[FEATURE]: Transactional editing for postgres layers (other datasourc…

…es possible in the future). Funded by City of Uster
qgis · Jan 19, 2015 · 40ad3b0 · m-kuhn · Dec 1, 2015 · manisandro
1 parent 7e3bef6
commit 40ad3b0
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Showing 23 changed files with 1,052 additions and 185 deletions.
diff --git a/python/core/core.sip b/python/core/core.sip
@@ -12,6 +12,7 @@
 
 %Include qgis.sip
 
+%Include qgstransaction.sip
 %Include qgsapplication.sip
 %Include qgsattributeaction.sip
 %Include qgsbrowsermodel.sip

diff --git a/python/core/qgstransaction.sip b/python/core/qgstransaction.sip
@@ -0,0 +1,51 @@
+/**
+ * This class allows to include a set of layers in a database-side transaction,
+ * provided the layer data providers support transactions and are compatible
+ * with each other.
+ *
+ * Only layers which are not in edit mode can be included in a transaction,
+ * and all layers need to be in read-only mode for a transaction to be committed
+ * or rolled back.
+ *
+ * Layers cannot only be included in one transaction at a time.
+ *
+ * When editing layers which are part of a transaction group, all changes are
+ * sent directly to the data provider (bypassing the undo/redo stack), and the
+ * changes can either be committed or rolled back on the database side via the
+ * QgsTransaction::commit and QgsTransaction::rollback methods.
+ *
+ * As long as the transaction is active, the state of all layer features reflects
+ * the current state in the transaction.
+ *
+ * Edits on features can get rejected if another conflicting transaction is active.
+ */
+class QgsTransaction /Abstract/
+{
+%TypeHeaderCode
+#include <qgstransaction.h>
+%End
+  public:
+    /** Creates a transaction for the specified connection string and provider */
+    static QgsTransaction* create( const QString& connString, const QString& providerKey ) /Factory/;
+
+    /** Creates a transaction which includes the specified layers. Connection string
+     *  and data provider are taken from the first layer */
+    static QgsTransaction* create( const QStringList& layerIds ) /Factory/;
+
+    virtual ~QgsTransaction();
+
+	/** Add layer to the transaction. The layer must not be in edit mode. The transaction must not be active. */
+    bool addLayer( const QString& layerId );
+
+    /** Begin transaction */
+    bool begin( QString& errorMsg );
+
+    /** Commit transaction. All layers need to be in read-only mode. */
+    bool commit( QString& errorMsg );
+
+    /** Roll back transaction. All layers need to be in read-only mode. */
+    bool rollback( QString& errorMsg );
+
+    /** Executes sql */
+    virtual bool executeSql( const QString& sql, QString& error ) = 0;
+};
diff --git a/python/core/qgsvectordataprovider.sip b/python/core/qgsvectordataprovider.sip
@@ -313,6 +313,8 @@ class QgsVectorDataProvider : QgsDataProvider
 
     static QVariant convertValue( QVariant::Type type, QString value );
 
+    virtual QgsTransaction* transaction() const;
+
   protected:
     void clearMinMaxCache();
     void fillMinMaxCache();

diff --git a/src/core/CMakeLists.txt b/src/core/CMakeLists.txt
@@ -153,12 +153,14 @@ SET(QGIS_CORE_SRCS
   qgssimplifymethod.cpp
   qgssnapper.cpp
   qgsspatialindex.cpp
+  qgstransaction.cpp
   qgstolerance.cpp
   qgsvectordataprovider.cpp
   qgsvectorfilewriter.cpp
   qgsvectorlayer.cpp
   qgsvectorlayercache.cpp
   qgsvectorlayereditbuffer.cpp
+  qgsvectorlayereditpassthrough.cpp
   qgsvectorlayereditutils.cpp
   qgsvectorlayerfeatureiterator.cpp
   qgsvectorlayerimport.cpp
@@ -188,7 +190,7 @@ SET(QGIS_CORE_SRCS
   composer/qgscomposermapoverview.cpp
   composer/qgscomposertable.cpp
   composer/qgscomposertablev2.cpp
-  composer/qgscomposertablecolumn.cpp  
+  composer/qgscomposertablecolumn.cpp
   composer/qgscomposerattributetable.cpp
   composer/qgscomposerattributetablev2.cpp
   composer/qgscomposerattributetablemodel.cpp
@@ -211,7 +213,7 @@ SET(QGIS_CORE_SRCS
   composer/qgscomposermultiframe.cpp
   composer/qgscomposermodel.cpp
   composer/qgscomposition.cpp
-  
+
   dxf/qgsdxfexport.cpp
   dxf/qgsdxfpaintdevice.cpp
   dxf/qgsdxfpaintengine.cpp
@@ -269,7 +271,7 @@ SET(QGIS_CORE_SRCS
   raster/qgssinglebandgrayrenderer.cpp
   raster/qgssinglebandpseudocolorrenderer.cpp
   raster/qgsbrightnesscontrastfilter.cpp
-  raster/qgshuesaturationfilter.cpp  
+  raster/qgshuesaturationfilter.cpp
 )
 
