgsProcessingParameterRasterLayer,
                        QgsProcessingParameterEnum,
@@ -110,6 +111,9 @@ class ClipRasterByExtent(GdalAlgorithm):
 
     def getConsoleCommands(self, parameters, context, feedback, executing=True):
         inLayer = self.parameterAsRasterLayer(parameters, self.INPUT, context)
+        if inLayer is None:
+            raise QgsProcessingException('Invalid input layer {}'.format(parameters[self.INPUT] if self.INPUT in parameters else 'INPUT'))
+
         bbox = self.parameterAsExtent(parameters, self.EXTENT, context, inLayer.crs())
         if self.NODATA in parameters and parameters[self.NODATA] is not None:
             nodata = self.parameterAsDouble(parameters, self.NODATA, context)

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

@@ -31,6 +31,7 @@ from qgis.PyQt.QtGui import QIcon
 
 from qgis.core import (QgsRasterFileWriter,
                        QgsProcessing,
+                       QgsProcessingException,
                        QgsProcessingParameterDefinition,
                        QgsProcessingParameterFeatureSource,
                        QgsProcessingParameterRasterLayer,
@@ -124,6 +125,8 @@ class ClipRasterByMask(GdalAlgorithm):
 
     def getConsoleCommands(self, parameters, context, feedback, executing=True):
         inLayer = self.parameterAsRasterLayer(parameters, self.INPUT, context)
+        if inLayer is None:
+            raise QgsProcessingException(self.invalidRasterError(parameters, self.INPUT))
 
         maskLayer, maskLayerName = self.getOgrCompatibleSource(self.MASK, parameters, context, feedback, executing)
 

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

@@ -27,6 +27,7 @@ __revision__ = '$Format:%H$'
 
 import os
 from qgis.core import (QgsRasterFileWriter,
+                       QgsProcessingException,
                        QgsProcessingParameterDefinition,
                        QgsProcessingParameterRasterLayer,
                        QgsProcessingParameterBand,
@@ -102,6 +103,9 @@ class ColorRelief(GdalAlgorithm):
     def getConsoleCommands(self, parameters, context, feedback, executing=True):
         arguments = ['color-relief']
         inLayer = self.parameterAsRasterLayer(parameters, self.INPUT, context)
+        if inLayer is None:
+            raise QgsProcessingException(self.invalidRasterError(parameters, self.INPUT))
+
         arguments.append(inLayer.source())
         arguments.append(self.parameterAsFile(parameters, self.COLOR_TABLE, context))
 

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

@@ -25,7 +25,8 @@ __copyright__ = '(C) 2012, Victor Olaya'
 
 __revision__ = '$Format:%H$'
 
-from qgis.core import (QgsProcessingParameterFeatureSource,
+from qgis.core import (QgsProcessingException,
+                       QgsProcessingParameterFeatureSource,
                        QgsProcessingParameterString,
                        QgsProcessingParameterEnum,
                        QgsProcessingParameterCrs,
@@ -189,6 +190,9 @@ class OgrToPostGis(GdalAlgorithm):
 
     def getConsoleCommands(self, parameters, context, feedback, executing=True):
         ogrLayer, layername = self.getOgrCompatibleSource(self.INPUT, parameters, context, feedback, executing)
+        if not layername:
+            raise QgsProcessingException(self.invalidSourceError(parameters, self.INPUT))
+
         shapeEncoding = self.parameterAsString(parameters, self.SHAPE_ENCODING, context)
         ssrs = self.parameterAsCrs(parameters, self.S_SRS, context).authid()
         tsrs = self.parameterAsCrs(parameters, self.T_SRS, context).authid()

