QGIS/python/plugins/db_manager/dlg_export_vector.py

# -*- coding: utf-8 -*-

"""
/***************************************************************************
Name                 : DB Manager
Description          : Database manager plugin for QGIS
Date                 : Oct 13, 2011
copyright            : (C) 2011 by Giuseppe Sucameli
email                : brush.tyler@gmail.com

The content of this file is based on
- PG_Manager by Martin Dobias (GPLv2 license)
 ***************************************************************************/

/***************************************************************************
 *                                                                         *
 *   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.                                   *
 *                                                                         *
 ***************************************************************************/
"""

from PyQt4.QtCore import *
from PyQt4.QtGui import *

import qgis.core
from qgis.utils import iface

from .ui.ui_DlgExportVector import Ui_DbManagerDlgExportVector as Ui_Dialog

class DlgExportVector(QDialog, Ui_Dialog):

	def __init__(self, inLayer, inDb, parent=None):
		QDialog.__init__(self, parent)
		self.inLayer = inLayer
		self.db = inDb
		self.setupUi(self)

		# update UI
		self.setupWorkingMode()
		self.populateEncodings()

	def setupWorkingMode(self):
		# set default values
		inCrs = self.inLayer.crs()
		srid = inCrs.postgisSrid() if inCrs.isValid() else 4236
		self.editSourceSrid.setText( "%s" % srid )
		self.editTargetSrid.setText( "%s" % srid )

		QObject.connect( self.btnChooseOutputFile, SIGNAL("clicked()"), self.chooseOutputFile )
		self.checkSupports()

	def checkSupports(self):
		""" update options available for the current input layer """
		allowSpatial = self.db.connector.hasSpatialSupport()
		hasGeomType = self.inLayer and self.inLayer.hasGeometryType()
		self.chkSourceSrid.setEnabled(allowSpatial and hasGeomType)
		self.chkTargetSrid.setEnabled(allowSpatial and hasGeomType)
		#self.chkSpatialIndex.setEnabled(allowSpatial and hasGeomType)


	def chooseOutputFile(self):
		# get last used dir and format
		settings = QSettings()
		lastDir = settings.value("/db_manager/lastUsedDir", "")
		# ask for a filename
		filename = QFileDialog.getSaveFileName(self, self.tr("Choose where to save the file"), lastDir, self.tr("Shapefiles") + " (*.shp)")
		if filename == "":
			return
		if filename[-4:] != ".shp":
			filename += ".shp"
		# store the last used dir and format
		settings.setValue("/db_manager/lastUsedDir", QFileInfo(filename).filePath())

		self.editOutputFile.setText( filename )

	def populateEncodings(self):
		# populate the combo with supported encodings
		self.cboEncoding.addItems(qgis.core.QgsVectorDataProvider.availableEncodings())

		# set the last used encoding
		settings = QSettings()
		enc = self.inLayer.dataProvider().encoding()
		idx = self.cboEncoding.findText( enc )
		if idx < 0:
			self.cboEncoding.insertItem( 0, enc )
			idx = 0
		self.cboEncoding.setCurrentIndex( idx )

	def accept(self):
		# sanity checks
		if self.editOutputFile.text() == "":
			QMessageBox.information(self, self.tr("Export to file"), self.tr("Output table name is required"))
			return

		if self.chkSourceSrid.isEnabled() and self.chkSourceSrid.isChecked():
			try:
				sourceSrid = int(self.editSourceSrid.text())
			except ValueError:
				QMessageBox.information(self, self.tr("Export to file"), self.tr("Invalid source srid: must be an integer"))
				return

		if self.chkTargetSrid.isEnabled() and self.chkTargetSrid.isChecked():
			try:
				targetSrid = int(self.editTargetSrid.text())
			except ValueError:
				QMessageBox.information(self, self.tr("Export to file"), self.tr("Invalid target srid: must be an integer"))
				return

		# override cursor
		QApplication.setOverrideCursor(QCursor(Qt.WaitCursor))
		# store current input layer crs, so I can restore it later
		prevInCrs = self.inLayer.crs()
		try:
			uri = self.editOutputFile.text()
			providerName = "ogr"
			driverName = "ESRI Shapefile"

			options = {}

			# set the OGR driver will be used
                        options['driverName'] = driverName
			# set the output file encoding
			if self.chkEncoding.isEnabled() and self.chkEncoding.isChecked():
				enc = self.cboEncoding.currentText()
				options['fileEncoding'] = enc

			if self.radCreate.isChecked() and self.chkDropTable.isChecked():
				options['overwrite'] = True
			elif self.radAppend.isChecked():
				options['append'] = True

			outCrs = None
			if self.chkTargetSrid.isEnabled() and self.chkTargetSrid.isChecked():
				targetSrid = int(self.editTargetSrid.text())
				outCrs = qgis.core.QgsCoordinateReferenceSystem(targetSrid)

			# update input layer crs
			if self.chkSourceSrid.isEnabled() and self.chkSourceSrid.isChecked():
				sourceSrid = int(self.editSourceSrid.text())
				inCrs = qgis.core.QgsCoordinateReferenceSystem(sourceSrid)
				self.inLayer.setCrs( inCrs )

			# do the export!
			ret, errMsg = qgis.core.QgsVectorLayerImport.importLayer( self.inLayer, uri, providerName, outCrs, False, False, options )
		except Exception as e:
			ret = -1
			errMsg = unicode( e )

		finally:
			# restore input layer crs and encoding
			self.inLayer.setCrs( prevInCrs )
			# restore cursor
			QApplication.restoreOverrideCursor()

		if ret != 0:
			QMessageBox.warning(self, self.tr("Export to file"), self.tr("Error %d\n%s") % (ret, errMsg) )
			return

		# create spatial index
		#if self.chkSpatialIndex.isEnabled() and self.chkSpatialIndex.isChecked():
		#	self.db.connector.createSpatialIndex( (schema, table), geom )

		QMessageBox.information(self, self.tr("Export to file"), self.tr("Export finished."))
		return QDialog.accept(self)


if __name__ == '__main__':
	import sys
	a = QApplication(sys.argv)
	dlg = DlgLoadData()
	dlg.show()
	sys.exit(a.exec_())