raster creation moved from QgsGdalProvider::create() to GDAL provider extern C function

python/core/raster/qgsrasterdataprovider.sip

@@ -249,7 +249,9 @@ class QgsRasterDataProvider : QgsDataProvider, QgsRasterInterface
 
     /** Creates a new dataset with mDataSourceURI
         @return true in case of success*/
-    virtual bool create( const QString& format, int nBands,
+    static QgsRasterDataProvider* create( const QString &providerKey,
+                         const QString &uri,
+                         const QString& format, int nBands,
                          QGis::DataType type,
                          int width, int height, double* geoTransform,
                          const QgsCoordinateReferenceSystem& crs,

src/core/raster/qgsrasterdataprovider.cpp

@@ -15,6 +15,7 @@
  *                                                                         *
  ***************************************************************************/
 
+#include "qgsproviderregistry.h"
 #include "qgsrasterdataprovider.h"
 #include "qgsrasterprojector.h"
 #include "qgslogger.h"
@@ -475,4 +476,30 @@ void QgsRasterDataProvider::setUserNoDataValue( int bandNo, QList<QgsRasterBlock
   }
 }
 
+typedef QgsRasterDataProvider * createFunction_t( const QString&,
+    const QString&, int,
+    QGis::DataType,
+    int, int, double*,
+    const QgsCoordinateReferenceSystem&,
+    QStringList );
+
+QgsRasterDataProvider* QgsRasterDataProvider::create( const QString &providerKey,
+    const QString &uri,
+    const QString& format, int nBands,
+    QGis::DataType type,
+    int width, int height, double* geoTransform,
+    const QgsCoordinateReferenceSystem& crs,
+    QStringList createOptions )
+{
+  createFunction_t *createFn = ( createFunction_t* ) cast_to_fptr( QgsProviderRegistry::instance()->function( providerKey, "create" ) );
+  if ( !createFn )
+  {
+    QgsDebugMsg( "Cannot resolve 'create' function in " + providerKey + " provider" );
+    // TODO: it would be good to return invalid QgsRasterDataProvider
+    // with QgsError set, but QgsRasterDataProvider has pure virtual methods
+    return 0;
+  }
+  return createFn( uri, format, nBands, type, width, height, geoTransform, crs, createOptions );
+}
+
 // ENDS

src/core/raster/qgsrasterdataprovider.h

@@ -403,6 +403,7 @@ class CORE_EXPORT QgsRasterDataProvider : public QgsDataProvider, public QgsRast
 
     /** Creates a new dataset with mDataSourceURI
         @return true in case of success*/
+#if 0
     virtual bool create( const QString& format, int nBands,
                          QGis::DataType type,
                          int width, int height, double* geoTransform,
@@ -419,6 +420,16 @@ class CORE_EXPORT QgsRasterDataProvider : public QgsDataProvider, public QgsRast
       Q_UNUSED( createOptions );
       return false;
     }
+#endif
+
+    static QgsRasterDataProvider* create( const QString &providerKey,
+                                          const QString &uri,
+                                          const QString& format, int nBands,
+                                          QGis::DataType type,
+                                          int width, int height, double* geoTransform,
+                                          const QgsCoordinateReferenceSystem& crs,
+                                          QStringList createOptions = QStringList() );
+
 
     /** Set no data value on created dataset
      *  @param bandNo band number

src/core/raster/qgsrasterfilewriter.cpp

@@ -873,11 +873,11 @@ QgsRasterDataProvider* QgsRasterFileWriter::createPartProvider( const QgsRectang
 
   QString outputFile = outputUrl + "/" + partFileName( fileIndex );
   //QgsRasterDataProvider* destProvider = QgsRasterLayer::loadProvider( mOutputProviderKey, outputFile );
-  QgsRasterDataProvider* destProvider = ( QgsRasterDataProvider* ) QgsProviderRegistry::instance()->provider( mOutputProviderKey, outputFile );
+  //QgsRasterDataProvider* destProvider = ( QgsRasterDataProvider* ) QgsProviderRegistry::instance()->provider( mOutputProviderKey, outputFile );
-  if ( !destProvider )
+  //if ( !destProvider )
-  {
+  //{
-    return 0;
+  //  return 0;
-  }
+  //}
 