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

@@ -27,7 +27,8 @@ __revision__ = '$Format:%H$'
 
 import os
 
-from qgis.core import (QgsRasterFileWriter,
+from qgis.core import (QgsProcessingException,
+                       QgsRasterFileWriter,
                        QgsProcessingParameterDefinition,
                        QgsProcessingParameterRasterLayer,
                        QgsProcessingParameterBand,
@@ -102,6 +103,8 @@ class aspect(GdalAlgorithm):
     def getConsoleCommands(self, parameters, context, feedback, executing=True):
         arguments = ['aspect']
         inLayer = self.parameterAsRasterLayer(parameters, self.INPUT, context)
+        if inLayer is None:
+            raise QgsProcessingException(self.invalidRasterError(parameters, self.INPUT))
         arguments.append(inLayer.source())
 
         out = self.parameterAsOutputLayer(parameters, self.OUTPUT, context)

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

@@ -30,6 +30,7 @@ import os
 from qgis.PyQt.QtGui import QIcon
 
 from qgis.core import (QgsProcessing,
+                       QgsProcessingException,
                        QgsProcessingParameterDefinition,
                        QgsProcessingParameterRasterLayer,
                        QgsProcessingParameterBand,
@@ -126,6 +127,9 @@ class contour(GdalAlgorithm):
 
     def getConsoleCommands(self, parameters, context, feedback, executing=True):
         inLayer = self.parameterAsRasterLayer(parameters, self.INPUT, context)
+        if inLayer is None:
+            raise QgsProcessingException(self.invalidRasterError(parameters, self.INPUT))
+
         fieldName = self.parameterAsString(parameters, self.FIELD_NAME, context)
         if self.NODATA in parameters and parameters[self.NODATA] is not None:
             nodata = self.parameterAsDouble(parameters, self.NODATA, context)

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

@@ -28,6 +28,7 @@ __revision__ = '$Format:%H$'
 import os
 
 from qgis.core import (QgsRasterFileWriter,
+                       QgsProcessingException,
                        QgsProcessingParameterRasterLayer,
                        QgsProcessingParameterBand,
                        QgsProcessingParameterNumber,
@@ -116,7 +117,11 @@ class fillnodata(GdalAlgorithm):
         arguments.append('-of')
         arguments.append(QgsRasterFileWriter.driverForExtension(os.path.splitext(out)[1]))
 
-        arguments.append(self.parameterAsRasterLayer(parameters, self.INPUT, context).source())
+        raster = self.parameterAsRasterLayer(parameters, self.INPUT, context)
+        if raster is None:
+            raise QgsProcessingException(self.invalidRasterError(parameters, self.INPUT))
+
+        arguments.append(raster.source())
         arguments.append(out)
 
         commands = []

python/plugins/processing/algs/gdal/gdal2tiles.py

@@ -26,7 +26,8 @@ __copyright__ = '(C) 2016, Médéric Ribreux'
 __revision__ = '$Format:%H$'
 
 
-from qgis.core import (QgsProcessingParameterDefinition,
+from qgis.core import (QgsProcessingException,
+                       QgsProcessingParameterDefinition,
                        QgsProcessingParameterRasterLayer,
                        QgsProcessingParameterCrs,
                        QgsProcessingParameterEnum,
@@ -219,6 +220,9 @@ class gdal2tiles(GdalAlgorithm):
             arguments.append('-n')
 
         inLayer = self.parameterAsRasterLayer(parameters, self.INPUT, context)
+        if inLayer is None:
+            raise QgsProcessingException(self.invalidRasterError(parameters, self.INPUT))
+
         arguments.append(inLayer.source())
         arguments.append(self.parameterAsString(parameters, self.OUTPUT, context))
 

python/plugins/processing/algs/gdal/gdal2xyz.py

@@ -26,6 +26,7 @@ __copyright__ = '(C) 2013, Alexander Bruy'
 __revision__ = '$Format:%H$'
 
 from qgis.core import (QgsProcessing,
+                       QgsProcessingException,
                        QgsProcessingParameterRasterLayer,
                        QgsProcessingParameterBand,
                        QgsProcessingParameterBoolean,
@@ -82,7 +83,11 @@ class gdal2xyz(GdalAlgorithm):
         if self.parameterAsBool(parameters, self.CSV, context):
             arguments.append('-csv')
 
