[processing] port truncate table to C++

qgis · Dec 9, 2019 · 4622661 · 4622661
1 parent c974125
commit 4622661
Show file tree

Hide file tree

Showing 8 changed files with 147 additions and 81 deletions.
diff --git a/python/plugins/processing/algs/help/qgis.yaml b/python/plugins/processing/algs/help/qgis.yaml
@@ -432,14 +432,6 @@ qgis:topologicalcoloring: >
 
   A minimum number of colors can be specified if desired. The color index is saved to a new attribute named color_id.
 
-qgis:translate: >
-  This algorithm moves the geometries within a layer, by offsetting them with a specified x and y displacement.
-
-qgis:truncatetable: >
-  This algorithm truncates a layer, by deleting all features from within the layer.
-
-  Warning - this algorithm modifies the layer in place, and deleted features cannot be restored!
-
 qgis:variabledistancebuffer: >
   This algorithm computes a buffer area for all the features in an input layer. The size of the buffer for a given feature is defined by an attribute, so it allows different features to have different buffer sizes.
 

diff --git a/python/plugins/processing/algs/qgis/QgisAlgorithmProvider.py b/python/plugins/processing/algs/qgis/QgisAlgorithmProvider.py
@@ -95,7 +95,6 @@
 from .TilesXYZ import TilesXYZAlgorithmDirectory, TilesXYZAlgorithmMBTiles
 from .TinInterpolation import TinInterpolation
 from .TopoColors import TopoColor
-from .TruncateTable import TruncateTable
 from .UniqueValues import UniqueValues
 from .VariableDistanceBuffer import VariableDistanceBuffer
 from .VectorLayerHistogram import VectorLayerHistogram
@@ -183,7 +182,6 @@ def getAlgs(self):
                 TilesXYZAlgorithmMBTiles(),
                 TinInterpolation(),
                 TopoColor(),
-                TruncateTable(),
                 UniqueValues(),
                 VariableDistanceBuffer(),
                 VectorLayerHistogram(),

diff --git a/python/plugins/processing/algs/qgis/TruncateTable.py b/python/plugins/processing/algs/qgis/TruncateTable.py
diff --git a/python/plugins/processing/tests/testdata/qgis_algorithm_tests2.yaml b/python/plugins/processing/tests/testdata/qgis_algorithm_tests2.yaml
@@ -1932,7 +1932,7 @@ tests:
         type: vector
         in_place_result: true
 
-  - algorithm: qgis:truncatetable
+  - algorithm: native:truncatetable
     name: Truncate table
     params:
       INPUT:

diff --git a/src/analysis/CMakeLists.txt b/src/analysis/CMakeLists.txt
@@ -147,6 +147,7 @@ SET(QGIS_ANALYSIS_SRCS
   processing/qgsalgorithmtransect.cpp
   processing/qgsalgorithmtransform.cpp
   processing/qgsalgorithmtranslate.cpp
+  processing/qgsalgorithmtruncatetable.cpp
   processing/qgsalgorithmunion.cpp
   processing/qgsalgorithmuniquevalueindex.cpp
   processing/qgsalgorithmvectorize.cpp