   //geotransform
   double geoTransform[6];
@@ -889,12 +889,29 @@ QgsRasterDataProvider* QgsRasterFileWriter::createPartProvider( const QgsRectang
   geoTransform[5] = -mup;
 
   // perhaps we need a separate createOptions for tiles ?
-  if ( !destProvider->create( mOutputFormat, nBands, type, iterCols, iterRows, geoTransform,
+  /*
-                              crs ) )
+    if ( !destProvider->create( mOutputFormat, nBands, type, iterCols, iterRows, geoTransform,
+                                crs ) )
+    {
+      delete destProvider;
+      return 0;
+    }
+  */
+
+  QgsRasterDataProvider* destProvider = QgsRasterDataProvider::create( mOutputProviderKey, mOutputUrl, mOutputFormat, nBands, type, iterCols, iterRows, geoTransform, crs, mCreateOptions ) ;
+
+  if ( !destProvider )
+  {
+    return 0;
+  }
+
+  // TODO: return provider and report error
+  if ( !destProvider->isValid() )
   {
     delete destProvider;
     return 0;
   }
+
   return destProvider;
 }
 
@@ -909,24 +926,35 @@ QgsRasterDataProvider* QgsRasterFileWriter::initOutput( int nCols, int nRows, co
   }
   else
   {
-    //QgsRasterDataProvider* destProvider = QgsRasterLayer::loadProvider( mOutputProviderKey, mOutputUrl );
-    QgsRasterDataProvider* destProvider = ( QgsRasterDataProvider* ) QgsProviderRegistry::instance()->provider( mOutputProviderKey, mOutputUrl );
-    if ( !destProvider )
-    {
-      return 0;
-    }
-
     // TODO enable "use existing", has no effect for now, because using Create() in gdal provider
     // should this belong in provider? should also test that source provider is gdal
     // if ( mBuildPyramidsFlag == -4 && mOutputProviderKey == "gdal" && mOutputFormat.toLower() == "gtiff" )
     //   mCreateOptions << "COPY_SRC_OVERVIEWS=YES";
 
-    if ( !destProvider->create( mOutputFormat, nBands, type, nCols, nRows, geoTransform,
+    //QgsRasterDataProvider* destProvider = QgsRasterLayer::loadProvider( mOutputProviderKey, mOutputUrl );
-                                crs, mCreateOptions ) )
+    //QgsRasterDataProvider* destProvider = ( QgsRasterDataProvider* ) QgsProviderRegistry::instance()->provider( mOutputProviderKey, mOutputUrl );
+    QgsRasterDataProvider* destProvider = QgsRasterDataProvider::create( mOutputProviderKey, mOutputUrl, mOutputFormat, nBands, type, nCols, nRows, geoTransform, crs, mCreateOptions ) ;
+
+    if ( !destProvider )
+    {
+      return 0;
+    }
+
+    // TODO: return provider and report error
+    if ( !destProvider->isValid() )
     {
       delete destProvider;
       return 0;
     }
+
+    /*
+        if ( !destProvider->create( mOutputFormat, nBands, type, nCols, nRows, geoTransform,
+                                    crs, mCreateOptions ) )
+        {
+          delete destProvider;
+          return 0;
+        }
+    */
     return destProvider;
   }
 }

src/providers/gdal/qgsgdalprovider.cpp

@@ -92,10 +92,17 @@ int CPL_STDCALL progressCallback( double dfComplete,
   return true;
 }
 
+QgsGdalProvider::QgsGdalProvider( QString const & uri, QgsError error )
+    : QgsRasterDataProvider( uri )
+    , mValid( false )
+{
+  setError( error );
+}
 
