Tidy up layer definitions code + removal of QgsProject::instance()

Moved code related to layer definitions away from QgsMapLayer

doc/api_break.dox

@@ -1181,6 +1181,12 @@ QgsLabelingEngineInterface        {#qgis_api_break_3_0_QgsLabelingEngineInterfac
 - labelsWithinRect() was removed. Use takeResults() and methods of QgsLabelingResults.
 
 
+QgsLayerDefinition        {#qgis_api_break_3_0_QgsLayerDefinition}
+------------------
+
+- loadLayerDefinition() now also requires QgsProject as the second argument
+
+
 QgsLayerPropertiesWidget        {#qgis_api_break_3_0_QgsLayerPropertiesWidget}
 ------------------------
 
@@ -1298,6 +1304,7 @@ screenUpdateRequested() were removed. These members have had no effect for a num
 - readLayerXML() was renamed to readLayerXml()
 - writeLayerXML() was renamed to writeLayerXml()
 - capitaliseLayerName() was renamed to capitalizeLayerName() <!--#spellok-->
+- asLayerDefinition(), fromLayerDefinition(), fromLayerDefinitionFile() were moved to QgsLayerDefinition class and renamed to exportLayerDefinitionLayers() resp. loadLayerDefinitionLayers()
 
 
 QgsMapLayerRegistry        {#qgis_api_break_3_0_QgsMapLayerRegistry}

python/core/qgslayerdefinition.sip

@@ -11,15 +11,15 @@ class QgsLayerDefinition
 #include <qgslayerdefinition.h>
 %End
   public:
-    /** Loads the QLR at path into QGIS.  New layers are added to rootGroup and the map layer registry*/
-    static bool loadLayerDefinition( const QString & path, QgsLayerTreeGroup* rootGroup, QString &errorMessage /Out/ );
-    /** Loads the QLR from the XML document.  New layers are added to rootGroup and the map layer registry */
-    static bool loadLayerDefinition( QDomDocument doc, QgsLayerTreeGroup* rootGroup, QString &errorMessage /Out/ );
-    /** Export the selected layer tree nodes to a QLR file */
+    static bool loadLayerDefinition( const QString & path, QgsProject* project, QgsLayerTreeGroup* rootGroup, QString &errorMessage /Out/ );
+    static bool loadLayerDefinition( QDomDocument doc, QgsProject* project, QgsLayerTreeGroup* rootGroup, QString &errorMessage /Out/ );
     static bool exportLayerDefinition( QString path, const QList<QgsLayerTreeNode*>& selectedTreeNodes, QString &errorMessage /Out/ );
-    /** Export the selected layer tree nodes to a QLR-XML document */
     static bool exportLayerDefinition( QDomDocument doc, const QList<QgsLayerTreeNode*>& selectedTreeNodes, QString &errorMessage, const QString& relativeBasePath = QString::null );
 
+    static QDomDocument exportLayerDefinitionLayers( const QList<QgsMapLayer*>& layers, const QString& relativeBasePath = QString::null );
+    static QList<QgsMapLayer*> loadLayerDefinitionLayers( QDomDocument& document ) /Factory/;
+    static QList<QgsMapLayer*> loadLayerDefinitionLayers( const QString &qlrfile ) /Factory/;
+
     /**
      * Class used to work with layer dependencies stored in a XML project or layer definition file
      */

python/core/qgsmaplayer.sip

@@ -355,18 +355,6 @@ class QgsMapLayer : QObject
      */
     bool writeLayerXml( QDomElement& layerElement, QDomDocument& document, const QString& relativeBasePath = QString::null ) const;
 
-    /** Returns the given layer as a layer definition document
-     *  Layer definitions store the data source as well as styling and custom properties.
-     *
-     *  Layer definitions can be used to load a layer and styling all from a single file.
-     */
-    static QDomDocument asLayerDefinition( const QList<QgsMapLayer*>& layers, const QString& relativeBasePath = QString::null );
-
-    /** Creates a new layer from a layer definition document
-     */
-    static QList<QgsMapLayer*> fromLayerDefinition( QDomDocument& document, bool addToRegistry = false, bool addToLegend = false );
-    static QList<QgsMapLayer*> fromLayerDefinitionFile( const QString &qlrfile );
-
     /** Set a custom property for layer. Properties are stored in a map and saved in project file.
      * @see customProperty()
      * @see removeCustomProperty()