 IF(ENABLE_MODELTEST)
@@ -360,6 +362,7 @@ SET(QGIS_CORE_MOC_HDRS
   qgsrunprocess.h
   qgsrelationmanager.h
   qgsvectorlayer.h
+  qgsvectorlayereditpassthrough.h
   qgsvectorlayereditbuffer.h
   qgsnetworkaccessmanager.h
   qgsvectordataprovider.h
@@ -378,14 +381,14 @@ SET(QGIS_CORE_MOC_HDRS
   composer/qgscomposerobject.h
   composer/qgscomposeritem.h
   composer/qgscomposeritemgroup.h
-  composer/qgscomposermousehandles.h  
+  composer/qgscomposermousehandles.h
   composer/qgscomposerlabel.h
   composer/qgscomposershape.h
   composer/qgscomposerattributetable.h
   composer/qgscomposerattributetablev2.h
   composer/qgscomposerattributetablemodel.h
-  composer/qgscomposerattributetablemodelv2.h    
-  composer/qgscomposertable.h  
+  composer/qgscomposerattributetablemodelv2.h
+  composer/qgscomposertable.h
   composer/qgscomposertablev2.h
   composer/qgscomposertablecolumn.h
   composer/qgscomposerhtml.h
@@ -459,6 +462,8 @@ SET(QGIS_CORE_HDRS
   qgsclipper.h
   qgscolorscheme.h
   qgscolorschemeregistry.h
+  qgsconnectionpool.h
+  qgscontexthelp.h
   qgscoordinatereferencesystem.h
   qgscrscache.h
   qgscsexception.h
@@ -526,6 +531,9 @@ SET(QGIS_CORE_HDRS
   qgssnapper.h
   qgsspatialindex.h
   qgstolerance.h
+  qgstransaction.h
+  qgsvectordataprovider.h
+  qgsvectorlayercache.h
   qgsvectorfilewriter.h
   qgsvectorlayereditutils.h
   qgsvectorlayerfeatureiterator.h

