Return an invalid iterator if a transform exception occurs

when projecting filter rects from destination crs

Author: nyalldawson

python/core/qgsfeatureiterator.sip

@@ -120,6 +120,7 @@ end of iterating: free the resources / lock
  the requested filterRect() transformed to the source's coordinate reference system.
  Iterators should call this method and use the returned rectangle for filtering
  features to ensure that any QgsFeatureRequest.destinationCrs() set on the request is respected.
+ Will throw a QgsCsException if the rect cannot be transformed from the destination CRS.
 .. versionadded:: 3.0
  :rtype: QgsRectangle
 %End

src/core/providers/memory/qgsmemoryfeatureiterator.cpp

@@ -21,6 +21,7 @@
 #include "qgsspatialindex.h"
 #include "qgsmessagelog.h"
 #include "qgsproject.h"
+#include "qgscsexception.h"
 
 ///@cond PRIVATE
 
@@ -31,7 +32,16 @@ QgsMemoryFeatureIterator::QgsMemoryFeatureIterator( QgsMemoryFeatureSource *sour
   {
     mTransform = QgsCoordinateTransform( mSource->mCrs, mRequest.destinationCrs() );
   }
-  mFilterRect = filterRectToSourceCrs( mTransform );
+  try
+  {
+    mFilterRect = filterRectToSourceCrs( mTransform );
+  }
+  catch ( QgsCsException & )
+  {
+    // can't reproject mFilterRect
+    mClosed = true;
+    return;
+  }
 
   if ( !mSource->mSubsetString.isEmpty() )
   {

src/core/qgscachedfeatureiterator.cpp

@@ -15,6 +15,7 @@
 
 #include "qgscachedfeatureiterator.h"
 #include "qgsvectorlayercache.h"
+#include "qgscsexception.h"
 
 QgsCachedFeatureIterator::QgsCachedFeatureIterator( QgsVectorLayerCache *vlCache, const QgsFeatureRequest &featureRequest )
   : QgsAbstractFeatureIterator( featureRequest )
@@ -24,7 +25,16 @@ QgsCachedFeatureIterator::QgsCachedFeatureIterator( QgsVectorLayerCache *vlCache
   {
     mTransform = QgsCoordinateTransform( mVectorLayerCache->sourceCrs(), mRequest.destinationCrs() );
   }
-  mFilterRect = filterRectToSourceCrs( mTransform );
+  try
+  {
+    mFilterRect = filterRectToSourceCrs( mTransform );
+  }
+  catch ( QgsCsException & )
+  {
+    // can't reproject mFilterRect
+    mClosed = true;
+    return;
+  }
   if ( !mFilterRect.isNull() )
   {
     // update request to be the unprojected filter rect
@@ -101,7 +111,16 @@ QgsCachedFeatureWriterIterator::QgsCachedFeatureWriterIterator( QgsVectorLayerCa
   {
     mTransform = QgsCoordinateTransform( mVectorLayerCache->sourceCrs(), mRequest.destinationCrs() );
   }
-  mFilterRect = filterRectToSourceCrs( mTransform );
+  try
+  {
+    mFilterRect = filterRectToSourceCrs( mTransform );
+  }
+  catch ( QgsCsException & )
+  {
+    // can't reproject mFilterRect
+    mClosed = true;
+    return;
+  }
   if ( !mFilterRect.isNull() )
   {
     // update request to be the unprojected filter rect

src/core/qgsfeatureiterator.cpp

@@ -124,15 +124,7 @@ QgsRectangle QgsAbstractFeatureIterator::filterRectToSourceCrs( const QgsCoordin
   if ( mRequest.filterRect().isNull() )
     return QgsRectangle();
 
-  try
-  {
-    return transform.transformBoundingBox( mRequest.filterRect(), QgsCoordinateTransform::ReverseTransform );
-  }
-  catch ( QgsCsException & )
-  {
-    // can't reproject mFilterRect
-    return mRequest.filterRect();
-  }
+  return transform.transformBoundingBox( mRequest.filterRect(), QgsCoordinateTransform::ReverseTransform );
 }
 
 void QgsAbstractFeatureIterator::ref()

src/core/qgsfeatureiterator.h

@@ -131,6 +131,7 @@ class CORE_EXPORT QgsAbstractFeatureIterator
      * the requested filterRect() transformed to the source's coordinate reference system.
      * Iterators should call this method and use the returned rectangle for filtering
      * features to ensure that any QgsFeatureRequest::destinationCrs() set on the request is respected.
+     * Will throw a QgsCsException if the rect cannot be transformed from the destination CRS.
      * \since QGIS 3.0
      */
     QgsRectangle filterRectToSourceCrs( const QgsCoordinateTransform &transform ) const;

src/core/qgsvectorlayerfeatureiterator.cpp

@@ -25,6 +25,7 @@
 #include "qgsdistancearea.h"
 #include "qgsproject.h"
 #include "qgsmessagelog.h"
+#include "qgscsexception.h"
 