src/app/qgisapp.cpp

@@ -5249,7 +5249,7 @@ void QgisApp::dwgImport()
 void QgisApp::openLayerDefinition( const QString & path )
 {
   QString errorMessage;
-  bool loaded = QgsLayerDefinition::loadLayerDefinition( path, QgsProject::instance()->layerTreeRoot(), errorMessage );
+  bool loaded = QgsLayerDefinition::loadLayerDefinition( path, QgsProject::instance(), QgsProject::instance()->layerTreeRoot(), errorMessage );
   if ( !loaded )
   {
     QgsDebugMsg( errorMessage );

src/core/qgslayerdefinition.cpp

@@ -18,14 +18,17 @@
 #include <QDir>
 #include <QTextStream>
 
+#include "qgslayerdefinition.h"
+#include "qgslayertree.h"
 #include "qgslogger.h"
 #include "qgsmaplayer.h"
-#include "qgsvectorlayer.h"
-#include "qgslayertree.h"
-#include "qgslayerdefinition.h"
+#include "qgspluginlayer.h"
+#include "qgspluginlayerregistry.h"
 #include "qgsproject.h"
+#include "qgsrasterlayer.h"
+#include "qgsvectorlayer.h"
 
-bool QgsLayerDefinition::loadLayerDefinition( const QString &path, QgsLayerTreeGroup *rootGroup, QString &errorMessage )
+bool QgsLayerDefinition::loadLayerDefinition( const QString &path, QgsProject* project, QgsLayerTreeGroup *rootGroup, QString &errorMessage )
 {
   QFile file( path );
   if ( !file.open( QIODevice::ReadOnly ) )
@@ -45,10 +48,10 @@ bool QgsLayerDefinition::loadLayerDefinition( const QString &path, QgsLayerTreeG
   QFileInfo fileinfo( file );
   QDir::setCurrent( fileinfo.absoluteDir().path() );
 
-  return loadLayerDefinition( doc, rootGroup, errorMessage );
+  return loadLayerDefinition( doc, project, rootGroup, errorMessage );
 }
 
-bool QgsLayerDefinition::loadLayerDefinition( QDomDocument doc, QgsLayerTreeGroup *rootGroup, QString &errorMessage )
+bool QgsLayerDefinition::loadLayerDefinition( QDomDocument doc, QgsProject* project, QgsLayerTreeGroup *rootGroup, QString &errorMessage )
 {
   Q_UNUSED( errorMessage );
 
@@ -137,7 +140,9 @@ bool QgsLayerDefinition::loadLayerDefinition( QDomDocument doc, QgsLayerTreeGrou
     loadInLegend = false;
   }
 
-  QList<QgsMapLayer*> layers = QgsMapLayer::fromLayerDefinition( doc, /*addToRegistry*/ true, loadInLegend );
+  QList<QgsMapLayer*> layers = QgsLayerDefinition::loadLayerDefinitionLayers( doc );
+
+  project->addMapLayers( layers, loadInLegend );
 
   // Now that all layers are loaded, refresh the vectorjoins to get the joined fields
   Q_FOREACH ( QgsMapLayer* layer, layers )
@@ -150,7 +155,7 @@ bool QgsLayerDefinition::loadLayerDefinition( QDomDocument doc, QgsLayerTreeGrou
     }
   }
 
-  root->resolveReferences( QgsProject::instance() );
+  root->resolveReferences( project );
 
   QList<QgsLayerTreeNode*> nodes = root->children();
   Q_FOREACH ( QgsLayerTreeNode *node, nodes )
@@ -213,6 +218,82 @@ bool QgsLayerDefinition::exportLayerDefinition( QDomDocument doc, const QList<Qg
   return true;
 }
 
