[processing] Add algorithm to strip null geometries

qgis · Oct 21, 2016 · 3748497 · 3748497
1 parent 00653d2
commit 3748497
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Showing 3 changed files with 70 additions and 1 deletion.
diff --git a/python/plugins/processing/algs/help/qgis.yaml b/python/plugins/processing/algs/help/qgis.yaml
@@ -362,6 +362,8 @@ qgis:refactorfields: >
 
 qgis:regularpoints:
 
+qgis:removenullgeometries: >
+  This algorithms removes any features which do not have a geometry from a vector layer. All other features will be copied unchanged.
 
 qgis:reprojectlayer: >
   This algorithm reprojects a vector layer. It creates a new layer with the same features as the input one, but with geometries reprojected to a new CRS.

diff --git a/python/plugins/processing/algs/qgis/QGISAlgorithmProvider.py b/python/plugins/processing/algs/qgis/QGISAlgorithmProvider.py
@@ -150,6 +150,7 @@
 from .BoundingBox import BoundingBox
 from .Boundary import Boundary
 from .PointOnSurface import PointOnSurface
+from .RemoveNullGeometry import RemoveNullGeometry
 
 pluginPath = os.path.normpath(os.path.join(
     os.path.split(os.path.dirname(__file__))[0], os.pardir))
@@ -202,7 +203,8 @@ def __init__(self):
                         ReverseLineDirection(), SpatialIndex(), DefineProjection(),
                         RectanglesOvalsDiamondsVariable(),
                         RectanglesOvalsDiamondsFixed(), MergeLines(),
-                        BoundingBox(), Boundary(), PointOnSurface()
+                        BoundingBox(), Boundary(), PointOnSurface(),
+                        RemoveNullGeometry()
                         ]
 
         if hasMatplotlib:

diff --git a/python/plugins/processing/algs/qgis/RemoveNullGeometry.py b/python/plugins/processing/algs/qgis/RemoveNullGeometry.py
@@ -0,0 +1,65 @@
+# -*- coding: utf-8 -*-
+
+"""
+***************************************************************************
+    RemoveNullGeometry.py
+    --------------
+    Date                 : October 2016
+    Copyright            : (C) 2016 by Nyall Dawson
+    Email                : nyall dot dawson 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__ = 'Nyall Dawson'
+__date__ = 'October 2016'
+__copyright__ = '(C) 2016, Nyall Dawson'
+
+# This will get replaced with a git SHA1 when you do a git archive323
+
+__revision__ = '$Format:%H$'
+
+from processing.core.GeoAlgorithm import GeoAlgorithm
+from processing.core.parameters import ParameterVector
+from processing.core.outputs import OutputVector
+from processing.tools import dataobjects, vector
+
+
+class RemoveNullGeometry(GeoAlgorithm):
+
+    INPUT_LAYER = 'INPUT_LAYER'
+    OUTPUT_LAYER = 'OUTPUT_LAYER'
+
+    def defineCharacteristics(self):
+        self.name, self.i18n_name = self.trAlgorithm('Remove null geometries')
+        self.group, self.i18n_group = self.trAlgorithm('Vector selection tools')
+
+        self.addParameter(ParameterVector(self.INPUT_LAYER,
+                                          self.tr('Input layer'), [ParameterVector.VECTOR_TYPE_ANY]))
+        self.addOutput(OutputVector(self.OUTPUT_LAYER, self.tr('Removed null geometry')))
+
+    def processAlgorithm(self, progress):
+        layer = dataobjects.getObjectFromUri(
+            self.getParameterValue(self.INPUT_LAYER))
+        writer = self.getOutputFromName(
+            self.OUTPUT_LAYER).getVectorWriter(
+                layer.fields(),
+                layer.wkbType(),
+                layer.crs())
+
+        features = vector.features(layer)
+        total = 100.0 / len(features)
+
+        for current, input_feature in enumerate(features):
+            if input_feature.constGeometry():
+                writer.addFeature(input_feature)
+
+            progress.setPercentage(int(current * total))
+
+        del writer