-        arguments.append(self.parameterAsRasterLayer(parameters, self.INPUT, context).source())
+        raster = self.parameterAsRasterLayer(parameters, self.INPUT, context)
+        if raster is None:
+            raise QgsProcessingException(self.invalidRasterError(parameters, self.INPUT))
+
+        arguments.append(raster.source())
         arguments.append(self.parameterAsFileOutput(parameters, self.OUTPUT, context))
 
         commands = []

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

@@ -29,7 +29,8 @@ import os
 
 from qgis.PyQt.QtGui import QIcon
 
-from qgis.core import (QgsProcessingParameterRasterLayer,
+from qgis.core import (QgsProcessingException,
+                       QgsProcessingParameterRasterLayer,
                        QgsProcessingParameterEnum,
                        QgsProcessingParameterString,
                        QgsProcessingParameterBoolean,
@@ -110,6 +111,9 @@ class gdaladdo(GdalAlgorithm):
 
     def getConsoleCommands(self, parameters, context, feedback, executing=True):
         inLayer = self.parameterAsRasterLayer(parameters, self.INPUT, context)
+        if inLayer is None:
+            raise QgsProcessingException(self.invalidRasterError(parameters, self.INPUT))
+
         fileName = inLayer.source()
 
         arguments = []

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

@@ -28,7 +28,8 @@ __revision__ = '$Format:%H$'
 import os
 
 from qgis.PyQt.QtGui import QIcon
-from qgis.core import (QgsProcessingParameterRasterLayer,
+from qgis.core import (QgsProcessingException,
+                       QgsProcessingParameterRasterLayer,
                        QgsProcessingParameterBoolean,
                        QgsProcessingParameterFileDestination)
 from processing.algs.gdal.GdalAlgorithm import GdalAlgorithm
@@ -97,7 +98,11 @@ class gdalinfo(GdalAlgorithm):
             arguments.append('-nogcp')
         if self.parameterAsBool(parameters, self.NO_METADATA, context):
             arguments.append('-nomd')
-        arguments.append(self.parameterAsRasterLayer(parameters, self.INPUT, context).source())
+        raster = self.parameterAsRasterLayer(parameters, self.INPUT, context)
+        if raster is None:
+            raise QgsProcessingException(self.invalidRasterError(parameters, self.INPUT))
+
+        arguments.append(raster.source())
         return [self.commandName(), GdalUtils.escapeAndJoin(arguments)]
 
     def processAlgorithm(self, parameters, context, feedback):

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

@@ -29,6 +29,7 @@ __revision__ = '$Format:%H$'
 import os
 
 from qgis.core import (QgsRasterFileWriter,
+                       QgsProcessingException,
                        QgsProcessingParameterDefinition,
                        QgsProcessingParameterRasterLayer,
                        QgsProcessingParameterBand,
@@ -129,6 +130,9 @@ class hillshade(GdalAlgorithm):
     def getConsoleCommands(self, parameters, context, feedback, executing=True):
         arguments = ['hillshade']
         inLayer = self.parameterAsRasterLayer(parameters, self.INPUT, context)
+        if inLayer is None:
+            raise QgsProcessingException(self.invalidRasterError(parameters, self.INPUT))
+
         arguments.append(inLayer.source())
 
         out = self.parameterAsOutputLayer(parameters, self.OUTPUT, context)