+QDomDocument QgsLayerDefinition::exportLayerDefinitionLayers( const QList<QgsMapLayer *>& layers, const QString& relativeBasePath )
+{
+  QDomDocument doc( QStringLiteral( "qgis-layer-definition" ) );
+  QDomElement qgiselm = doc.createElement( QStringLiteral( "qlr" ) );
+  doc.appendChild( qgiselm );
+  QDomElement layerselm = doc.createElement( QStringLiteral( "maplayers" ) );
+  Q_FOREACH ( QgsMapLayer* layer, layers )
+  {
+    QDomElement layerelm = doc.createElement( QStringLiteral( "maplayer" ) );
+    layer->writeLayerXml( layerelm, doc, relativeBasePath );
+    layerselm.appendChild( layerelm );
+  }
+  qgiselm.appendChild( layerselm );
+  return doc;
+}
+
+QList<QgsMapLayer*> QgsLayerDefinition::loadLayerDefinitionLayers( QDomDocument& document )
+{
+  QList<QgsMapLayer*> layers;
+  QDomNodeList layernodes = document.elementsByTagName( QStringLiteral( "maplayer" ) );
+  for ( int i = 0; i < layernodes.size(); ++i )
+  {
+    QDomNode layernode = layernodes.at( i );
+    QDomElement layerElem = layernode.toElement();
+
+    QString type = layerElem.attribute( QStringLiteral( "type" ) );
+    QgsDebugMsg( type );
+    QgsMapLayer *layer = nullptr;
+
+    if ( type == QLatin1String( "vector" ) )
+    {
+      layer = new QgsVectorLayer;
+    }
+    else if ( type == QLatin1String( "raster" ) )
+    {
+      layer = new QgsRasterLayer;
+    }
+    else if ( type == QLatin1String( "plugin" ) )
+    {
+      QString typeName = layerElem.attribute( QStringLiteral( "name" ) );
+      layer = QgsApplication::pluginLayerRegistry()->createLayer( typeName );
+    }
+
+    if ( !layer )
+      continue;
+
+    if ( layer->readLayerXml( layerElem ) )
+    {
+      layers << layer;
+    }
+  }
+  return layers;
+}
+
+QList<QgsMapLayer *> QgsLayerDefinition::loadLayerDefinitionLayers( const QString &qlrfile )
+{
+  QFile file( qlrfile );
+  if ( !file.open( QIODevice::ReadOnly ) )
+  {
+    QgsDebugMsg( "Can't open file" );
+    return QList<QgsMapLayer*>();
+  }
+
+  QDomDocument doc;
+  if ( !doc.setContent( &file ) )
+  {
+    QgsDebugMsg( "Can't set content" );
+    return QList<QgsMapLayer*>();
+  }
+
+  QFileInfo fileinfo( file );
+  QDir::setCurrent( fileinfo.absoluteDir().path() );
+  return QgsLayerDefinition::loadLayerDefinitionLayers( doc );
+}
+
+
 void QgsLayerDefinition::DependencySorter::init( const QDomDocument& doc )
 {
   // Determine a loading order of layers based on a graph of dependencies

src/core/qgslayerdefinition.h

@@ -17,10 +17,17 @@
 
 
 #include "qgis_core.h"
+
 #include <QString>
+#include <QVector>
+
+class QDomNode;
+class QDomDocument;
 
 class QgsLayerTreeGroup;
 class QgsLayerTreeNode;
+class QgsMapLayer;
+class QgsProject;
 
 /** \ingroup core
  * @brief The QgsLayerDefinition class holds generic methods for loading/exporting QLR files.
@@ -32,15 +39,34 @@ class QgsLayerTreeNode;
 class CORE_EXPORT QgsLayerDefinition
 {
   public:
-    //! Loads the QLR at path into QGIS.  New layers are added to rootGroup and the map layer registry
-    static bool loadLayerDefinition( const QString & path, QgsLayerTreeGroup* rootGroup, QString &errorMessage );
-    //! Loads the QLR from the XML document.  New layers are added to rootGroup and the map layer registry
-    static bool loadLayerDefinition( QDomDocument doc, QgsLayerTreeGroup* rootGroup, QString &errorMessage );
+    //! Loads the QLR at path into QGIS.  New layers are added to given project into layer tree specified by rootGroup
+    static bool loadLayerDefinition( const QString & path, QgsProject* project, QgsLayerTreeGroup* rootGroup, QString &errorMessage );
+    //! Loads the QLR from the XML document.  New layers are added to given project into layer tree specified by rootGroup
+    static bool loadLayerDefinition( QDomDocument doc, QgsProject* project, QgsLayerTreeGroup* rootGroup, QString &errorMessage );
     //! Export the selected layer tree nodes to a QLR file
     static bool exportLayerDefinition( QString path, const QList<QgsLayerTreeNode*>& selectedTreeNodes, QString &errorMessage );
     //! Export the selected layer tree nodes to a QLR-XML document
     static bool exportLayerDefinition( QDomDocument doc, const QList<QgsLayerTreeNode*>& selectedTreeNodes, QString &errorMessage, const QString& relativeBasePath = QString::null );
 
