[FEATURE] Allow copying features from QGIS in GeoJSON format

The previous setting for include WKT when copying features has been
replaced with a choice of copying features as "Plain text, attributes
only", "Plain text, WKT geometry" and a new "GeoJSON" option.

When set to "GeoJSON", copying features in QGIS will place a GeoJSON
text representation of the features on the clipboard for easy
pasting into other applications/javascript code.

Sponsored by North Road

src/app/qgsclipboard.cpp

@@ -34,6 +34,7 @@
 #include "qgslogger.h"
 #include "qgsvectorlayer.h"
 #include "qgsogrutils.h"
+#include "qgsjsonutils.h"
 
 QgsClipboard::QgsClipboard()
     : QObject()
@@ -76,56 +77,81 @@ void QgsClipboard::replaceWithCopyOf( QgsFeatureStore & featureStore )
   emit changed();
 }
 
-void QgsClipboard::setSystemClipboard()
+QString QgsClipboard::generateClipboardText() const
 {
-  // Replace the system clipboard.
   QSettings settings;
-  bool copyWKT = settings.value( "qgis/copyGeometryAsWKT", true ).toBool();
-
-  QStringList textLines;
-  QStringList textFields;
-
-  // first do the field names
-  if ( copyWKT )
+  CopyFormat format = AttributesWithWKT;
+  if ( settings.contains( "/qgis/copyFeatureFormat" ) )
+    format = static_cast< CopyFormat >( settings.value( "/qgis/copyFeatureFormat", true ).toInt() );
+  else
   {
-    textFields += "wkt_geom";
+    //old format setting
+    format = settings.value( "/qgis/copyGeometryAsWKT", true ).toBool() ? AttributesWithWKT : AttributesOnly;
   }
 
-  Q_FOREACH ( const QgsField& field, mFeatureFields )
+  switch ( format )
   {
-    textFields += field.name();
-  }
-  textLines += textFields.join( "\t" );
-  textFields.clear();
+    case AttributesOnly:
+    case AttributesWithWKT:
+    {
+      QStringList textLines;
+      QStringList textFields;
 
-  // then the field contents
-  for ( QgsFeatureList::const_iterator it = mFeatureClipboard.constBegin(); it != mFeatureClipboard.constEnd(); ++it )
-  {
-    QgsAttributes attributes = it->attributes();
+      // first do the field names
+      if ( format == AttributesWithWKT )
+      {
+        textFields += "wkt_geom";
+      }
 
-    // TODO: Set up Paste Transformations to specify the order in which fields are added.
-    if ( copyWKT )
-    {
-      if ( it->constGeometry() )
-        textFields += it->constGeometry()->exportToWkt();
-      else
+      Q_FOREACH ( const QgsField& field, mFeatureFields )
       {
-        textFields += settings.value( "qgis/nullValue", "NULL" ).toString();
+        textFields += field.name();
       }
-    }
+      textLines += textFields.join( "\t" );
+      textFields.clear();
 
-    // QgsDebugMsg("about to traverse fields.");
-    for ( int idx = 0; idx < attributes.count(); ++idx )
+      // then the field contents
+      for ( QgsFeatureList::const_iterator it = mFeatureClipboard.constBegin(); it != mFeatureClipboard.constEnd(); ++it )
+      {
+        QgsAttributes attributes = it->attributes();
+
+        // TODO: Set up Paste Transformations to specify the order in which fields are added.
+        if ( format == AttributesWithWKT )
+        {
+          if ( it->constGeometry() )
+            textFields += it->constGeometry()->exportToWkt();
+          else
+          {
+            textFields += settings.value( "qgis/nullValue", "NULL" ).toString();
+          }
+        }
+
+        // QgsDebugMsg("about to traverse fields.");
+        for ( int idx = 0; idx < attributes.count(); ++idx )
+        {
+          // QgsDebugMsg(QString("inspecting field '%1'.").arg(it2->toString()));
+          textFields += attributes.at( idx ).toString();
+        }
+
+        textLines += textFields.join( "\t" );
+        textFields.clear();
+      }
+
+      return textLines.join( "\n" );
+    }
+    case GeoJSON:
     {
-      // QgsDebugMsg(QString("inspecting field '%1'.").arg(it2->toString()));
-      textFields += attributes.at( idx ).toString();
+      QgsJSONExporter exporter;
+      exporter.setSourceCrs( mCRS );
+      return exporter.exportFeatures( mFeatureClipboard );
     }
-
-    textLines += textFields.join( "\t" );
-    textFields.clear();
   }
+  return QString();
+}
 
-  QString textCopy = textLines.join( "\n" );
+void QgsClipboard::setSystemClipboard()
+{
+  QString textCopy = generateClipboardText();
 
