def _copy_fields(self,
sink: QgsFeatureSink,
extent: Optional[QgsRectangle] = None) -> None:
total = (100.0 / self.layer.featureCount()
if self.layer.featureCount() > 0 else 100)
if extent is not None and not extent.isEmpty():
self.feedback.pushDebugInfo(f"Extent: {extent.toString()}")
source_index = QgsSpatialIndex(self.layer, self.feedback)
ids = source_index.intersects(extent)
features = self.layer.getFeatures(
QgsFeatureRequest().setFilterFids(ids))
else:
features = self.layer.getFeatures()
f: QgsFeature
for current, f in enumerate(features):
if self.feedback.isCanceled():
break
if not f.hasGeometry():
sink.addFeature(f, QgsFeatureSink.FastInsert)
else:
feat = QgsFeature()
attributes = self._get_attributes_for_feature(f)
feat.setAttributes(attributes)
feat.setGeometry(f.geometry())
succeeded = sink.addFeature(feat, QgsFeatureSink.FastInsert)
if not succeeded:
raise ValueError(
tr(
"Could not add feature to target layer. Attributes: {}",
attributes,
))
self.feedback.setProgress(int(current * total))
def execute_in_place_run(alg,
parameters,
context=None,
feedback=None,
raise_exceptions=False):
"""Executes an algorithm modifying features in-place in the input layer.
:param alg: algorithm to run
:type alg: QgsProcessingAlgorithm
:param parameters: parameters of the algorithm
:type parameters: dict
:param context: context, defaults to None
:type context: QgsProcessingContext, optional
:param feedback: feedback, defaults to None
:type feedback: QgsProcessingFeedback, optional
:param raise_exceptions: useful for testing, if True exceptions are raised, normally exceptions will be forwarded to the feedback
:type raise_exceptions: boo, default to False
:raises QgsProcessingException: raised when there is no active layer, or it cannot be made editable
:return: a tuple with true if success and results
:rtype: tuple
"""
if feedback is None:
feedback = QgsProcessingFeedback()
if context is None:
context = dataobjects.createContext(feedback)
# Only feature based algs have sourceFlags
try:
if alg.sourceFlags(
) & QgsProcessingFeatureSource.FlagSkipGeometryValidityChecks:
context.setInvalidGeometryCheck(QgsFeatureRequest.GeometryNoCheck)
except AttributeError:
pass
active_layer = parameters['INPUT']
# Run some checks and prepare the layer for in-place execution by:
# - getting the active layer and checking that it is a vector
# - making the layer editable if it was not already
# - selecting all features if none was selected
# - checking in-place support for the active layer/alg/parameters
# If one of the check fails and raise_exceptions is True an exception
# is raised, else the execution is aborted and the error reported in
# the feedback
try:
if active_layer is None:
raise QgsProcessingException(tr("There is no active layer."))
if not isinstance(active_layer, QgsVectorLayer):
raise QgsProcessingException(
tr("Active layer is not a vector layer."))
if not active_layer.isEditable():
if not active_layer.startEditing():
raise QgsProcessingException(
tr("Active layer is not editable (and editing could not be turned on)."
))
if not alg.supportInPlaceEdit(active_layer):
raise QgsProcessingException(
tr("Selected algorithm and parameter configuration are not compatible with in-place modifications."
))
except QgsProcessingException as e:
if raise_exceptions:
raise e
QgsMessageLog.logMessage(str(sys.exc_info()[0]), 'Processing',
Qgis.Critical)
if feedback is not None:
feedback.reportError(getattr(e, 'msg', str(e)), fatalError=True)
return False, {}
if not active_layer.selectedFeatureIds():
active_layer.selectAll()
# Make sure we are working on selected features only
parameters['INPUT'] = QgsProcessingFeatureSourceDefinition(
active_layer.id(), True)
parameters['OUTPUT'] = 'memory:'
req = QgsFeatureRequest(QgsExpression(r"$id < 0"))
req.setFlags(QgsFeatureRequest.NoGeometry)
req.setSubsetOfAttributes([])
# Start the execution
# If anything goes wrong and raise_exceptions is True an exception
# is raised, else the execution is aborted and the error reported in
# the feedback
try:
new_feature_ids = []
active_layer.beginEditCommand(alg.displayName())
# Checks whether the algorithm has a processFeature method
if hasattr(alg, 'processFeature'): # in-place feature editing
# Make a clone or it will crash the second time the dialog
# is opened and run
alg = alg.create({'IN_PLACE': True})
if not alg.prepare(parameters, context, feedback):
raise QgsProcessingException(
tr("Could not prepare selected algorithm."))
# Check again for compatibility after prepare
if not alg.supportInPlaceEdit(active_layer):
raise QgsProcessingException(
tr("Selected algorithm and parameter configuration are not compatible with in-place modifications."