 QgsVectorLayerFeatureSource::QgsVectorLayerFeatureSource( const QgsVectorLayer *layer )
 {
@@ -113,7 +114,16 @@ QgsVectorLayerFeatureIterator::QgsVectorLayerFeatureIterator( QgsVectorLayerFeat
   {
     mTransform = QgsCoordinateTransform( mSource->mCrs, mRequest.destinationCrs() );
   }
-  mFilterRect = filterRectToSourceCrs( mTransform );
+  try
+  {
+    mFilterRect = filterRectToSourceCrs( mTransform );
+  }
+  catch ( QgsCsException & )
+  {
+    // can't reproject mFilterRect
+    mClosed = true;
+    return;
+  }
   if ( !mFilterRect.isNull() )
   {
     // update request to be the unprojected filter rect

src/providers/arcgisrest/qgsafsfeatureiterator.cpp

@@ -17,7 +17,7 @@
 #include "qgsafsprovider.h"
 #include "qgsmessagelog.h"
 #include "geometry/qgsgeometry.h"
-
+#include "qgscsexception.h"
 
 QgsAfsFeatureSource::QgsAfsFeatureSource( const QgsAfsProvider *provider )
 // FIXME: ugly const_cast...
@@ -45,7 +45,16 @@ QgsAfsFeatureIterator::QgsAfsFeatureIterator( QgsAfsFeatureSource *source, bool
   {
     mTransform = QgsCoordinateTransform( mSource->mCrs, mRequest.destinationCrs() );
   }
-  mFilterRect = filterRectToSourceCrs( mTransform );
+  try
+  {
+    mFilterRect = filterRectToSourceCrs( mTransform );
+  }
+  catch ( QgsCsException & )
+  {
+    // can't reproject mFilterRect
+    mClosed = true;
+    return;
+  }
 }
 
 QgsAfsFeatureIterator::~QgsAfsFeatureIterator()

src/providers/db2/qgsdb2featureiterator.cpp

@@ -22,6 +22,7 @@
 #include "qgssettings.h"
 #include "qgslogger.h"
 #include "qgsgeometry.h"
+#include "qgscsexception.h"
 
 #include <QObject>
 #include <QTextStream>
@@ -37,7 +38,16 @@ QgsDb2FeatureIterator::QgsDb2FeatureIterator( QgsDb2FeatureSource *source, bool
   {
     mTransform = QgsCoordinateTransform( mSource->mCrs, mRequest.destinationCrs() );
   }
-  mFilterRect = filterRectToSourceCrs( mTransform );
+  try
+  {
+    mFilterRect = filterRectToSourceCrs( mTransform );
+  }
+  catch ( QgsCsException & )
+  {
+    // can't reproject mFilterRect
+    mClosed = true;
+    return;
+  }
 
   BuildStatement( request );
 

src/providers/delimitedtext/qgsdelimitedtextfeatureiterator.cpp

@@ -43,7 +43,16 @@ QgsDelimitedTextFeatureIterator::QgsDelimitedTextFeatureIterator( QgsDelimitedTe
   {
     mTransform = QgsCoordinateTransform( mSource->mCrs, mRequest.destinationCrs() );
   }
-  mFilterRect = filterRectToSourceCrs( mTransform );
+  try
+  {
+    mFilterRect = filterRectToSourceCrs( mTransform );
+  }
+  catch ( QgsCsException & )
+  {
+    // can't reproject mFilterRect
+    mClosed = true;
+    return;
+  }
 
   if ( !mFilterRect.isNull() && hasGeometry )
   {

src/providers/gpx/qgsgpxfeatureiterator.cpp

@@ -20,6 +20,7 @@
 #include "qgsgeometry.h"
 #include "qgslogger.h"
 #include "qgsmessagelog.h"
+#include "qgscsexception.h"
 
 #include <limits>
 #include <cstring>
@@ -32,7 +33,16 @@ QgsGPXFeatureIterator::QgsGPXFeatureIterator( QgsGPXFeatureSource *source, bool
   {
     mTransform = QgsCoordinateTransform( mSource->mCrs, mRequest.destinationCrs() );
   }
-  mFilterRect = filterRectToSourceCrs( mTransform );
+  try
+  {
+    mFilterRect = filterRectToSourceCrs( mTransform );
+  }
+  catch ( QgsCsException & )
+  {
+    // can't reproject mFilterRect
+    mClosed = true;
+    return;
+  }
 
   rewind();
 }