Add Drag & Drop support for CSV files in PDI

onStart.groovy

import org.w3c.dom.*

import org.pentaho.di.core.*
import org.pentaho.di.core.exception.*
import org.pentaho.di.core.gui.*
import org.pentaho.di.core.plugins.*
import org.pentaho.di.trans.step.*
import org.pentaho.di.ui.spoon.*

class CsvListener implements FileListener {


  public boolean open( Node transNode, String fname, boolean importfile ) throws KettleMissingPluginsException {
    def csvInputPlugin = PluginRegistry.instance.findPluginWithName(StepPluginType, 'CSV file input')
    def csvInputMetaClass = PluginRegistry.instance.loadClass(csvInputPlugin)
    csvInputMetaClass.setDefault()
    def pid = PluginRegistry.instance.getPluginId(csvInputPlugin.pluginType, csvInputMetaClass)
	def csv = new StepMeta(pid, csvInputPlugin.name, csvInputMetaClass)
    csv.stepMetaInterface.setFilename(fname)
    csv.setName(fname?.substring(fname?.lastIndexOf(File.separator)+1,fname?.indexOf('.')) ?: 'CSV file input')
    csv?.location= new Point(20,20)
    csv?.draw = true
    Spoon.instance.activeTransformation?.addStep(csv)
    Spoon.instance.activeTransGraph?.redraw()
    true
  }

  public boolean save( EngineMetaInterface meta, String fname, boolean isExport ){
    false
  }
  
  public void syncMetaName( EngineMetaInterface meta, String name ){
    
  }
  
  public boolean accepts( String fileName ){
    def x = Arrays.asList(getSupportedExtensions()).contains(fileName?.substring(fileName?.indexOf('.')+1))
  }

  public boolean acceptsXml( String nodeName ){
    false
  }

  public String[] getSupportedExtensions(){
    ['csv'] as String[]
  }

  public String[] getFileTypeDisplayNames( Locale locale ){
    ['CSV'] as String[]
  }

  public String getRootNodeName(){
    null
  }
}

Spoon.instance.addFileListener(new CsvListener())