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

@@ -30,6 +30,7 @@ import os
 from qgis.PyQt.QtGui import QIcon
 
 from qgis.core import (QgsRasterFileWriter,
+                       QgsProcessingException,
                        QgsProcessingParameterDefinition,
                        QgsProcessingParameterRasterLayer,
                        QgsProcessingParameterBoolean,
@@ -97,6 +98,8 @@ class nearblack(GdalAlgorithm):
 
     def getConsoleCommands(self, parameters, context, feedback, executing=True):
         inLayer = self.parameterAsRasterLayer(parameters, self.INPUT, context)
+        if inLayer is None:
+            raise QgsProcessingException(self.invalidRasterError(parameters, self.INPUT))
 
         arguments = []
         arguments.append(inLayer.source())

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

@@ -26,7 +26,8 @@ __copyright__ = '(C) 2012, Victor Olaya'
 __revision__ = '$Format:%H$'
 
 
-from qgis.core import (QgsProcessingParameterVectorLayer,
+from qgis.core import (QgsProcessingException,
+                       QgsProcessingParameterVectorLayer,
                        QgsProcessingParameterBoolean,
                        QgsProcessingParameterFileDestination)
 from processing.algs.gdal.GdalAlgorithm import GdalAlgorithm
@@ -81,6 +82,9 @@ class ogrinfo(GdalAlgorithm):
             arguments.append('-nomd')
 
         inLayer = self.parameterAsVectorLayer(parameters, self.INPUT, context)
+        if inLayer is None:
+            raise QgsProcessingException(self.invalidSourceError(parameters, self.INPUT))
+
         connectionString = GdalUtils.ogrConnectionString(inLayer.source(), context)
         arguments.append(connectionString)
         return arguments

python/plugins/processing/algs/gdal/pct2rgb.py

@@ -30,6 +30,7 @@ import os
 from qgis.PyQt.QtGui import QIcon
 
 from qgis.core import (QgsRasterFileWriter,
+                       QgsProcessingException,
                        QgsProcessingParameterRasterLayer,
                        QgsProcessingParameterBand,
                        QgsProcessingParameterBoolean,
@@ -83,6 +84,9 @@ class pct2rgb(GdalAlgorithm):
     def getConsoleCommands(self, parameters, context, feedback, executing=True):
         arguments = []
         inLayer = self.parameterAsRasterLayer(parameters, self.INPUT, context)
+        if inLayer is None:
+            raise QgsProcessingException(self.invalidRasterError(parameters, self.INPUT))
+
         arguments.append(inLayer.source())
 
         out = self.parameterAsOutputLayer(parameters, self.OUTPUT, context)

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

@@ -31,6 +31,7 @@ from qgis.PyQt.QtGui import QIcon
 from qgis.PyQt.QtCore import QFileInfo
 
 from qgis.core import (QgsProcessing,
+                       QgsProcessingException,
                        QgsProcessingParameterRasterLayer,
                        QgsProcessingParameterBand,
                        QgsProcessingParameterString,
@@ -91,6 +92,9 @@ class polygonize(GdalAlgorithm):
     def getConsoleCommands(self, parameters, context, feedback, executing=True):
         arguments = []
         inLayer = self.parameterAsRasterLayer(parameters, self.INPUT, context)
+        if inLayer is None:
+            raise QgsProcessingException(self.invalidRasterError(parameters, self.INPUT))
+
         arguments.append(inLayer.source())
 
         outFile = self.parameterAsOutputLayer(parameters, self.OUTPUT, context)

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

@@ -30,6 +30,7 @@ import os
 from qgis.PyQt.QtGui import QIcon
 
 from qgis.core import (QgsRasterFileWriter,
+                       QgsProcessingException,
                        QgsProcessingParameterDefinition,
                        QgsProcessingParameterRasterLayer,
                        QgsProcessingParameterBand,
@@ -136,6 +137,9 @@ class proximity(GdalAlgorithm):
 
     def getConsoleCommands(self, parameters, context, feedback, executing=True):
         inLayer = self.parameterAsRasterLayer(parameters, self.INPUT, context)
+        if inLayer is None:
+            raise QgsProcessingException(self.invalidRasterError(parameters, self.INPUT))
+
         distance = self.parameterAsDouble(parameters, self.MAX_DISTANCE, context)
         replaceValue = self.parameterAsDouble(parameters, self.REPLACE, context)
         if self.NODATA in parameters and parameters[self.NODATA] is not None:

python/plugins/processing/algs/gdal/rgb2pct.py

@@ -31,6 +31,7 @@ import os
 from qgis.PyQt.QtGui import QIcon
 
 from qgis.core import (QgsRasterFileWriter,
+                       QgsProcessingException,
                        QgsProcessingParameterRasterLayer,
                        QgsProcessingParameterNumber,
                        QgsProcessingParameterRasterDestination)
@@ -87,7 +88,11 @@ class rgb2pct(GdalAlgorithm):
         out = self.parameterAsOutputLayer(parameters, self.OUTPUT, context)
         arguments.append('-of')
         arguments.append(QgsRasterFileWriter.driverForExtension(os.path.splitext(out)[1]))
-        arguments.append(self.parameterAsRasterLayer(parameters, self.INPUT, context).source())
+        raster = self.parameterAsRasterLayer(parameters, self.INPUT, context)
+        if raster is None:
+            raise QgsProcessingException(self.invalidRasterError(parameters, self.INPUT))
+
+        arguments.append(raster.source())
         arguments.append(out)
 
         if isWindows():

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

@@ -28,6 +28,7 @@ __revision__ = '$Format:%H$'
 import os
 
 from qgis.core import (QgsRasterFileWriter,
+                       QgsProcessingException,
                        QgsProcessingParameterDefinition,
                        QgsProcessingParameterRasterLayer,
                        QgsProcessingParameterBand,
@@ -91,6 +92,9 @@ class roughness(GdalAlgorithm):
     def getConsoleCommands(self, parameters, context, feedback, executing=True):
         arguments = ['roughness']
         inLayer = self.parameterAsRasterLayer(parameters, self.INPUT, context)
+        if inLayer is None:
+            raise QgsProcessingException(self.invalidRasterError(parameters, self.INPUT))
+
         arguments.append(inLayer.source())
 
         out = self.parameterAsOutputLayer(parameters, self.OUTPUT, context)

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

@@ -30,6 +30,7 @@ import os
 from qgis.PyQt.QtGui import QIcon
 
 from qgis.core import (QgsRasterFileWriter,
+                       QgsProcessingException,
                        QgsProcessingParameterRasterLayer,
                        QgsProcessingParameterNumber,
                        QgsProcessingParameterBoolean,
@@ -111,7 +112,11 @@ class sieve(GdalAlgorithm):
         arguments.append('-of')
         arguments.append(QgsRasterFileWriter.driverForExtension(os.path.splitext(out)[1]))
 
-        arguments.append(self.parameterAsRasterLayer(parameters, self.INPUT, context).source())
+        raster = self.parameterAsRasterLayer(parameters, self.INPUT, context)
+        if raster is None:
+            raise QgsProcessingException(self.invalidRasterError(parameters, self.INPUT))
+
+        arguments.append(raster.source())
         arguments.append(out)
 
         commands = []

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

@@ -29,6 +29,7 @@ __revision__ = '$Format:%H$'
 import os
 
 from qgis.core import (QgsRasterFileWriter,
+                       QgsProcessingException,
                        QgsProcessingParameterDefinition,
                        QgsProcessingParameterRasterLayer,
                        QgsProcessingParameterBand,
@@ -106,6 +107,9 @@ class slope(GdalAlgorithm):
     def getConsoleCommands(self, parameters, context, feedback, executing=True):
         arguments = ['slope']
         inLayer = self.parameterAsRasterLayer(parameters, self.INPUT, context)
+        if inLayer is None:
+            raise QgsProcessingException(self.invalidRasterError(parameters, self.INPUT))
+
         arguments.append(inLayer.source())
 
         out = self.parameterAsOutputLayer(parameters, self.OUTPUT, context)