))
# some algorithms have logic in outputFields/outputCrs/outputWkbType which they require to execute before
# they can start processing features
_ = alg.outputFields(active_layer.fields())
_ = alg.outputWkbType(active_layer.wkbType())
_ = alg.outputCrs(active_layer.crs())
field_idxs = range(len(active_layer.fields()))
iterator_req = QgsFeatureRequest(active_layer.selectedFeatureIds())
iterator_req.setInvalidGeometryCheck(
context.invalidGeometryCheck())
feature_iterator = active_layer.getFeatures(iterator_req)
step = 100 / len(active_layer.selectedFeatureIds()
) if active_layer.selectedFeatureIds() else 1
for current, f in enumerate(feature_iterator):
if feedback.isCanceled():
break
# need a deep copy, because python processFeature implementations may return
# a shallow copy from processFeature
input_feature = QgsFeature(f)
new_features = alg.processFeature(input_feature, context,
feedback)
new_features = QgsVectorLayerUtils.makeFeaturesCompatible(
new_features, active_layer)
if len(new_features) == 0:
active_layer.deleteFeature(f.id())
elif len(new_features) == 1:
new_f = new_features[0]
if not f.geometry().equals(new_f.geometry()):
active_layer.changeGeometry(f.id(), new_f.geometry())
if f.attributes() != new_f.attributes():
active_layer.changeAttributeValues(
f.id(), dict(zip(field_idxs, new_f.attributes())),
dict(zip(field_idxs, f.attributes())))
new_feature_ids.append(f.id())
else:
active_layer.deleteFeature(f.id())
# Get the new ids
old_ids = set(
[f.id() for f in active_layer.getFeatures(req)])
# If multiple new features were created, we need to pass
# them to createFeatures to manage constraints correctly
features_data = []
for f in new_features:
features_data.append(
QgsVectorLayerUtils.QgsFeatureData(
f.geometry(), dict(enumerate(f.attributes()))))
new_features = QgsVectorLayerUtils.createFeatures(
active_layer, features_data,
context.expressionContext())
if not active_layer.addFeatures(new_features):
raise QgsProcessingException(
tr("Error adding processed features back into the layer."
))
new_ids = set(
[f.id() for f in active_layer.getFeatures(req)])
new_feature_ids += list(new_ids - old_ids)
feedback.setProgress(int((current + 1) * step))
results, ok = {'__count': current + 1}, True
else: # Traditional 'run' with delete and add features cycle
# There is no way to know if some features have been skipped
# due to invalid geometries
if context.invalidGeometryCheck(
) == QgsFeatureRequest.GeometrySkipInvalid:
selected_ids = active_layer.selectedFeatureIds()
else:
selected_ids = []
results, ok = alg.run(parameters,
context,
feedback,
configuration={'IN_PLACE': True})
if ok:
result_layer = QgsProcessingUtils.mapLayerFromString(
results['OUTPUT'], context)
# TODO: check if features have changed before delete/add cycle
new_features = []
# Check if there are any skipped features
if context.invalidGeometryCheck(
) == QgsFeatureRequest.GeometrySkipInvalid:
missing_ids = list(
set(selected_ids) - set(result_layer.allFeatureIds()))
if missing_ids:
for f in active_layer.getFeatures(
QgsFeatureRequest(missing_ids)):
if not f.geometry().isGeosValid():
new_features.append(f)
active_layer.deleteFeatures(active_layer.selectedFeatureIds())
regenerate_primary_key = result_layer.customProperty(
'OnConvertFormatRegeneratePrimaryKey', False)
sink_flags = QgsFeatureSink.SinkFlags(QgsFeatureSink.RegeneratePrimaryKey) if regenerate_primary_key \
else QgsFeatureSink.SinkFlags()
for f in result_layer.getFeatures():
new_features.extend(
QgsVectorLayerUtils.makeFeaturesCompatible(
[f], active_layer, sink_flags))
# Get the new ids
old_ids = set([f.id() for f in active_layer.getFeatures(req)])
if not active_layer.addFeatures(new_features):
raise QgsProcessingException(
tr("Error adding processed features back into the layer."
))
new_ids = set([f.id() for f in active_layer.getFeatures(req)])
new_feature_ids += list(new_ids - old_ids)
results['__count'] = len(new_feature_ids)
active_layer.endEditCommand()
if ok and new_feature_ids:
active_layer.selectByIds(new_feature_ids)
elif not ok:
active_layer.rollBack()
return ok, results
except QgsProcessingException as e:
active_layer.endEditCommand()
active_layer.rollBack()
if raise_exceptions:
raise e
QgsMessageLog.logMessage(str(sys.exc_info()[0]), 'Processing',
Qgis.Critical)
if feedback is not None:
feedback.reportError(getattr(e, 'msg', str(e)), fatalError=True)
return False, {}