-QgsGdalProvider::QgsGdalProvider( QString const & uri )
+QgsGdalProvider::QgsGdalProvider( QString const & uri, bool update )
     : QgsRasterDataProvider( uri )
     , QgsGdalProviderBase()
+    , mUpdate( update )
     , mValid( true )
 {
   QgsDebugMsg( "QgsGdalProvider: constructing with uri '" + uri + "'." );
@@ -126,28 +133,11 @@ QgsGdalProvider::QgsGdalProvider( QString const & uri )
       setDataSourceUri( vsiPrefix + uri );
     QgsDebugMsg( QString( "Trying %1 syntax, uri= %2" ).arg( vsiPrefix ).arg( dataSourceUri() ) );
   }
-  else
-  {
-    // TODO: this constructor is also called for new rasters, in that case GDAL prints error:
-    // "ERROR 4: `pok.tif' does not exist in the file system, and is not recognised as a supported dataset name."
-    // To avoid this message, we test first if the file exists at all.
-    // This should be done better adding static create() method or something like that
-    // TODO: Cannot test for file existence, for example NetCDF with sublayers
-    // is using URI: NETCDF:"/path/to/file.cdf":layer1
-    /*
-    if ( !QFile::exists( uri ) )
-    {
-      QString msg = QString( "File does not exist: %1" ).arg( dataSourceUri() );
-      appendError( ERR( msg ) );
-      return;
-    }
-    */
-  }
 
   QString gdalUri = dataSourceUri();
 
   CPLErrorReset();
-  mGdalBaseDataset = GDALOpen( TO8F( gdalUri ), GA_ReadOnly );
+  mGdalBaseDataset = GDALOpen( TO8F( gdalUri ), mUpdate ? GA_Update : GA_ReadOnly );
 
   if ( !mGdalBaseDataset )
   {
@@ -1481,7 +1471,7 @@ QString QgsGdalProvider::buildPyramids( QList<QgsRasterPyramid> const & theRaste
       //something bad happenend
       //QString myString = QString (CPLGetLastError());
       GDALClose( mGdalBaseDataset );
-      mGdalBaseDataset = GDALOpen( TO8F( dataSourceUri() ), GA_ReadOnly );
+      mGdalBaseDataset = GDALOpen( TO8F( dataSourceUri() ), mUpdate ? GA_Update : GA_ReadOnly );
       //Since we are not a virtual warped dataset, mGdalDataSet and mGdalBaseDataset are supposed to be the same
       mGdalDataset = mGdalBaseDataset;
 
@@ -1523,7 +1513,7 @@ QString QgsGdalProvider::buildPyramids( QList<QgsRasterPyramid> const & theRaste
     QgsDebugMsg( "Reopening dataset ..." );
     //close the gdal dataset and reopen it in read only mode
     GDALClose( mGdalBaseDataset );
-    mGdalBaseDataset = GDALOpen( TO8F( dataSourceUri() ), GA_ReadOnly );
+    mGdalBaseDataset = GDALOpen( TO8F( dataSourceUri() ), mUpdate ? GA_Update : GA_ReadOnly );
     //Since we are not a virtual warped dataset, mGdalDataSet and mGdalBaseDataset are supposed to be the same
     mGdalDataset = mGdalBaseDataset;
   }
@@ -2401,17 +2391,27 @@ char** papszFromStringList( const QStringList& list )
   return papszRetList;
 }
 
+#if 0
 bool QgsGdalProvider::create( const QString& format, int nBands,
                               QGis::DataType type,
                               int width, int height, double* geoTransform,
                               const QgsCoordinateReferenceSystem& crs,
                               QStringList createOptions )
+#endif
+QGISEXTERN QgsGdalProvider * create(
+  const QString &uri,
+  const QString& format, int nBands,
+  QGis::DataType type,
+  int width, int height, double* geoTransform,
+  const QgsCoordinateReferenceSystem& crs,
+  QStringList createOptions )
 {
   //get driver
   GDALDriverH driver = GDALGetDriverByName( format.toLocal8Bit().data() );
   if ( !driver )
   {
-    return false;
+    QgsError error( "Cannot load GDAL driver " + format, "GDAL provider" );
+    return new QgsGdalProvider( uri, error );
   }
 
   QString tmpStr = "create options:";
@@ -2420,27 +2420,21 @@ bool QgsGdalProvider::create( const QString& format, int nBands,
   QgsDebugMsg( tmpStr );
 
   //create dataset
+  CPLErrorReset();
   char **papszOptions = papszFromStringList( createOptions );
-  GDALDatasetH dataset = GDALCreate( driver, dataSourceUri().toLocal8Bit().data(), width, height, nBands, ( GDALDataType )type, papszOptions );
+  GDALDatasetH dataset = GDALCreate( driver, uri.toLocal8Bit().data(), width, height, nBands, ( GDALDataType )type, papszOptions );
   CSLDestroy( papszOptions );
   if ( dataset == NULL )
   {
-    return false;
+    QgsError error( QString( "Cannot create new dataset  %1:\n%2" ).arg( uri ).arg( QString::fromUtf8( CPLGetLastErrorMsg() ) ), "GDAL provider" );
+    return new QgsGdalProvider( uri, error );
   }
 
