[FEATURE][processing] Add "Save layer styles into GeoPackage" option …

…for Package Layers algorithm Allows embedding of the current layer styles into the packaged layers as the default layer styles.
qgis · May 14, 2019 · 2d64437 · 2d64437
1 parent 95f8bfb
commit 2d64437
Show file tree

Hide file tree

Showing 2 changed files with 49 additions and 5 deletions.
diff --git a/src/analysis/processing/qgsalgorithmpackage.cpp b/src/analysis/processing/qgsalgorithmpackage.cpp
@@ -20,6 +20,7 @@
 #include "qgsogrutils.h"
 #include "qgsvectorfilewriter.h"
 #include "qgsvectorlayer.h"
+#include "qgssettings.h"
 
 ///@cond PRIVATE
 
@@ -53,6 +54,7 @@ void QgsPackageAlgorithm::initAlgorithm( const QVariantMap & )
   addParameter( new QgsProcessingParameterMultipleLayers( QStringLiteral( "LAYERS" ), QObject::tr( "Input layers" ), QgsProcessing::TypeVector ) );
   addParameter( new QgsProcessingParameterFileDestination( QStringLiteral( "OUTPUT" ), QObject::tr( "Destination GeoPackage" ), QObject::tr( "GeoPackage files (*.gpkg)" ) ) );
   addParameter( new QgsProcessingParameterBoolean( QStringLiteral( "OVERWRITE" ), QObject::tr( "Overwrite existing GeoPackage" ), false ) );
+  addParameter( new QgsProcessingParameterBoolean( QStringLiteral( "SAVE_STYLES" ), QObject::tr( "Save layer styles into GeoPackage" ), true ) );
   addOutput( new QgsProcessingOutputMultipleLayers( QStringLiteral( "OUTPUT_LAYERS" ), QObject::tr( "Layers within new package" ) ) );
 }
 
@@ -68,7 +70,8 @@ QgsPackageAlgorithm *QgsPackageAlgorithm::createInstance() const
 
 QVariantMap QgsPackageAlgorithm::processAlgorithm( const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback *feedback )
 {
-  bool overwrite = parameterAsBoolean( parameters, QStringLiteral( "OVERWRITE" ), context );
+  const bool overwrite = parameterAsBoolean( parameters, QStringLiteral( "OVERWRITE" ), context );
+  const bool saveStyles = parameterAsBoolean( parameters, QStringLiteral( "SAVE_STYLES" ), context );
   QString packagePath = parameterAsString( parameters, QStringLiteral( "OUTPUT" ), context );
   if ( packagePath.isEmpty() )
     throw QgsProcessingException( QObject::tr( "No output file specified." ) );
@@ -123,7 +126,7 @@ QVariantMap QgsPackageAlgorithm::processAlgorithm( const QVariantMap &parameters
       case QgsMapLayerType::VectorLayer:
       {
         if ( !packageVectorLayer( qobject_cast< QgsVectorLayer * >( layer ), packagePath,
-                                  context, &multiStepFeedback ) )
+                                  context, &multiStepFeedback, saveStyles ) )
           errored = true;
         else
           outputLayers.append( QStringLiteral( "%1|layername=%2" ).arg( packagePath, layer->name() ) );
@@ -162,7 +165,7 @@ QVariantMap QgsPackageAlgorithm::processAlgorithm( const QVariantMap &parameters
 }
 
 bool QgsPackageAlgorithm::packageVectorLayer( QgsVectorLayer *layer, const QString &path, QgsProcessingContext &context,
-    QgsProcessingFeedback *feedback )
+    QgsProcessingFeedback *feedback, bool saveStyles )
 {
   QgsVectorFileWriter::SaveVectorOptions options;
   options.driverName = QStringLiteral( "GPKG" );
@@ -172,13 +175,54 @@ bool QgsPackageAlgorithm::packageVectorLayer( QgsVectorLayer *layer, const QStri
   options.feedback = feedback;
 
   QString error;
-  if ( QgsVectorFileWriter::writeAsVectorFormat( layer, path, options, nullptr, &error ) != QgsVectorFileWriter::NoError )
+  QString newFilename;
+  QString newLayer;
+  if ( QgsVectorFileWriter::writeAsVectorFormat( layer, path, options, &newFilename, &error, &newLayer ) != QgsVectorFileWriter::NoError )
   {
     feedback->reportError( QObject::tr( "Packaging layer failed: %1" ).arg( error ) );
     return false;
   }
   else
   {
+    if ( saveStyles )
+    {
+      std::unique_ptr< QgsVectorLayer > res = qgis::make_unique< QgsVectorLayer >( QStringLiteral( "%1|layername=%2" ).arg( newFilename, newLayer ) );
+      if ( res )
+      {
+        QString errorMsg;
+        QDomDocument doc( QStringLiteral( "qgis" ) );
+        QgsReadWriteContext context;
+        layer->exportNamedStyle( doc, errorMsg, context );
+        if ( !errorMsg.isEmpty() )
+        {
+          feedback->reportError( QObject::tr( "Could not retrieve existing layer style: %1 " ).arg( errorMsg ) );
+        }
+        else
+        {
+          if ( !res->importNamedStyle( doc, errorMsg ) )
+          {
+            feedback->reportError( QObject::tr( "Could not set existing layer style: %1 " ).arg( errorMsg ) );
+          }
+          else
+          {
+            QgsSettings settings;
+            // this is not nice -- but needed to avoid an "overwrite" prompt messagebox from the provider! This api needs a rework to avoid this.
+            QVariant prevOverwriteStyle = settings.value( QStringLiteral( "qgis/overwriteStyle" ) );
+            settings.setValue( QStringLiteral( "qgis/overwriteStyle" ), true );
+            res->saveStyleToDatabase( newLayer, QString(), true, QString(), errorMsg );
+            settings.setValue( QStringLiteral( "qgis/overwriteStyle" ), prevOverwriteStyle );
+            if ( !errorMsg.isEmpty() )
+            {
+              feedback->reportError( QObject::tr( "Could not save layer style: %1 " ).arg( errorMsg ) );
+            }
+          }
+        }
+      }
+      else
+      {
+        feedback->reportError( QObject::tr( "Could not save layer style -- error loading: %1 %2" ).arg( newFilename, newLayer ) );
+      }
+    }
     return true;
   }
 }

diff --git a/src/analysis/processing/qgsalgorithmpackage.h b/src/analysis/processing/qgsalgorithmpackage.h
@@ -52,7 +52,7 @@ class QgsPackageAlgorithm : public QgsProcessingAlgorithm
 
   private:
 
-    bool packageVectorLayer( QgsVectorLayer *layer, const QString &path, QgsProcessingContext &context, QgsProcessingFeedback *feedback );
+    bool packageVectorLayer( QgsVectorLayer *layer, const QString &path, QgsProcessingContext &context, QgsProcessingFeedback *feedback, bool saveStyles );
 
 };