diff --git a/src/analysis/processing/qgsalgorithmtruncatetable.cpp b/src/analysis/processing/qgsalgorithmtruncatetable.cpp
@@ -0,0 +1,88 @@
+/***************************************************************************
+                         qgsalgorithmtruncatetable.cpp
+                         ---------------------
+    begin                : December 2019
+    copyright            : (C) 2019 by Alexander Bruy
+    email                : alexander dot bruy at gmail dot com
+ ***************************************************************************/
+
+/***************************************************************************
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ *                                                                         *
+ ***************************************************************************/
+
+#include "qgsalgorithmtruncatetable.h"
+#include "qgsvectorlayer.h"
+
+///@cond PRIVATE
+
+QString QgsTruncateTableAlgorithm::name() const
+{
+  return QStringLiteral( "truncatetable" );
+}
+
+QString QgsTruncateTableAlgorithm::displayName() const
+{
+  return QObject::tr( "Truncate table" );
+}
+
+QStringList QgsTruncateTableAlgorithm::tags() const
+{
+  return QObject::tr( "empty,delete,layer,clear,features" ).split( ',' );
+}
+
+QString QgsTruncateTableAlgorithm::group() const
+{
+  return QObject::tr( "Vector general" );
+}
+
+QString QgsTruncateTableAlgorithm::groupId() const
+{
+  return QStringLiteral( "vectorgeneral" );
+}
+
+QString QgsTruncateTableAlgorithm::shortHelpString() const
+{
+  return QObject::tr( "This algorithm truncates a layer, by deleting all features from within the layer." )
+         + QStringLiteral( "\n\n" )
+         + QObject::tr( "Warning — this algorithm modifies the layer in place, and deleted features cannot be restored!" );
+}
+
+QgsProcessingAlgorithm::Flags QgsTruncateTableAlgorithm::flags() const
+{
+  return QgsProcessingAlgorithm::flags() | QgsProcessingAlgorithm::FlagNoThreading;
+}
+
+QgsTruncateTableAlgorithm *QgsTruncateTableAlgorithm::createInstance() const
+{
+  return new QgsTruncateTableAlgorithm();
+}
+
+void QgsTruncateTableAlgorithm::initAlgorithm( const QVariantMap & )
+{
+  addParameter( new QgsProcessingParameterVectorLayer( QStringLiteral( "INPUT" ), QObject::tr( "Input layer" ) ) );
+  addOutput( new QgsProcessingOutputVectorLayer( QStringLiteral( "OUTPUT" ), QObject::tr( "Truncated layer" ) ) );
+}
+
+QVariantMap QgsTruncateTableAlgorithm::processAlgorithm( const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback * )
+{
+  QgsVectorLayer *layer = parameterAsVectorLayer( parameters, QStringLiteral( "INPUT" ), context );
+
+  if ( !layer )
+    throw QgsProcessingException( QObject::tr( "Invalid input layer" ) );
+
+  if ( !layer->dataProvider()->truncate() )
+  {
+    throw QgsProcessingException( QObject::tr( "Could not truncate table." ) );
+  }
+
+  QVariantMap outputs;
+  outputs.insert( QStringLiteral( "OUTPUT" ), layer->id() );
+  return outputs;
+}
+
+///@endcond
diff --git a/src/analysis/processing/qgsalgorithmtruncatetable.h b/src/analysis/processing/qgsalgorithmtruncatetable.h
@@ -0,0 +1,55 @@
+/***************************************************************************
+                         qgsalgorithmtruncatetable.h
+                         ------------------------------
+    begin                : December 2019
+    copyright            : (C) 2019 by Alexander Bruy
+    email                : alexander dot bruy at gmail dot com
+ ***************************************************************************/
+
+/***************************************************************************
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ *                                                                         *
+ ***************************************************************************/
+
+#ifndef QGSALGORITHMTRUNCATETABLE_H
+#define QGSALGORITHMTRUNCATETABLE_H
+
+#define SIP_NO_FILE
+
+#include "qgis_sip.h"
+#include "qgsprocessingalgorithm.h"
+
+///@cond PRIVATE
+
+/**
+ * Native truncate table algorithm.
+ */
+class QgsTruncateTableAlgorithm : public QgsProcessingAlgorithm
+{
+
+  public:
+
+    QgsTruncateTableAlgorithm() = default;
+    Flags flags() const override;
+    QString name() const override;
+    QString displayName() const override;
+    QStringList tags() const override;
+    QString group() const override;
+    QString groupId() const override;
+    QString shortHelpString() const override;
+    void initAlgorithm( const QVariantMap &configuration = QVariantMap() ) override;
+    QgsTruncateTableAlgorithm *createInstance() const override SIP_FACTORY;
+
+  protected:
+
+    QVariantMap processAlgorithm( const QVariantMap &parameters,
+                                  QgsProcessingContext &context, QgsProcessingFeedback *feedback ) override;
+};
+
+///@endcond PRIVATE
+
+#endif // QGSALGORITHMTRUNCATETABLE_H
diff --git a/src/analysis/processing/qgsnativealgorithms.cpp b/src/analysis/processing/qgsnativealgorithms.cpp
@@ -141,6 +141,7 @@
 #include "qgsalgorithmtransect.h"
 #include "qgsalgorithmtransform.h"
 #include "qgsalgorithmtranslate.h"
+#include "qgsalgorithmtruncatetable.h"
 #include "qgsalgorithmunion.h"
 #include "qgsalgorithmuniquevalueindex.h"
 #include "qgsalgorithmvectorize.h"
@@ -332,6 +333,7 @@ void QgsNativeAlgorithms::loadAlgorithms()
   addAlgorithm( new QgsTransectAlgorithm() );
   addAlgorithm( new QgsTransformAlgorithm() );
   addAlgorithm( new QgsTranslateAlgorithm() );
+  addAlgorithm( new QgsTruncateTableAlgorithm() );
   addAlgorithm( new QgsUnionAlgorithm() );
   addAlgorithm( new QgsVariableWidthBufferByMAlgorithm() );
   addAlgorithm( new QgsWedgeBuffersAlgorithm() );