-  mGeoTransform[0] = geoTransform[0];
+  GDALSetGeoTransform( dataset, geoTransform );
-  mGeoTransform[1] = geoTransform[1];
-  mGeoTransform[2] = geoTransform[2];
-  mGeoTransform[3] = geoTransform[3];
-  mGeoTransform[4] = geoTransform[4];
-  mGeoTransform[5] = geoTransform[5];
-
-  GDALSetGeoTransform( dataset, mGeoTransform );
   GDALSetProjection( dataset, crs.toWkt().toLocal8Bit().data() );
+  GDALClose( dataset );
 
-  mGdalBaseDataset = dataset;
+  return new QgsGdalProvider( uri, true );
-  initBaseDataset();
-  return mValid;
 }
 
 bool QgsGdalProvider::write( void* data, int band, int width, int height, int xOffset, int yOffset )

src/providers/gdal/qgsgdalprovider.h

@@ -65,7 +65,10 @@ class QgsGdalProvider : public QgsRasterDataProvider, QgsGdalProviderBase
     *                otherwise we contact the host directly.
     *
     */
-    QgsGdalProvider( QString const & uri = 0 );
+    QgsGdalProvider( QString const & uri = 0, bool update = false );
+
+    /** Create invalid provider with error */
+    QgsGdalProvider( QString const & uri, QgsError error );
 
     //! Destructor
     ~QgsGdalProvider();
@@ -234,11 +237,13 @@ class QgsGdalProvider : public QgsRasterDataProvider, QgsGdalProviderBase
 
     /** Creates a new dataset with mDataSourceURI
         @return true in case of success*/
+    /*
     bool create( const QString& format, int nBands,
                  QGis::DataType type,
                  int width, int height, double* geoTransform,
                  const QgsCoordinateReferenceSystem& crs,
                  QStringList createOptions = QStringList() );
+    */
 
     /**Writes into the provider datasource*/
     bool write( void* data, int band, int width, int height, int xOffset, int yOffset );
@@ -257,6 +262,9 @@ class QgsGdalProvider : public QgsRasterDataProvider, QgsGdalProviderBase
     void statusChanged( QString );
 
   private:
+    // update mode
+    bool mUpdate;
+
     // initialize CRS from wkt
     bool crsFromWkt( const char *wkt );
 

src/providers/grass/qgsgrassgislib.cpp

@@ -573,12 +573,6 @@ int QgsGrassGisLib::G_open_raster_new( const char *name, RASTER_MAP_TYPE wr_type
   raster.name = name;
   //raster.writer = new QgsRasterFileWriter( dataSource );
 
-  raster.provider = ( QgsRasterDataProvider* )QgsProviderRegistry::instance()->provider( providerKey, dataSource );
-  if ( !raster.provider )
-  {
-    fatal( "Cannot load raster provider with data source: " + dataSource );
-  }
-
   QString outputFormat = "GTiff";
   int nBands = 1;
   QGis::DataType type = qgisRasterType( wr_type );
@@ -591,11 +585,13 @@ int QgsGrassGisLib::G_open_raster_new( const char *name, RASTER_MAP_TYPE wr_type
   geoTransform[4] = 0.0;
   geoTransform[5] = -1. * mExtent.height() / mRows;
 
-  if ( !raster.provider->create( outputFormat, nBands, type, mColumns, mRows, geoTransform, mCrs ) )
+  raster.provider = QgsRasterDataProvider::create( providerKey, dataSource, outputFormat, nBands, type, mColumns, mRows, geoTransform, mCrs );
+  if ( !raster.provider || !raster.provider->isValid() )
   {
-    delete raster.provider;
+    if ( raster.provider ) delete raster.provider;
     fatal( "Cannot create output data source: " + dataSource );
   }
+
   raster.band = 1;
   double noDataValue = std::numeric_limits<double>::quiet_NaN();
   switch ( wr_type )