+    /** Returns the given layer as a layer definition document
+     *  Layer definitions store the data source as well as styling and custom properties.
+     *
+     *  Layer definitions can be used to load a layer and styling all from a single file.
+     *
+     *  This is a low-level routine that does not write layer tree.
+     *  @see exportLayerDefinition()
+     */
+    static QDomDocument exportLayerDefinitionLayers( const QList<QgsMapLayer*>& layers, const QString& relativeBasePath = QString::null );
+
+    //! Creates new layers from a layer definition document.
+    //! This is a low-level routine that does not resolve layer ID conflicts, dependencies and joins
+    //! @see loadLayerDefinition()
+    static QList<QgsMapLayer*> loadLayerDefinitionLayers( QDomDocument& document );
+    //! Creates new layers from a layer definition file (.QLR)
+    //! This is a low-level routine that does not resolve layer ID conflicts, dependencies and joins
+    //! @see loadLayerDefinition()
+    static QList<QgsMapLayer*> loadLayerDefinitionLayers( const QString &qlrfile );
+
     /**
      * \ingroup core
      * Class used to work with layer dependencies stored in a XML project or layer definition file

src/core/qgsmaplayer.cpp

@@ -38,8 +38,6 @@
 #include "qgsmaplayer.h"
 #include "qgsmaplayerlegend.h"
 #include "qgsmaplayerstylemanager.h"
-#include "qgspluginlayer.h"
-#include "qgspluginlayerregistry.h"
 #include "qgsprojectfiletransform.h"
 #include "qgsproject.h"
 #include "qgsproviderregistry.h"
@@ -783,84 +781,6 @@ bool QgsMapLayer::writeLayerXml( QDomElement& layerElement, QDomDocument& docume
 
 } // bool QgsMapLayer::writeXml
 
-QDomDocument QgsMapLayer::asLayerDefinition( const QList<QgsMapLayer *>& layers, const QString& relativeBasePath )
-{
-  QDomDocument doc( QStringLiteral( "qgis-layer-definition" ) );
-  QDomElement qgiselm = doc.createElement( QStringLiteral( "qlr" ) );
-  doc.appendChild( qgiselm );
-  QDomElement layerselm = doc.createElement( QStringLiteral( "maplayers" ) );
-  Q_FOREACH ( QgsMapLayer* layer, layers )
-  {
-    QDomElement layerelm = doc.createElement( QStringLiteral( "maplayer" ) );
-    layer->writeLayerXml( layerelm, doc, relativeBasePath );
-    layerselm.appendChild( layerelm );
-  }
-  qgiselm.appendChild( layerselm );
-  return doc;
-}
-
-QList<QgsMapLayer*> QgsMapLayer::fromLayerDefinition( QDomDocument& document, bool addToRegistry, bool addToLegend )
-{
-  QList<QgsMapLayer*> layers;
-  QDomNodeList layernodes = document.elementsByTagName( QStringLiteral( "maplayer" ) );
-  for ( int i = 0; i < layernodes.size(); ++i )
-  {
-    QDomNode layernode = layernodes.at( i );
-    QDomElement layerElem = layernode.toElement();
-
-    QString type = layerElem.attribute( QStringLiteral( "type" ) );
-    QgsDebugMsg( type );
-    QgsMapLayer *layer = nullptr;
-
-    if ( type == QLatin1String( "vector" ) )
-    {
-      layer = new QgsVectorLayer;
-    }
-    else if ( type == QLatin1String( "raster" ) )
-    {
-      layer = new QgsRasterLayer;
-    }
-    else if ( type == QLatin1String( "plugin" ) )
-    {
-      QString typeName = layerElem.attribute( QStringLiteral( "name" ) );
-      layer = QgsApplication::pluginLayerRegistry()->createLayer( typeName );
-    }
-
-    if ( !layer )
-      continue;
-
-    bool ok = layer->readLayerXml( layerElem );
-    if ( ok )
-    {
-      layers << layer;
-      if ( addToRegistry )
-        QgsProject::instance()->addMapLayer( layer, addToLegend );
-    }
-  }
-  return layers;
-}
-
-QList<QgsMapLayer *> QgsMapLayer::fromLayerDefinitionFile( const QString &qlrfile )
-{
-  QFile file( qlrfile );
-  if ( !file.open( QIODevice::ReadOnly ) )
-  {
-    QgsDebugMsg( "Can't open file" );
-    return QList<QgsMapLayer*>();
-  }
-
-  QDomDocument doc;
-  if ( !doc.setContent( &file ) )
-  {
-    QgsDebugMsg( "Can't set content" );
-    return QList<QgsMapLayer*>();
-  }
-
-  QFileInfo fileinfo( file );
-  QDir::setCurrent( fileinfo.absoluteDir().path() );
-  return QgsMapLayer::fromLayerDefinition( doc );
-}
-
 
 bool QgsMapLayer::writeXml( QDomNode & layer_node, QDomDocument & document ) const
 {

src/core/qgsmaplayer.h

@@ -383,18 +383,6 @@ class CORE_EXPORT QgsMapLayer : public QObject
      */
     bool writeLayerXml( QDomElement& layerElement, QDomDocument& document, const QString& relativeBasePath = QString::null ) const;
 
