add native add history metadata algorithm

src/analysis/processing/qgsmetadataalgorithms.cpp

@@ -248,4 +248,75 @@ QVariantMap QgsExportLayerMetadataAlgorithm::processAlgorithm( const QVariantMap
   return results;
 }
 
+///
+
+QString QgsAddHistoryMetadataAlgorithm::name() const
+{
+  return QStringLiteral( "addhistorymetadata" );
+}
+
+QString QgsAddHistoryMetadataAlgorithm::displayName() const
+{
+  return QObject::tr( "Add history metadata" );
+}
+
+QStringList QgsAddHistoryMetadataAlgorithm::tags() const
+{
+  return QObject::tr( "add,history,metadata" ).split( ',' );
+}
+
+QString QgsAddHistoryMetadataAlgorithm::group() const
+{
+  return QObject::tr( "Metadata tools" );
+}
+
+QString QgsAddHistoryMetadataAlgorithm::groupId() const
+{
+  return QStringLiteral( "metadatatools" );
+}
+
+QString QgsAddHistoryMetadataAlgorithm::shortHelpString() const
+{
+  return QObject::tr( "Adds a new history entry to the layer's metadata." );
+}
+
+QgsAddHistoryMetadataAlgorithm *QgsAddHistoryMetadataAlgorithm::createInstance() const
+{
+  return new QgsAddHistoryMetadataAlgorithm();
+}
+
+void QgsAddHistoryMetadataAlgorithm::initAlgorithm( const QVariantMap & )
+{
+  addParameter( new QgsProcessingParameterMapLayer( QStringLiteral( "INPUT" ), QObject::tr( "Layer" ) ) );
+  addParameter( new QgsProcessingParameterString( QStringLiteral( "HISTORY" ), QObject::tr( "History entry" ) ) );
+  addOutput( new QgsProcessingOutputMapLayer( QStringLiteral( "OUTPUT" ), QObject::tr( "Updated" ) ) );
+}
+
+bool QgsAddHistoryMetadataAlgorithm::prepareAlgorithm( const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback * )
+{
+  QgsMapLayer *layer = parameterAsLayer( parameters, QStringLiteral( "INPUT" ), context );
+  const QString history = parameterAsString( parameters, QStringLiteral( "HISTORY" ), context );
+
+  if ( !layer )
+    throw QgsProcessingException( QObject::tr( "Invalid input layer" ) );
+
+  mLayerId = layer->id();
+
+  std::unique_ptr<QgsLayerMetadata> md( layer->metadata().clone() );
+  md->addHistoryItem( history );
+  layer->setMetadata( *md.get() );
+
+  return true;
+}
+
+QVariantMap QgsAddHistoryMetadataAlgorithm::processAlgorithm( const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback * )
+{
+  Q_UNUSED( parameters );
+  Q_UNUSED( context );
+
+  QVariantMap results;
+  results.insert( QStringLiteral( "OUTPUT" ), mLayerId );
+  return results;
+}
+
 ///@endcond

src/analysis/processing/qgsmetadataalgorithms.h

@@ -97,6 +97,30 @@ class QgsExportLayerMetadataAlgorithm : public QgsProcessingAlgorithm
     QString mLayerId;
 };
 
+/**
+ * Native add history metadata algorithm.
+ */
+class QgsAddHistoryMetadataAlgorithm : public QgsProcessingAlgorithm
+{
+  public:
+    QgsAddHistoryMetadataAlgorithm() = default;
+    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;
+    QgsAddHistoryMetadataAlgorithm *createInstance() const override SIP_FACTORY;
+
+  protected:
+    bool prepareAlgorithm( const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback *feedback ) override;
+    QVariantMap processAlgorithm( const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback * ) override;
+
+  private:
+    QString mLayerId;
+};
+
 ///@endcond PRIVATE
 
 #endif // QGSMETADATAALGORITHMS_H

src/analysis/processing/qgsnativealgorithms.cpp

@@ -292,6 +292,7 @@ Qgis::ProcessingProviderFlags QgsNativeAlgorithms::flags() const
 void QgsNativeAlgorithms::loadAlgorithms()
 {
   const QgsScopedRuntimeProfile profile( QObject::tr( "QGIS native provider" ) );
+  addAlgorithm( new QgsAddHistoryMetadataAlgorithm() );
   addAlgorithm( new QgsAddIncrementalFieldAlgorithm() );
   addAlgorithm( new QgsAddTableFieldAlgorithm() );
   addAlgorithm( new QgsAddXYFieldsAlgorithm() );

tests/src/analysis/testqgsprocessingalgspt2.cpp

@@ -107,6 +107,7 @@ class TestQgsProcessingAlgsPt2 : public QgsTest
     void copyMetadata();
     void applyMetadata();
     void exportMetadata();
+    void addHistoryMetadata();
 
   private:
     QString mPointLayerPath;
@@ -1988,6 +1989,49 @@ void TestQgsProcessingAlgsPt2::exportMetadata()
   QCOMPARE( md.abstract(), exportedMetadata.abstract() );
 }
 
+void TestQgsProcessingAlgsPt2::addHistoryMetadata()
+{
+  std::unique_ptr<QgsVectorLayer> layer = std::make_unique<QgsVectorLayer>( QStringLiteral( "Point?crs=epsg:4326&field=pk:int&field=col1:string" ), QStringLiteral( "input" ), QStringLiteral( "memory" ) );
+  QVERIFY( layer->isValid() );
+
+  QgsLayerMetadata md;
+  md.setTitle( QStringLiteral( "Title" ) );
+  md.setAbstract( QStringLiteral( "Abstract" ) );
+  layer->setMetadata( md );
+
+  std::unique_ptr<QgsProcessingAlgorithm> alg( QgsApplication::processingRegistry()->createAlgorithmById( QStringLiteral( "native:addhistorymetadata" ) ) );
+  QVERIFY( alg != nullptr );
+
+  QVariantMap parameters;
+  parameters.insert( QStringLiteral( "INPUT" ), QVariant::fromValue( layer.get() ) );
+  parameters.insert( QStringLiteral( "HISTORY" ), QStringLiteral( "do something" ) );
+
+  bool ok = false;
+  std::unique_ptr<QgsProcessingContext> context = std::make_unique<QgsProcessingContext>();
+  QgsProcessingFeedback feedback;
+  QVariantMap results;
+  results = alg->run( parameters, *context, &feedback, &ok );
+  QVERIFY( ok );
+
+  QCOMPARE( results.value( QStringLiteral( "OUTPUT" ) ), layer->id() );
+
+  QStringList history = layer->metadata().history();
+  QCOMPARE( history.count(), 1 );
+  QCOMPARE( history.at( 0 ), QStringLiteral( "do something" ) );
+
+  parameters[QStringLiteral( "HISTORY" )] = QStringLiteral( "do something else" );
+
+  ok = false;
+  results = alg->run( parameters, *context, &feedback, &ok );
+  QVERIFY( ok );
+
+  QCOMPARE( results.value( QStringLiteral( "OUTPUT" ) ), layer->id() );
+
+  history = layer->metadata().history();
+  QCOMPARE( history.count(), 2 );
+  QCOMPARE( history.at( 0 ), QStringLiteral( "do something" ) );
+  QCOMPARE( history.at( 1 ), QStringLiteral( "do something else" ) );
+}
 
 QGSTEST_MAIN( TestQgsProcessingAlgsPt2 )
 #include "testqgsprocessingalgspt2.moc"