diff --git a/src/core/qgstransaction.cpp b/src/core/qgstransaction.cpp
@@ -0,0 +1,213 @@
+/***************************************************************************
+                              qgstransaction.cpp
+                              ------------------
+  begin                : May 5, 2014
+  copyright            : (C) 2014 by Marco Hugentobler
+  email                : marco dot hugentobler at sourcepole dot ch
+ ***************************************************************************/
+
+/***************************************************************************
+ *                                                                         *
+ *   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 <QLibrary>
+
+#include "qgstransaction.h"
+#include "qgsdatasourceuri.h"
+#include "qgsmaplayerregistry.h"
+#include "qgsproviderregistry.h"
+#include "qgsvectordataprovider.h"
+#include "qgsvectorlayer.h"
+
+typedef QgsTransaction* createTransaction_t( const QString& connString );
+
+QgsTransaction* QgsTransaction::create( const QString& connString, const QString& providerKey )
+{
+
+  QLibrary* lib = QgsProviderRegistry::instance()->providerLibrary( providerKey );
+  if ( !lib )
+  {
+    return 0;
+  }
+
+  createTransaction_t* createTransaction = ( createTransaction_t* ) cast_to_fptr( lib->resolve( "createTransaction" ) );
+  if ( !createTransaction )
+  {
+    return 0;
+  }
+
+  QgsTransaction* ts = createTransaction( connString );
+
+  delete lib;
+
+  return ts;
+}
+
+QgsTransaction* QgsTransaction::create( const QStringList& layerIds )
+{
+  if ( layerIds.isEmpty() )
+  {
+    return 0;
+  }
+
+  QgsVectorLayer* layer = qobject_cast<QgsVectorLayer*>( QgsMapLayerRegistry::instance()->mapLayer( layerIds.first() ) );
+  if ( !layer )
+  {
+    return 0;
+  }
+
+  QString connStr = QgsDataSourceURI( layer->source() ).connectionInfo();
+  QString providerKey = layer->dataProvider()->name();
+  QgsTransaction* ts = QgsTransaction::create( connStr, providerKey );
+  if ( !ts )
+  {
+    return 0;
+  }
+
+  foreach ( const QString& layerId, layerIds )
+  {
+    if ( !ts->addLayer( layerId ) )
+    {
+      delete ts;
+      return 0;
+    }
+  }
+  return ts;
+}
+
+
+QgsTransaction::QgsTransaction( const QString& connString )
+    : mConnString( connString ), mTransactionActive( false )
+{
+}
+
+QgsTransaction::~QgsTransaction()
+{
+  setLayerTransactionIds( 0 );
+}
+
+bool QgsTransaction::addLayer( const QString& layerId )
+{
+  if ( mTransactionActive )
+  {
+    return false;
+  }
+
+  QgsVectorLayer* layer = qobject_cast<QgsVectorLayer*>( QgsMapLayerRegistry::instance()->mapLayer( layerId ) );
+  if ( !layer )
+  {
+    return false;
+  }
+
+  if ( layer->isEditable() )
+  {
+    return false;
+  }
+
+  //test if provider supports transactions
+  if ( !layer->dataProvider() || !layer->dataProvider()->capabilities() & QgsVectorDataProvider::TransactionSupport )
+  {
+    return false;
+  }
+
+  if ( layer->dataProvider()->transaction() != 0 )
+  {
+    return false;
+  }
+
+  //connection string not compatible
+  if ( QgsDataSourceURI( layer->source() ).connectionInfo() != mConnString )
+  {
+    return false;
+  }
+
+  mLayers.insert( layerId );
+  return true;
+}
+
+bool QgsTransaction::begin( QString& errorMsg, int statementTimeout )
+{
+  if ( mTransactionActive )
+  {
+    return false;
+  }
+
+  //Set all layers to direct edit mode
+  if ( !beginTransaction( errorMsg, statementTimeout ) )
+  {
+    return false;
+  }
+
+  setLayerTransactionIds( this );
+  mTransactionActive = true;
+  return true;
+}
+
+bool QgsTransaction::commit( QString& errorMsg )
+{
+  if ( !mTransactionActive )
+  {
+    return false;
+  }
+
+  foreach ( const QString& layerid, mLayers )
+  {
+    QgsMapLayer* l = QgsMapLayerRegistry::instance()->mapLayer( layerid );
+    if ( !l || l->isEditable() )
+    {
+      return false;
+    }
+  }
+
+  if ( !commitTransaction( errorMsg ) )
+  {
+    return false;
+  }
+
+  setLayerTransactionIds( 0 );
+  mTransactionActive = false;
+  return true;
+}
+
+bool QgsTransaction::rollback( QString& errorMsg )
+{
+  if ( !mTransactionActive )
+  {
+    return false;
+  }
+
+  foreach ( const QString& layerid, mLayers )
+  {
+    QgsMapLayer* l = QgsMapLayerRegistry::instance()->mapLayer( layerid );
+    if ( !l || l->isEditable() )
+    {
+      return false;
+    }
+  }
+
+  if ( !rollbackTransaction( errorMsg ) )
+  {
+    return false;
+  }
+
+  setLayerTransactionIds( 0 );
+  mTransactionActive = false;
+  return true;
+}
+
+void QgsTransaction::setLayerTransactionIds( QgsTransaction* transaction )
+{
+  foreach ( const QString& layerid, mLayers )
+  {
+    QgsVectorLayer* vl = qobject_cast<QgsVectorLayer*>( QgsMapLayerRegistry::instance()->mapLayer( layerid ) );
+    if ( vl && vl->dataProvider() )
+    {
+      vl->dataProvider()->setTransaction( transaction );
+    }
+  }
+}