-    /** Returns the given layer as a layer definition document
-     *  Layer definitions store the data source as well as styling and custom properties.
-     *
-     *  Layer definitions can be used to load a layer and styling all from a single file.
-     */
-    static QDomDocument asLayerDefinition( const QList<QgsMapLayer*>& layers, const QString& relativeBasePath = QString::null );
-
-    /** Creates a new layer from a layer definition document
-     */
-    static QList<QgsMapLayer*> fromLayerDefinition( QDomDocument& document, bool addToRegistry = false, bool addToLegend = false );
-    static QList<QgsMapLayer*> fromLayerDefinitionFile( const QString &qlrfile );
-
     /** Set a custom property for layer. Properties are stored in a map and saved in project file.
      * @see customProperty()
      * @see removeCustomProperty()

tests/src/core/testqgsvectorlayerjoinbuffer.cpp

@@ -505,7 +505,7 @@ void TestVectorLayerJoinBuffer::testJoinLayerDefinitionFile()
   QgsProject::instance()->removeAllMapLayers();
 
   // Load QLR
-  r = QgsLayerDefinition::loadLayerDefinition( qlrDoc, QgsProject::instance()->layerTreeRoot(), errorMessage );
+  r = QgsLayerDefinition::loadLayerDefinition( qlrDoc, QgsProject::instance(), QgsProject::instance()->layerTreeRoot(), errorMessage );
   QVERIFY2( r, errorMessage.toUtf8().constData() );
 
   // Get layer

tests/src/python/test_layer_dependencies.py

@@ -196,7 +196,7 @@ class TestLayerDependencies(unittest.TestCase):
         QgsLayerDefinition.exportLayerDefinition(tmpfile, [ltr])
 
         grp = ltr.addGroup("imported")
-        QgsLayerDefinition.loadLayerDefinition(tmpfile, grp)
+        QgsLayerDefinition.loadLayerDefinition(tmpfile, QgsProject.instance(), grp)
 
         newPointsLayer = None
         newLinesLayer = None

tests/src/python/test_provider_memory.py

@@ -16,6 +16,7 @@ __revision__ = '$Format:%H$'
 from qgis.core import (
     Qgis,
     QgsField,
+    QgsLayerDefinition,
     QgsPoint,
     QgsMapLayer,
     QgsVectorLayer,
@@ -282,11 +283,11 @@ class TestPyQgsMemoryProvider(unittest.TestCase, ProviderTestCase):
         myMemoryLayer.updateFields()
 
         # Export the layer to a layer-definition-XML
-        qlr = QgsMapLayer.asLayerDefinition([myMemoryLayer])
+        qlr = QgsLayerDefinition.exportLayerDefinitionLayers([myMemoryLayer])
         assert qlr is not None
 
         # Import the layer from the layer-definition-XML
-        layers = QgsMapLayer.fromLayerDefinition(qlr)
+        layers = QgsLayerDefinition.loadLayerDefinitionLayers(qlr)
         assert layers is not None
         myImportedLayer = layers[0]
         assert myImportedLayer is not None

tests/src/python/test_qgslayerdefinition.py

@@ -103,7 +103,7 @@ class TestQgsLayerDefinition(unittest.TestCase):
         layers = QgsProject.instance().mapLayers()
         self.assertEqual(len(layers), 0)
 
-        (result, errMsg) = QgsLayerDefinition.loadLayerDefinition(TEST_DATA_DIR + '/vector_and_raster.qlr', QgsProject.instance().layerTreeRoot())
+        (result, errMsg) = QgsLayerDefinition.loadLayerDefinition(TEST_DATA_DIR + '/vector_and_raster.qlr', QgsProject.instance(), QgsProject.instance().layerTreeRoot())
         self.assertTrue(result)
 
         layers = QgsProject.instance().mapLayers()