FixGeometry.py

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

"""
***************************************************************************
    FixGeometry.py
    -----------------------
    Date                 : January 2017
    Copyright            : (C) 2017 by Alexander Bruy
    Email                : alexander dot bruy at gmail dot com
***************************************************************************
*                                                                         *
*   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.                                   *
*                                                                         *
***************************************************************************
"""

__author__ = 'Alexander Bruy'
__date__ = 'January 2017'
__copyright__ = '(C) 2017, Alexander Bruy'

# This will get replaced with a git SHA1 when you do a git archive

__revision__ = '$Format:%H$'

from qgis.core import (QgsWkbTypes,
                       QgsGeometry,
                       QgsApplication,
                       QgsMessageLog,
                       QgsProcessingUtils)

from processing.core.GeoAlgorithm import GeoAlgorithm
from processing.core.parameters import ParameterVector
from processing.core.outputs import OutputVector
from processing.core.GeoAlgorithmExecutionException import GeoAlgorithmExecutionException
from processing.tools import dataobjects


class FixGeometry(GeoAlgorithm):

    INPUT = 'INPUT'
    OUTPUT = 'OUTPUT'

    def icon(self):
        return QgsApplication.getThemeIcon("/providerQgis.svg")

    def svgIconPath(self):
        return QgsApplication.iconPath("providerQgis.svg")

    def tags(self):
        return self.tr('repair,invalid,geometry').split(',')

    def group(self):
        return self.tr('Vector geometry tools')

    def name(self):
        return 'fixgeometries'

    def displayName(self):
        return self.tr('Fix geometries')

    def defineCharacteristics(self):
        self.addParameter(ParameterVector(self.INPUT,
                                          self.tr('Input Layer'),
                                          [dataobjects.TYPE_VECTOR_POLYGON, dataobjects.TYPE_VECTOR_LINE]))
        self.addOutput(OutputVector(self.OUTPUT,
                                    self.tr('Layer with fixed geometries')))

    def processAlgorithm(self, context, feedback):
        layer = QgsProcessingUtils.mapLayerFromString(self.getParameterValue(self.INPUT), context)

        writer = self.getOutputFromName(
            self.OUTPUT).getVectorWriter(layer.fields(), QgsWkbTypes.multiType(layer.wkbType()), layer.crs(), context)

        features = QgsProcessingUtils.getFeatures(layer, context)
        if QgsProcessingUtils.featureCount(layer, context) == 0:
            raise GeoAlgorithmExecutionException(self.tr('There are no features in the input layer'))

        total = 100.0 / QgsProcessingUtils.featureCount(layer, context)
        for current, inputFeature in enumerate(features):
            outputFeature = inputFeature
            if inputFeature.geometry():
                outputGeometry = inputFeature.geometry().makeValid()
                if not outputGeometry:
                    QgsMessageLog.logMessage('makeValid failed for feature {}'.format(inputFeature.id()), self.tr('Processing'), QgsMessageLog.WARNING)

                if outputGeometry.wkbType() == QgsWkbTypes.Unknown or QgsWkbTypes.flatType(outputGeometry.geometry().wkbType()) == QgsWkbTypes.GeometryCollection:
                    tmpGeometries = outputGeometry.asGeometryCollection()
                    for g in tmpGeometries:
                        if g.type() == inputFeature.geometry().type():
                            try:
                                g.convertToMultiType()
                                outputFeature.setGeometry(QgsGeometry(g))
                                writer.addFeature(outputFeature)
                            except:
                                pass
                    feedback.setProgress(int(current * total))
                    continue

                outputGeometry.convertToMultiType()
                outputFeature.setGeometry(outputGeometry)

            writer.addFeature(outputFeature)
            feedback.setProgress(int(current * total))

        del writer