   QClipboard *cb = QApplication::clipboard();
 

src/app/qgsclipboard.h

@@ -53,6 +53,15 @@ class APP_EXPORT QgsClipboard : public QObject
 {
     Q_OBJECT
   public:
+
+    //! Available formats for copying features as text
+    enum CopyFormat
+    {
+      AttributesOnly, /*!< Tab delimited text, attributes only */
+      AttributesWithWKT, /*!< Tab delimited text, with geometry in WKT format */
+      GeoJSON, /*!< GeoJSON FeatureCollection format */
+    };
+
     /**
      * Constructor for the clipboard.
      */
@@ -146,6 +155,11 @@ class APP_EXPORT QgsClipboard : public QObject
      */
     void setSystemClipboard();
 
+    /** Creates a text representation of the clipboard features.
+     * @returns clipboard text, respecting user export format
+     */
+    QString generateClipboardText() const;
+
     /** Attempts to convert a string to a list of features, by parsing the string as WKT and GeoJSON
      * @param string string to convert
      * @param fields fields for resultant features
@@ -169,6 +183,9 @@ class APP_EXPORT QgsClipboard : public QObject
 
     /** True when the data from the system clipboard should be read */
     bool mUseSystemClipboard;
+
+    friend class TestQgisAppClipboard;
+
 };
 
 #endif

src/app/qgsoptions.cpp

@@ -42,6 +42,7 @@
 #include "qgscolordialog.h"
 #include "qgsexpressioncontext.h"
 #include "qgsunittypes.h"
+#include "qgsclipboard.h"
 
 #include <QInputDialog>
 #include <QFileDialog>
@@ -604,7 +605,15 @@ QgsOptions::QgsOptions( QWidget *parent, Qt::WindowFlags fl )
   cbxEvaluateDefaultValues->setChecked( mSettings->value( "/qgis/evaluateDefaultValues", false ).toBool() );
   cbxCompileExpressions->setChecked( mSettings->value( "/qgis/compileExpressions", true ).toBool() );
   cbxCreateRasterLegendIcons->setChecked( mSettings->value( "/qgis/createRasterLegendIcons", false ).toBool() );
-  cbxCopyWKTGeomFromTable->setChecked( mSettings->value( "/qgis/copyGeometryAsWKT", true ).toBool() );
+
+  mComboCopyFeatureFormat->addItem( tr( "Plain text, no geometry" ), QgsClipboard::AttributesOnly );
+  mComboCopyFeatureFormat->addItem( tr( "Plain text, WKT geometry" ), QgsClipboard::AttributesWithWKT );
+  mComboCopyFeatureFormat->addItem( tr( "GeoJSON" ), QgsClipboard::GeoJSON );
+  if ( mSettings->contains( "/qgis/copyFeatureFormat" ) )
+    mComboCopyFeatureFormat->setCurrentIndex( mComboCopyFeatureFormat->findData( mSettings->value( "/qgis/copyFeatureFormat", true ).toInt() ) );
+  else
+    mComboCopyFeatureFormat->setCurrentIndex( mComboCopyFeatureFormat->findData( mSettings->value( "/qgis/copyGeometryAsWKT", true ).toBool() ?
+        QgsClipboard::AttributesWithWKT : QgsClipboard::AttributesOnly ) );
   leNullValue->setText( mSettings->value( "qgis/nullValue", "NULL" ).toString() );
   cbxIgnoreShapeEncoding->setChecked( mSettings->value( "/qgis/ignoreShapeEncoding", true ).toBool() );
   cbxCanvasRotation->setChecked( QgsMapCanvas::rotationEnabled() );
@@ -1157,7 +1166,8 @@ void QgsOptions::saveOptions()
   mSettings->setValue( "/qgis/defaultLegendGraphicResolution", mLegendGraphicResolutionSpinBox->value() );
   bool createRasterLegendIcons = mSettings->value( "/qgis/createRasterLegendIcons", false ).toBool();
   mSettings->setValue( "/qgis/createRasterLegendIcons", cbxCreateRasterLegendIcons->isChecked() );
-  mSettings->setValue( "/qgis/copyGeometryAsWKT", cbxCopyWKTGeomFromTable->isChecked() );
+  mSettings->setValue( "/qgis/copyFeatureFormat", mComboCopyFeatureFormat->itemData( mComboCopyFeatureFormat->currentIndex() ).toInt() );
+
   mSettings->setValue( "/qgis/new_layers_visible", chkAddedVisibility->isChecked() );
   mSettings->setValue( "/qgis/enable_anti_aliasing", chkAntiAliasing->isChecked() );
   mSettings->setValue( "/qgis/enable_render_caching", chkUseRenderCaching->isChecked() );