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

@@ -28,7 +28,8 @@ __revision__ = '$Format:%H$'
 
 import os
 
-from qgis.core import (QgsProcessingParameterDefinition,
+from qgis.core import (QgsProcessingException,
+                       QgsProcessingParameterDefinition,
                        QgsProcessingParameterRasterLayer,
                        QgsProcessingParameterBand,
                        QgsProcessingParameterString,
@@ -90,6 +91,9 @@ class tpi(GdalAlgorithm):
     def getConsoleCommands(self, parameters, context, feedback, executing=True):
         arguments = ['TPI']
         inLayer = self.parameterAsRasterLayer(parameters, self.INPUT, context)
+        if inLayer is None:
+            raise QgsProcessingException(self.invalidRasterError(parameters, self.INPUT))
+
         arguments.append(inLayer.source())
         out = self.parameterAsOutputLayer(parameters, self.OUTPUT, context)
         arguments.append(out)

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

@@ -30,6 +30,7 @@ import os
 from qgis.PyQt.QtGui import QIcon
 
 from qgis.core import (QgsRasterFileWriter,
+                       QgsProcessingException,
                        QgsProcessingParameterDefinition,
                        QgsProcessingParameterRasterLayer,
                        QgsProcessingParameterNumber,
@@ -115,6 +116,9 @@ class translate(GdalAlgorithm):
 
     def getConsoleCommands(self, parameters, context, feedback, executing=True):
         inLayer = self.parameterAsRasterLayer(parameters, self.INPUT, context)
+        if inLayer is None:
+            raise QgsProcessingException(self.invalidRasterError(parameters, self.INPUT))
+
         out = self.parameterAsOutputLayer(parameters, self.OUTPUT, context)
         if self.NODATA in parameters and parameters[self.NODATA] is not None:
             nodata = self.parameterAsDouble(parameters, self.NODATA, context)

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

@@ -27,7 +27,8 @@ __revision__ = '$Format:%H$'
 
 import os
 
-from qgis.core import (QgsProcessingParameterDefinition,
+from qgis.core import (QgsProcessingException,
+                       QgsProcessingParameterDefinition,
                        QgsProcessingParameterRasterLayer,
                        QgsProcessingParameterBand,
                        QgsProcessingParameterString,
@@ -89,6 +90,9 @@ class tri(GdalAlgorithm):
     def getConsoleCommands(self, parameters, context, feedback, executing=True):
         arguments = ['TRI']
         inLayer = self.parameterAsRasterLayer(parameters, self.INPUT, context)
+        if inLayer is None:
+            raise QgsProcessingException(self.invalidRasterError(parameters, self.INPUT))
+
         arguments.append(inLayer.source())
         out = self.parameterAsOutputLayer(parameters, self.OUTPUT, context)
         arguments.append(out)

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

@@ -29,6 +29,7 @@ import os
 
 from qgis.PyQt.QtGui import QIcon
 from qgis.core import (QgsRasterFileWriter,
+                       QgsProcessingException,
                        QgsProcessingParameterDefinition,
                        QgsProcessingParameterRasterLayer,
                        QgsProcessingParameterCrs,
@@ -163,6 +164,9 @@ class warp(GdalAlgorithm):
 
     def getConsoleCommands(self, parameters, context, feedback, executing=True):
         inLayer = self.parameterAsRasterLayer(parameters, self.INPUT, context)
+        if inLayer is None:
+            raise QgsProcessingException(self.invalidRasterError(parameters, self.INPUT))
+
         out = self.parameterAsOutputLayer(parameters, self.OUTPUT, context)
         sourceCrs = self.parameterAsCrs(parameters, self.SOURCE_CRS, context)
         targetCrs = self.parameterAsCrs(parameters, self.TARGET_CRS, context)

python/plugins/processing/tests/GdalAlgorithmsTest.py

@@ -52,7 +52,7 @@ from qgis.core import (QgsProcessingContext,
                        QgsPointXY,
                        QgsProject,
                        QgsRectangle,
-                       QgsProcessingUtils,
+                       QgsProcessingException,
                        QgsProcessingFeatureSourceDefinition)
 import nose2
 import os
@@ -90,6 +90,18 @@ class TestGdalAlgorithms(unittest.TestCase, AlgorithmsTestBase.AlgorithmsTest):
         for a in p.algorithms():
             self.assertTrue(a.commandName(), 'Algorithm {} has no commandName!'.format(a.id()))
 
+    def testNoParameters(self):
+        # Test that algorithms throw QgsProcessingExceptions and not base Python
+        # exceptions when no parameters specified
+        p = QgsApplication.processingRegistry().providerById('gdal')
+        context = QgsProcessingContext()
+        feedback = QgsProcessingFeedback()
+        for a in p.algorithms():
+            try:
+                a.getConsoleCommands({}, context, feedback)
+            except QgsProcessingException:
+                pass
+
     def testGetOgrCompatibleSourceFromMemoryLayer(self):
         # create a memory layer and add to project and context
         layer = QgsVectorLayer("Point?field=fldtxt:string&field=fldint:integer",

python/plugins/processing/tools/postgis.py

@@ -30,7 +30,10 @@ import psycopg2.extensions  # For isolation levels
 import re
 import os
 
-from qgis.core import QgsDataSourceUri, QgsCredentials, QgsSettings
+from qgis.core import (QgsProcessingException,
+                       QgsDataSourceUri,
+                       QgsCredentials,
+                       QgsSettings)
 
 from qgis.PyQt.QtCore import QCoreApplication
 
@@ -44,7 +47,7 @@ def uri_from_name(conn_name):
     settings.beginGroup(u"/PostgreSQL/connections/%s" % conn_name)
 
     if not settings.contains("database"):  # non-existent entry?
-        raise DbError(QCoreApplication.translate("PostGIS", 'There is no defined database connection "{0}".').format(conn_name))
+        raise QgsProcessingException(QCoreApplication.translate("PostGIS", 'There is no defined database connection "{0}".').format(conn_name))
 
     uri = QgsDataSourceUri()
 
@@ -126,19 +129,6 @@ class TableIndex(object):
         self.columns = list(map(int, columns.split(' ')))
 
 
-class DbError(Exception):
-
-    def __init__(self, message, query=None):
-        self.message = message
-        self.query = query
-
-    def __str__(self):
-        text = "MESSAGE: {}".format(self.message)
-        if self.query:
-            text = "{}\nQUERY: {}".format(text, self.query)
-        return text
-
-
 class TableField(object):
 
     def __init__(self, name, data_type, is_null=None, default=None,
@@ -207,7 +197,7 @@ class GeoDB(object):
                 break
             except psycopg2.OperationalError as e:
                 if i == 3:
-                    raise DbError(str(e))
+                    raise QgsProcessingException(str(e))
 
                 err = str(e)
                 user = self.uri.username()
@@ -217,7 +207,7 @@ class GeoDB(object):
                                                                      password,
                                                                      err)
                 if not ok:
-                    raise DbError(QCoreApplication.translate("PostGIS", 'Action canceled by user'))
+                    raise QgsProcessingException(QCoreApplication.translate("PostGIS", 'Action canceled by user'))
                 if user:
                     self.uri.setUsername(user)
                 if password:
@@ -823,8 +813,8 @@ class GeoDB(object):
         try:
             cursor.execute(sql)
         except psycopg2.Error as e:
-            raise DbError(str(e),
+            raise QgsProcessingException(str(e) + ' QUERY: ' +
-                          e.cursor.query.decode(e.cursor.connection.encoding))
+                                         e.cursor.query.decode(e.cursor.connection.encoding))
 
     def _exec_sql_and_commit(self, sql):
         """Tries to execute and commit some action, on error it rolls